Few studies have examined the mediators of behavior change in successful school-based physical activity interventions. The aim of this study was to explore potential mediators of physical activity in the Fit-4-Fun program for primary school children.Group randomized controlled trial.Four primary schools were recruited in April, 2011 and randomized by school into intervention or control conditions. Participants included 213 children  with the treatment group (n = 118) completing the 8-week multi-component Fit-4-Fun program. Participants were assessed at baseline, 3- and 6-months. Physical activity was measured using Yamax SW700 pedometers (mean steps/day) and questionnaires were used to assess constructs from Social Cognitive Theory and Competence Motivation Theory. Hypothesized mediators measured included social support from peers, parents and teachers; physical activity self-efficacy (barrier and task); enjoyment; and perceived school physical environment. Mediation was assessed using Preacher and Hayes’ multiple mediation regression SPSS macro. Action theory (A), conceptual theory (B) and the significance of the product of coefficients (AB) are reported.The intervention had a significant effect on physical activity (p<0.001). The action theory test results revealed significant treatment effects at 3-months for perceived school environment ; and at 6-month follow-up for perceived school environment , teacher social support  and enjoyment . The conceptual theory test revealed a significant relationship between changes in teacher social support and changes in physical activity at 6-month follow-up . Teacher social support was shown to have a significant mediating effect on physical activity , and perceived school environment approached significance .The Fit-4-Fun program successfully targeted social support for physical activity provided by classroom teachers which contributed to improved physical activity in children. These results demonstrate that classroom teachers play a key role in influencing physical activity behavior outcomes in children.ACTRN12611000976987Trial Registration No:  Physical activity is an important predictor of physical and psychological health in young people ,2, and pSchools have been universally identified as important institutions for the promotion of physical activity in children and youth , and quaAs such, there is growing demand for researchers to explore and report mediators of physical activity change in youth interventions ,17. MediA review of physical activity interventions that reported physical activity outcomes and potential mediators of behavioral change among children  identifiThe application of behavioral theory is imperative when designing interventions for children as the theoretical constructs can help researchers determine how the intervention worked and how future interventions can be improved ,22. The The study protocols of the Fit-4-Fun program and the intervention effects on fitness and behavioral outcomes have been reported elsewhere ,15. The The Fit-4-Fun program was evaluated using a group RCT with 226 Stage 3 (Grade 5 and 6) students from four primary schools  located in the Hunter Region, NSW, Australia. There were 10 teachers from the 4 schools (2 × treatment and 2 × control schools), with 5 classes in each study group (3 × year 6 and 3 × year 5 in each). Schools were randomized into the Fit-4-Fun treatment (n=118) or wait-list control conditions (n=108) following baseline assessments. The random allocation sequence was generated by a computer-based random number-producing algorithm and completed by a researcher not involved in the project to ensure an equal chance of allocation to each group. Assessments were conducted in April (baseline), June (3-month follow up) and December (6-month follow-up), 2011, and completed by trained research assistants who were blinded to treatment conditions at baseline assessments. The study was registered with the Australia and New Zealand Clinical Trials registry (ACTRN12611000976987). Ethics approval for this study was obtained from the University of Newcastle, NSW, Australia and the Newcastle-Maitland Catholic Schools Office, and school Principals, teachers, parents and study participants provided written informed consent. The methods of the Fit-4-Fun study have been reported in detail elsewhere , with thThe Fit-4-Fun intervention was informed by the Fit-4-Fun pilot study  and a dea) Fit-4-Fun InterventionTheoretical framework: The Fit-4-Fun Program was grounded in Bandura’s Social Cognitive Theory (SCT) and Harter’s Competence Motivation Theory (CMT) and aimed to provide children with the knowledge and skills necessary for short- and long-term PA behavior change ..74]. TheSocial support for physical activity from friends did not exhibit mediating effects on physical activity behaviors in this study. Research in this area is sparse, with many investigators evaluating the important role of peers as a moderator of social and emotional development , rather Contrary to recent data suggesting that both self-efficacy and enjoyment are positively associated with physical activity in children and youth ,17,20,32Furthermore, children are generally optimistic about their abilities, but these start to decline during adolescence. This was demonstrated in another physical activity intervention by Lubans et al. (2010), who also found that physical activity self-efficacy did not mediate changes in physical activity behavior in adolescents . HoweverThe school’s physical environment is also an area that has received much attention in promoting physical activity in the school setting ,74. The This study has noteworthy strengths that include: a novel intervention targeting physical activity and fitness in children, a high quality trial that adhered to the CONSORT statement , excelleAdditionally, mediation analysis using Preacher and Hayes’ Multiple Mediation Regression  uses comMediation analysis is an important component of physical activity research and is a useful tool in identifying the variables responsible for changes in physical activity . Our stuSCT: Social Cognitive Theory; CMT: Competence Motivation Theory; HRF: Health-Related Fitness; HR: Heart rate; CRF: Cardio-respiratory fitness; MF: Muscular fitness; PA: Physical activity; PF: Physical fitness.The authors declare that they have no competing interests.Study concept and design: NE, PJM, and DRL. Acquisition of data: NE. Analysis and interpretation of data: NE. Drafting of manuscript: NE. Critical revision of the manuscript: MPJ and DRL. Statistical analysis: NE and DRL. Obtained funding: NE, DRL, PJM. All authors read and approved the final manuscript.


Symptoms of malaria and pneumonia overlap in African under-five children and the integrated management of childhood illness strategy require that such children be managed presumptively with both antibiotics and antimalarials. A 2003 WHO expert meeting recommended the evaluation of malaria rapid diagnostic test in the management of children with this overlap, but this has not been evaluated. Therefore, the objective of this study was to compare the clinical outcome of presumptive versus malaria rapid diagnostic test-based management of childhood malaria-pneumonia overlap in Nigeria.A pilot quasi-experimental study was conducted November 2009 through February 2010 in an urban comprehensive health centre in Ogun, South-Western Nigeria. First, 50 children with malaria-pneumonia symptom overlap were consecutively enrolled and treated presumptively with antibiotics and antimalarials irrespective of malaria test result (control arm).Then, another 50 eligible children were enrolled and treated with antibiotics with/out antimalarials based on rapid diagnostic test result (intervention arm). Primary endpoint: clinical cure at day-5. The data were analyzed using Epi Info version 3.4.1.The intervention and control arms did not differ significantly regarding patient demographic and clinical characteristics. Clinical cure rate was slightly higher in children managed presumptively 49 (98%) than those managed rapid diagnostic test -based 47 (94%) (P = 0.31). However, rapid diagnostic test -based treated children had lower risk of receiving antimalarials compared to those treated presumptively (48% vs. 100%), . No death or severe complications were recorded in either group at day-5 follow-up.Outcome of rapid diagnostic test-based treatment is not inferior to presumptive management in children with malaria-pneumonia symptom overlap. More extensive studies with larger sample sizes are needed. The children .Although the accuracy of RDTs for malaria infection has been demonstrated , there iThis was a pilot quasi-experimental study conducted November 2009 through February 2010. First, November through December 2009, fifty children with malaria-pneumonia symptom overlap were consecutively enrolled and treated presumptively with antibiotics and antimalarials irrespective of malaria test results according to national/ WHO/UNICEF guidelines (control arm). Then, January through February 2010, another 50 eligible children were consecutively enrolled and treated with antibiotics with/out antimalarials based on rapid diagnostic test result (intervention arm). The primary endpoint was clinical cure at day-5. Secondary endpoints were frequency of clinic re-attendance; persistence of presenting problems at follow-up, and proportion of unnecessary antimalarial treatment.The study was performed in an urban comprehensive health centre in Abeokuta-south district, Ogun state, South-western Nigeria. The health centre is located in the rain forest belt of Nigeria, an area with perennial malaria transmission.Inclusion criteria were; age 2 – 59months, clinical (IMCI) malaria (defined as axillary temperature of ≥37.5°C or a history of fever within 48hours of presentation) with clinical (IMCI) pneumonia , living within 3 kilometers of the health centre, and provision of informed consent. Exclusion criteria were; severe clinical state requiring urgent attention; presence of co-morbidities like otitis media, persistent vomiting, diarrhea etc.Paracheck Pf . In the control arm, all the study children received oral antimalarial  and antibiotic (amoxicillin) irrespective of RDT result. And in the intervention arm, children with a positive RDT result received both antimalarial and antibiotics while those with a negative RDT result received antibiotic only. The artesunate - amodiaquine combination antimalarials used was a 3-day regimen pre-packaged for children 2–11 months or 12–59 months. The oral amoxicillin (antibiotics) used was prescribed at 50mg/kg/day in two divided doses for five days.The children were examined by a study clinician and their axillary temperature was measured. Capillary blood was obtained and malaria rapid diagnostic test was performed by a laboratory technician using All data were recorded in a standard IMCI forms and a follow-up was performed for all patients at day 5. Patients were instructed to return for assessment at any time if the symptoms deteriorated during or after the day-5 follow-up period. Patients who failed to visit the hospital were actively followed - up on day - 6.Data were double-entered and analyzed with Epi Info . Continuous variables were expressed as median (±standard deviation) and categorical variables summarized using percentiles. Group comparisons were made (where appropriate) using the Wilcoxon two-sample test and uncorrected chi-square test, and their corresponding P-values were used for statistical inference.Before data collection, the Research Committee - Primary Health Care and Disease Control department of Abeokuta-south local government area, Ogun state, Nigeria read and approved the study protocol. Verbal informed consent was obtained from parents/legal guardian of enrolled children.control and intervention arms did not differ significantly in their demographic and clinical characteristics  than in the intervention arm (3± 0.7 days) (P = <0.001). However, rapid diagnostic test -based treated children had lower risk of receiving antimalarials compared to those treated presumptively (48% vs. 100%), . Three children in the intervention arm versus one child in the control arm had persistence of symptoms during follow-up (P = 0.31). A repeat RDT for all of them was negative and they were all referred to a tertiary hospital  . HoweverAfter decades of presumptive treatment strategies, the restriction of antimalarials to parasitologically-confirmed cases is necessarily difficult . AlthougA major drawback of the RDT - based strategy in the management of fevers in low resource settings is healthcare providers' failure to adhere to not prescribing antimalarials to children with a negative test , 10, 12.Children managed based on RDT had a higher median fever clearance time, and re-attended clinic more during follow-up compared to those managed presumptively. This is not consistent with observations of the RDT strategy made in the context of fevers in children , 10. TheThis is a pilot study; therefore, the findings are at best preliminary and need to be interpreted with caution. The study suffers from small sample size and lack of randomization, and there may be error from confounding factors from care seeking practices, patient's socio-economic status and/or selection/observer bias. With these limitations, the findings support the rationale for the use of RDTs in the management of children with malaria-pneumonia overlap. A randomized controlled trial that has accommodated these limitations is required to confirm these findings.


Plasmodium falciparum gametocytes in humans, knowledge of which would be useful in the development of anti-gametocyte vaccines, which would have the capability to reduce malaria transmission from humans to mosquitoes. In a study in the Gambia, mature gametocyte-infected erythrocytes of P. falciparum were found to carry antigens  that were recognised by malaria patient’s plasma antibodies. These anti-GSA antibodies, taken at a single timepoint, were weakly associated with lower duration of gametocyte carriage in these treated patients [in vivo.Malaria transmission-reducing interventions are key components of malaria control and elimination . Howeverpatients ,3. We thP./falciparum-positive children attending school in a rainforest region in Ghana. These children were treated with dihydro-artemisinin piperaquine, and followed up weekly for 1 month.Flow cytometry of cultured gametocyte-infected erythrocytes from 3D7 and from two recently adapted gametocyte-producung lines was used to detect and measure plasma antibodies recognising the erythrocyte surface. Plasma was obtained from asymptomatic By microscopy, 8.9% (15/168) of the children enrolled carried gametocytes and a further 20% of them developed gametocytes during subsequent follow-up.  Preliminary results from 113 samples tested in flow cytometry show that more than 50% of those in the sub-group of children with gametocytes at enrolment carry antibodies to GSA, and we expect this proportion to increase as gametocytes are developed during the follow-up. Further longitudinal flow cytometry, and NASBA analyses will enable us to understand the dynamics between immune responses to gametocytes and gametocyte carriage following treatment of asymptomatic malaria.


In univariate analyses adjusted for gender, minutes spent in hypoglycemia were significantly correlated with age , waist circumference , 2-h glucose , and 2-h insulin . In a stepwise multivariate regression analysis, the variables significantly associated with IMT were minutes spent in hypoglycemia , and ISI index , accounting for 34.1% of the variation. Episodes of hypoglycemia may be considered as a new potential cardiovascular risk factor for IGT individuals.Hypoglycemia is associated with increased risk of cardiovascular adverse clinical outcomes. There is evidence that impaired glucose tolerance (IGT) is associated with cardiovascular morbidity and mortality. Whether IGT individuals have asymptomatic hypoglycemia under real-life conditions that are related to early atherosclerosis is unknown. To this aim, we measured episodes of hypoglycemia during continuous interstitial glucose monitoring (CGM) and evaluated their relationship with early manifestation of vascular atherosclerosis in glucose tolerant and intolerant individuals. An oral glucose tolerance test (OGTT) was performed in 79 non-diabetic subjects. Each individual underwent continuous glucose monitoring for 72 h. Cardiovascular risk factors and ultrasound measurement of carotid intima-media thickness (IMT) were evaluated. IGT individuals had a worse cardiovascular risk profile, including higher IMT, and spent significantly more time in hypoglycemia than glucose-tolerant individuals. IMT was significantly correlated with systolic ( Hypoglycemia is a well-known side effect of glucose-lowering therapy in both type 1 and type 2 diabetes mellitus, and becomes more prevalent with treatment intensification Seventy-nine non-diabetic Caucasian subjects were consecutively recruited at the Department of Internal Medicine of the University of Rome-Tor Vergata. Recruitment mechanisms include word-of-mouth, fliers, and newspaper advertisements. Subjects, aged 23–70 years, were excluded if they had history of cardiovascular disease, including peripheral atherosclerosis, chronic gastrointestinal diseases associated with malabsorption, chronic pancreatitis, history of any malignant disease, history of alcohol or drug abuse, liver or kidney failure, or received treatments able to modify glucose metabolism including glucose-lowering, lipid-lowering and antihypertensive therapy. None of the subjects were taking anti-platelet medications. All subjects underwent an anthropometrical evaluation and readings of clinic blood pressure were obtained in the left arm of the supine patients, after 5 min of quiet rest, with a mercury sphygmomanometer. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were recorded at the first appearance (phase I) and at the disappearance (phase V) of Korotkoff sounds. Blood pressure values were calculated as the average of the last two of three consecutive measurements obtained at 3-mins intervals. After 12-h fasting, a 75 g OGTT was performed with 0, 30, 60, 90 and 120 min sampling for plasma glucose and insulin. The Matsuda index of insulin sensitivity (ISI) was calculated as reported IMT of the common carotid artery was measured by ATL HDI 3000 ultrasound system  equipped with a 5 MHz linear array transducer as previously described The protocol was approved by the institutional ethical committee the University of Rome-Tor Vergata and informed written consent was obtained from each participant in accordance with principles of the Declaration of Helsinki.2 test. The coefficient of variation (CV) of interstitial glucose during CGM was calculated as the ratio of the standard deviation to the mean. Phenotypic differences between groups were tested after adjusting for age, and gender using a general linear model. Partial correlation coefficients adjusted for age and gender were computed between variables. Relationships between variables were sought by stepwise multivariate linear regression analysis to assess their independent contribution to IMT. A P value<0.05 was considered statistically significant. All analyses were performed using SPSS software Version 16.0.Continuous data are expressed as means ±SD. Categorical variables were compared by χr = 0.26; P = 0.01), waist circumference , 2-h post-load plasma glucose , and 2-h post-load insulin . In univariate analyses adjusted for gender and age, carotid IMT was significantly correlated with systolic and diastolic blood pressure, total and LDL cholesterol, 2-h post-load plasma glucose, insulin sensitivity, and minutes spent in hypoglycemia , and ISI index , accounting for 34.1% of the variation.The anthropometric and cardio-metabolic characteristics of the study groups are shown in glycemia . A stepwTo the best of our knowledge, this is the first study evaluating the association between episodes of hypoglycemia, assessed by CGM under real-life conditions, and preclinical atherosclerosis in non-diabetic subjects with different degrees of glucose tolerance. Our findings suggest that IGT individuals have asymptomatic episodes of hypoglycemia and spend more than 2 hrs per day below the hypoglycemia threshold of <70 mg/dl. The hypoglycemic episodes were significantly correlated with 2-h post-load plasma glucose and insulin levels, thus raising the possibility that hypoglycemia occurs during the late post-prandial period as a consequence of a prolonged release of insulin in response to elevated glucose levels.Performance assessment of the Medtronic-MiniMed CGM system has demonstrated that it has an acceptable clinical accuracy, with 96.6% of paired sensor-blood glucose self monitoring readings falling in the ‘clinically acceptable’ zones A and B of the Clarke error grid for type 1 diabetic subjects The measurement of IMT of the common carotid artery is a well accepted method to monitor the early stages of atherosclerosis and IMT increase precedes the development of plaque and stenosis in the arterial wall. Furthermore, IMT of the common carotid artery has been shown to be related to prevalent and incident cardiovascular disease Although observational studies have reported a strong association between hyperglycemia and increased risk for cardiovascular disease in individuals with type 2 diabetes, the results of recent interventional randomized controlled trials in establishing the benefit of intensive glycemic control on cardiovascular outcomes have been elusive This study has some strengths including the measurement of plasma glucose during an OGTT in drug-naïve individuals thus excluding the confounding effect of medications affecting glucose, and assessment of CGM under real-life conditions. Nonetheless, the present study has limitations. CGM has intrinsic limitations since it measures interstitial fluid rather than blood glucose levels. In addition, OGTTs were performed once, and, thus, intra-individual variation in plasma glucose levels cannot be taken into account leading to possible misclassification of some subjects with IGT. The cross-sectional design of the study does not provide insights into the time course of the development of cardiovascular disease, and, therefore, no conclusions regarding cause-effect relationships can be made. Finally, the present findings are only based on Caucasian individuals, and results might vary as a function of ethnic group.In conclusion, since hypoglycemic episodes are considered to be among the mediators of cardiovascular events, our findings indicate that exposure to glucose levels below the hypoglycemia threshold remains under-appreciated in individuals with IGT. The present results suggest that it is common for persons who are classified as ‘pre-diabetic” to experience transient hypoglycemia during everyday circumstances.


Statins are extensively used for cardiovascular disease prevention. Statins reduce mortality rates more than other lipid-modulating drugs, although evidence from randomized controlled trials also suggests that statins unexpectedly increase the risk of diabetes and improve immune function. Physiologically, statins would be expected to lower androgens because statins inhibit production of the substrate for the local synthesis of androgens and statins' pleiotropic effects are somewhat similar to the physiological effects of lowering testosterone, so we hypothesized that statins lower testosterone.a priori hypothesis that statins lower testosterone. We searched the PubMed, Medline and ISI Web of Science databases until the end of 2011, using '(Testosterone OR androgen) AND (CS-514 OR statin OR simvastatin OR atorvastatin OR fluvastatin OR lovastatin OR rosuvastatin OR pravastatin)' restricted to randomized controlled trials in English, supplemented by a bibliographic search. We included studies with durations of 2+ weeks reporting changes in testosterone. Two reviewers independently searched, selected and assessed study quality. Two statisticians independently abstracted and analyzed data, using random or fixed effects models, as appropriate, with inverse variance weighting.A meta-analysis of placebo-controlled randomized trials of statins to test the Of the 29 studies identified 11 were eligible. In 5 homogenous trials of 501 men, mainly middle aged with hypercholesterolemia, statins lowered testosterone by -0.66 nmol/l  -0.14 to -1.18). In 6 heterogeneous trials of 368 young women with polycystic ovary syndrome, statins lowered testosterone by -0.40 nmol/l (95% CI -0.05 to -0.75). Overall statins lowered testosterone by -0.44 nmol/l (95% CI -0.75 to -0.13).Statins may partially operate by lowering testosterone. Whether this is a detrimental side effect or mode of action warrants investigation given the potential implications for drug development and prevention of non-communicable chronic diseases.http://www.biomedcentral.com/1741-7015/11/58See commentary article here  Statins are extensively used in the West for secondary prevention of cardiovascular diseases, and have contributed to a reduction in cardiovascular disease mortality rates. Statin use will become more common globally with the emerging epidemic of cardiovascular disease in developing countries and the increasing availability of statins off patent. Randomized controlled trials (RCTs) show statins reduce mortality rates more than other commonly used lipid-modulating therapies ,2, such de novo synthesis of cholesterol throughout the body [de novo cholesterol in the gonads [a priori that the pleiotropic effects of statins could be due to lowering of androgens, that is, that statins lower androgens and that lower androgens might mediate the pleiotropic effects of statins. Here, we carried out a meta-analysis of placebo-controlled randomized trials, to avoid bias by indication, in men and women to examine whether statins reduced total testosterone.Statins inhibit the enzyme 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase, which reduces cholesterol production. In contrast niacin blocks the breakdown of fats, fibrates activate peroxisome proliferator-activated receptor (PPAR)-α and ezetimibe inhibits cholesterol absorption. All modulate circulating lipids, but only statins also inhibit the body . Concernthe body  either be gonads  and elsee gonads , but thie gonads -16. Lowee gonads , whilst e gonads . Men wite gonads . Extensie gonads ,21 and ie gonads ,23. GiveWe implemented this meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist  AND (CS-514 OR statin OR simvastatin OR atorvastatin OR fluvastatin OR lovastatin OR rosuvastatin OR pravastatin)' with the search limited to RCTs of studies in humans in English, because an initial search suggested the relevant literature was in English. From our search, we discarded any studies that were not relevant from the title or abstract and read the remaining to identify placebo-controlled randomized trials of statins with testosterone reported. We also used the references of the selected trials to identify additional relevant trials.We included any published placebo-controlled randomized trial in English of at least 2 weeks' duration examining the effect of statins on testosterone in adults, because statins act rapidly on cholesterol . We did A statistician (GF) extracted information by trial arm on number of participants, testosterone assays used, and mean and standard deviation of the change in testosterone during the trial. Where this information was not provided in full, the statistician (GF) made conservative estimates based on the information available. A second statistician (BJC) then checked the information extracted and any estimates. The reviewers (CMS and SLAY) independently used an established tool to evaluate the quality of each trial , and a s2 to assess heterogeneity between trials. To obtain an estimate of the difference in mean testosterone between statin and placebo groups, we combined the results of the selected trials using inverse variance weighting and a fixed or random effects model depending on the level of heterogeneity, using the 'metacont' function from the 'meta' package of R 2.14.1 . We considered men and women together and separately because of the different hormone milieu by sex. We did no other subgroup analysis.We used funnel plots to assess publication bias, and IThis study is an analysis of published data, which does not require ethics committee approval.The initial searches yielded 27 studies. Two additional trials ,25 were Table Funnel plots gave little indication of publication bias among men Figure , but amo2 = 0%), with the overall estimate within the confidence intervals of all trials. Statins lowered testosterone by about 3.4% among men  -0.14 to -1.18) in both fixed and random effects models, and the estimate was similar  including only the higher quality trials [2 = 90.1%). Statins lowered testosterone by about 12.3% among women  in a random effects model, with similar results when the most extreme study [2 = 79%). Statins lowered testosterone overall  in a random effects model; results were similar when each of the three most influential trials was removed, or when only considering the higher quality trials  [Figure y trials ,16,29. Fme study  was omitme study -33. For o -1.02) ,16,29-33This meta-analysis of placebo-controlled randomized trials suggests statins reduce testosterone. Among men the evidence was homogeneous and largely related to typical doses for the target group using statins for the prevention of cardiovascular disease, where statins potentially lowering testosterone has always been a concern ,12,14-16To the best of our knowledge no previous meta-analysis of placebo-controlled randomized trials has assessed the effect of statins on testosterone among men. Two trials comparing simvastatin 80 mg/day with 40 mg/day among in total 640 men found median testosterone lower by 10.3% and 7.5% respectively after 48 weeks , consistThe clinical significance of this reduction in testosterone with statins is difficult to gauge. The normal range of testosterone is wide  and sexuDespite providing a meta-analysis of all known placebo-controlled randomized trials, limitations exist. First, given when they were conducted, not all the trials had high quality scores. However, they had the expected effects on lipids. Second, not all the trials were intended to assess the effects of statins on testosterone. However, the trial, largely designed for this purpose , is inflThis meta-analysis shows that statins reduce testosterone. This finding does not demonstrate that androgens mediate any health effect of statins, but raises the question as to whether testosterone modulation plays a role in statins' effects on health, particularly among men where testosterone is an important hormone. Whether reducing testosterone enhances or impairs the protective effects of statins on cardiovascular mortality needs to be determined urgently, because it could enable the development of enhanced statin based treatments, the development of other drugs in the same class and the identification of potentially modifiable population-wide risk factors for several non-communicable chronic diseases.HMG-CoA: 3-hydroxy-3-methyl-glutaryl-CoA reductase; PPAR: peroxisome proliferator-activated receptor; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses; RCT: randomized controlled trial.BJC has received research funding from MedImmune Inc., and consults for Crucell MV. The authors report no other potential conflicts of interest.CMS originated the idea for the paper. CMS and SLAY carried out the systematic search. GF and BJC did the data extraction and analysis. CMS drafted the paper with assistance from SLAY, GF and BJC. All authors reviewed the paper critically and have read and approved the manuscript for publication. All authors had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. CMS is the guarantor. All authors have read and approved the final manuscript.The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1741-7015/11/57/prepubCompleted Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist for this study. Information as to how this review was conducted.Click here for fileStudies excluded after scrutiny with reason for exclusion. A list, with references, of all the studies excluded from this meta-analysis.Click here for fileQuality assessment of the selected placebo controlled randomized controlled trials of the effects of statins on testosterone [osterone . QualityClick here for file


P = 0.002). We cross-validated the MRI-PDFF-determined fat content with that assessed by colocalized MRS; the latter showed a mean difference of 4.9% (P = 0.014) in liver fat between the colesevelam and the placebo arms. MRI-PDFF correlated strongly with MRS-determined hepatic fat content . Liver biopsy assessment of steatosis, cellular injury, and lobular inflammation did not detect any effect of treatment. Conclusion: Colesevelam increases liver fat in patients with NASH as assessed by MRI as well as MRS without significant changes seen on histology. Thus, MRI and MRS may be better than histology to detect longitudinal changes in hepatic fat in NASH. Underlying mechanisms and whether the small MR-detected increase in liver fat has clinical consequences is not known. Bile acid sequestrants (BAS) lower plasma low density lipoprotein levels and improve glycemic control. Colestimide, a BAS, has been claimed by computed tomography to reduce liver fat. Therefore, we examined the efficacy of colesevelam, a potent BAS, to decrease liver fat in patients with biopsy-proven nonalcoholic steatohepatitis (NASH). Liver fat was measured by a novel magnetic resonance imaging (MRI) technique, the proton-density-fat-fraction (PDFF), as well as by conventional MR spectroscopy (MRS). Fifty patients with biopsy-proven NASH were randomly assigned to either colesevelam 3.75 g/day orally or placebo for 24 weeks. The primary outcome was change in liver fat as measured by MRI-PDFF in colocalized regions of interest within each of the nine liver segments. Compared with placebo, colesevelam increased liver fat by MRI-PDFF in all nine segments of the liver with a mean difference of 5.6% ( Nonalcoholic steatohepatitis (NASH) is a severe form of nonalcoholic fatty liver disease (NAFLD) that is characterized by features of steatosis, hepatocellular injury, and parenchymal inflammation with or without perisinusoidal fibrosis on liver histology in individuals who consume little or no alcohol.Colesevelam, a bile acid sequestrant (BAS), interrupts the enterohepatic circulation of bile acids and causes increased conversion of hepatic cholesterol to bile acids. Colesevelam increases plasma glucagon-like-peptide-1 (GLP-1) levels, which activates pancreatic β-cells to release insulin. One possible mechanism by which colesevelam causes increased GLP-1 is by moving the site of fat absorption to the ileum where fat absorption by L cells causes GLP-1 release.71 bias and correcting T2* decay. This technique models the fat signal as a superposition of multiple frequency component interference to give a quantitative, standardized, and objective MRI measurement of hepatic fat content. Using MR spectroscopy (MRS) as a reference standard, PDFF has been shown to be an accurate, precise, and reproducible noninvasive method to assess hepatic steatosis.CT scanning is limited in its ability to accurately quantify liver fat. However, magnetic resonance imaging (MRI) provides a better assessment and accurate quantification of liver fat content. Recently, newer MRI has emerged as a useful modality that may be more accurate for the assessment of liver fat as compared to ultrasound, CT, and conventional MRI.This was an investigator-initiated, randomized, double-blind, allocation-concealed, placebo-controlled clinical trial. This study was designed and conducted according to the CONSORT Guidelines to evaluate the efficacy of 3.75 g colesevelam taken orally daily versus identical-appearing placebo for 24 weeks in reducing liver fat in patients with NASH. The CONSORT checklist is available as Supporting Patients were screened with history, physical examination, and all underwent an alcohol history assessment by completing the AUDIT and Skinner Lifetime Drinking questionnaire. Patients were asked to stop any medications being used for their liver disease including vitamins and herbal medications.3 or prothrombin time >16 seconds), or inability to undergo MRI.Inclusion criteria included age 18 years or older, having serum alanine (ALT) or aspartate (AST) aminotransferase activity above the upper limits of normal: 19 U/L or more for women and 30 U/L or more for men, and presence of hepatic steatosis of >5% by MRI-PDFF. All patients had liver biopsies with evidence of NASH on biopsy performed within 6 months of enrollment without any significant change in body weight and interventions for treatment of NASH between the date of liver biopsy and enrollment. All patients with definite NASH as defined by the presence of all of the following features including steatosis, ballooning degeneration, and lobular inflammation with or without fibrosis as well as those with features suspicious for NASH defined as an NAFLD activity score (NAS) of 4 or higher were eligible. NAS ranges from 0-8 and is a sum of steatosis score (0-3), lobular inflammation score (0-3), and ballooning degeneration score (0-2). Exclusion criteria: Subjects were excluded if they had evidence of other forms of liver disease shown by the presence of serum hepatitis B surface antigen (HBsAg), hepatitis C viral RNA (HCV RNA), positive autoimmune serologies, evidence for hemochromatosis by 3+ or 4+ stainable iron on biopsy or homozygosity on genetic analysis, low ceruloplasmin levels with biopsy suggestive of Wilson's disease or low alpha-1-antitrypsin levels with biopsy suggestive of alpha-1-antitrypsin disease. Exclusion criteria also included alcohol intake of more than 30 g per day in the previous 10 years or greater than 10 g per day in the previous year, decompensated liver disease with Child-Pugh score greater than 7 points, active substance abuse, significant systemic illnesses, renal insufficiency , positive human immunodeficiency virus (HIV) test, pregnancy, evidence of hepatocellular carcinoma , ingestion of drugs known to cause hepatic steatosis, contraindications to liver biopsy . Subjects underwent blood tests that included: ALT, AST, alkaline phosphatase, gamma-glutamyl transferase (GGT), total bilirubin, albumin, hemoglobin A1c, fasting glucose and insulin, prothrombin time/INR, lipid panel, and C-reactive protein (CRP).Liver biopsy performed within 6 months of the start of the study were used as baseline liver biopsy; otherwise, a percutaneous liver biopsy was performed and was scored using the Nonalcoholic Steatohepatitis-Clinical Research Network (NASH-CRN) histologic scoring system. A single hepatopathologist (M.P.), who was blinded to clinical as well as radiologic data, the order of liver biopsy specimens, and previous results of the biopsy, performed all liver biopsy assessment for this study. All biopsies were re-read after completion of the protocol. Blinding was not broken until after completion of all histologic as well as radiologic/clinical data collection procedures. The average  length of liver biopsy specimen was 16.9 mm (±3.3) and the average (±SD) number of portal tracts seen on the biopsy specimen were 10.6 (±2.7). These are similar to previously performed high-quality clinical trials in NASH and reflect good clinical practice at a large NAFLD clinical research site.NAS, which is the sum of the degree of steatosis (0-3), lobular inflammation (0-3), and hepatocellular ballooning (0-2), was obtained in all patients. The NAS ranges from 0-8. A two-point drop in NAS score was considered improvement in liver histology (with no change in hepatic fibrosis) and was considered an exploratory endpoint. Liver fibrosis (stage 0-4) was scored using the NASH-CRN histologic staging system (16).Subjects were randomized by the investigational drug services (IDS) at UCSD using computer-generated numbers to either treatment or placebo groups in blocks of 4 in a 1:1 ratio. Independent IDS pharmacists dispensed either active or placebo treatment pills, which were identical in appearance. Pills were prepackaged in identical bottles, labeled according to the computer-generated randomization numbers, and delivered to the research clinic office by a courier. The allocation sequence was concealed from the research coordinators and all investigators including hepatologists, radiologists, and pathologist who assessed and enrolled subjects in the trial. Patients were scheduled for individual appointments in the research clinic to avoid any overlapping appointments to reduce the likelihood of patients interacting and discussing treatment efficacy or side effects while in the waiting room. Treatment allocation was unblinded only after the completion of entire study procedures including all posttreatment liver biopsy and MRI studies on all patients.Upon meeting inclusion and exclusion criteria and completing baseline evaluation, patients were randomized at time designated as week 0 to receive either colesevelam 3.75 g/day  or placebo for a total of 24 weeks. Patients returned to the research clinic at weeks 4, 12, and 24 after randomization. At these clinic visits, routine blood tests were obtained, body weight and vital signs were recorded, and the number of pills was counted to document compliance. A physical exam and careful history of liver-related symptoms as well as possible side effects of colesevelam were also obtained at each visit. At the completion of 24 weeks of therapy with either colesevelam or placebo, patients underwent MRI and MRS, biochemical testing, and a liver biopsy. After stopping treatment, the subjects had an 8-week follow-up visit to monitor for possible late side effects of treatment.3 cube [voxel] within the liver).MRI was selected to measure the primary outcome because it is noninvasive, uses no ionizing radiation, provides objective and quantitative estimates of fat content throughout the entire liver, is more objective than ultrasound , is more accurate than CT , is more practical to perform and provides greater spatial coverage than MR spectroscopy  to minimize Tr-correlation coefficient between repeated measurements was greater than 0.99 with a percent-error of less than 1%.10The MRI-PDFF technique and the analysis software have been tested and refined in adult research subjects.2 in area placed on the PDFF parametric maps, avoiding blood vessels, bile ducts, and artifacts. To assess longitudinal changes in fat content, three colocalized ROIs were placed in each of the nine liver segments (27 separate ROIs) on the baseline and follow-up MR exams. For each segment, the three PDFF measurements were averaged.MR examinations were performed by experienced research MR technologists with expertise in the utilized procedures and analyzed, under the supervision of the radiology investigator (C.S.), by a single trained image analyst blinded to clinical data, treatment group allocation, histological data, and the order (baseline or follow-up) of each scan. Imaging PDFF was recorded in regions of interest (ROIs) ≈300 to 400 mmIn this study, MRS in a single location (voxel) in each liver was performed as a reference standard for colocalized MRI-PDFF measurements. In order to validate the accuracy of the imaging PDFF estimates, three additional ROIs were placed on the PDFF maps in the same locations as the spectroscopic voxel , and these PDFF measurements were averaged . MR spec2) test was used for comparisons between categorical variables and paired t test was used to compare mean differences between continuous variables in the colesevelam versus placebo groups. The primary analysis was performed as an intention-to-treat analysis. Primary and secondary comparisons within treatment groups were calculated using paired t tests, two-tailed independent sampled t tests, or nonparametric tests as appropriate. Pooled within group Pearson's correlations were used to look at associations across groups. A two-tailed P ≤ 0.05 was considered statistically significant. Statistical analyses were performed using SPSS v. 19.The chi-square  in the colesevelam-treated patients. There was a trend toward a decrease in fat fraction in the placebo group from 17.9% to 15.2%. Compared with placebo, colesevelam increased liver fat using MRI-PDFF with a mean difference of 5.6%, which was statistically significant (P = 0.002). Individual patient data on changes in liver fat by MRI-PDFF stratified by the treatment group is shown in The colesevelam group had an unexpected increase in MRI fat fraction in all nine liver segments, as shown in P = 0.014), as shown in r2 = 0.96 to 0.98 (P < 0.0001).To test the internal validity of MRI-PDFF findings, MRS (gold standard for hepatic fat quantification) was performed in colocalized ROIs with MRI-PDFF. MRS confirmed the results obtained by MRI-PDFF, with an increase in fat fraction in the colesevelam group and a decrease in the placebo group, with a mean difference of 4.9% (P = 0.001) and the difference was significant compared to placebo (P = 0.026) (P = 0.084), alkaline phosphatase , and GGT . Otherwise, there were no significant differences between the groups in AST, insulin, glucose, hemoglobin A1C, HOMA-IR, triglycerides, total cholesterol, HDL, free fatty acids, bilirubin, albumin, and prothrombin time over a 24-week period in this patient population.As expected, patients treated with colesevelam had a significant reduction in LDL cholesterol by 18% (= 0.026) . As coleP = 0.1). The mean change in NAS did not differ between in the two treatment arms. Within-group comparisons showed that the small subgroup of colesevelam patients with paired liver biopsy had a mild improvement in the steatosis but this was not significant when compared to placebo. There were no significant differences in liver histology between the two treatment arms. The results remained consistent when MRI-PDFF and MRS were examined within this subgroup of 31 patients showing a small amount of increase in liver fat in the colesevelam group and decrease in the placebo group (data not shown).Liver biopsy assessment did not detect any differences in steatosis grade between the two treatment arms . Of the Of the 25 patients in each treatment arm, two patients in the colesevelam group and three in the placebo dropped out of the study. In the colesevelam group, one patient discontinued treatment after 1 day of starting when baseline lipids revealed high triglycerides of 817 mg/dL and a second patient had medication discontinued when she developed diffuse muscle ache, which was not thought to be related to the study medication. In the placebo group, treatment was discontinued because one patient had exacerbation of his underlying inflammatory bowel disease shortly before week 12 of treatment; one had complaints of intolerable hot flashes, and one was lost to follow-up after moving out of the country because of employment. Overall, there were no differences in the side effects between the groups, as shown in the Supporting In this randomized, placebo-controlled, clinical trial, treatment with colesevelam compared to placebo was associated with an unexpected increase in liver fat in patients with NASH as assessed by a novel and accurate MRI technique. The internal validity of the MRI-derived changes in liver fat were confirmed by colocalized MR spectroscopy-based measurements. The increase in liver fat could only be detected by MRI and spectroscopy but not by liver biopsy. This discrepancy is presumably because histology was not available on all the 50 patients but only 31 patients who underwent paired liver biopsy, with 17 patients in the colesevelam arm and 14 patients in the placebo arm. In addition, it likely is influenced by type 1 error due to multiple comparisons in the histology tables. Furthermore, the validity of the liver biopsy to detect changes in steatosis is limited due to sampling variability and subjective assessment on an ordinal rather than a linear (or continuous) scale. Liver biopsy lacks the precision to ascertain small (3%) but real differences in liver fat content that can be appreciated by MRI and spectroscopy. The patient population had very minimal fibrosis and overall low NAS at baseline, which may have potentially influenced the study results. Utilizing a randomized controlled study design, we demonstrate that MRI-based PDFF may be a better tool than liver histologic assessment to assess longitudinal changes in hepatic steatosis in the setting of a clinical trial. This MRI-PDFF technique can be performed on routine clinical MRI scanners.To our knowledge, this is the first randomized, double-blinded, placebo-controlled trial to evaluate the use of colesevelam in the treatment of NASH, and the second to study BAS in this patient population. The earlier open-label study by Taniai et al.Although the results are contrary to our hypothesis and are opposite to the study done of Taniai et al., recent studies offer new insights to explain the effect of BAS on liver fat content and support the findings presented in this article. Brufau et al.We acknowledge the following limitations of our study. First, the results are contrary to the hypothesis and prior study by Taniai et al., which may suggest that there was insufficient compliance or power. However, the compliance was documented by pill count and was 95% in both groups. We also confirmed the LDL cholesterol-lowering effect of colesevelam compared to placebo as shown in previously published studies.The strengths of the trial include the randomized, placebo-controlled, double-blind design of the study. Allocation concealment and randomization technique and procedures have been described. Blinding was strictly enforced. Our study population was multiethnic, including a good proportion of non-Caucasians and had adequate sex-distribution, including 54% women.In this study we utilized a novel MRI-derived PDFF technique to perform fat mapping of the entire liver with detailed assessment of liver fat content in all nine segments of the liver before and after treatment. Further comparisons showed high correlation between MRI-derived PDFF and MRS-derived fat content. Segmental MRI-PDFF is a novel method that allows accurate quantification and localization of liver fat that is not feasible with current liver biopsy assessment. These data could also be utilized for determining sample size and estimating effect size in improving liver fat in weight loss studies in NASH/NAFLD.In conclusion, this randomized, placebo-controlled, clinical trial showed that colesevelam may cause a small but measurable increase in liver fat in patients with NASH. This change in liver fat could only be detected by MRI. This observation indicates that MRI-PDFF may be a better tool than liver histologic assessment to quantify changes in hepatic steatosis in the setting of a clinical trial. The MRI-based technique used to measure PDFF is widely available and can be applied on any MR platform. Future NASH studies may utilize these novel MRI-based whole liver fat mapping techniques to better quantify longitudinal changes in liver fat.


Increased arterial stiffness is associated with left ventricular diastolic dysfunction (LVDD), but this association may be influenced by left ventricular (LV) performance. Left ventricular hypertrophy (LVH) is not only a significant determinant of LV performance, but is also correlated with LVDD. This study is designed to compare LV diastolic function among patients divided by brachial-ankle pulse wave velocity (baPWV) and electrocardiography (ECG)-determined LVH and to assess whether increased baPWV and ECG-determined LVH are independently associated with LVDD.This cross-sectional study enrolled 270 patients and classified them into four groups according to the median value of baPWV and with/without ECG-determined LVH. The baPWV was measured using an ABI-form device. ECG-determined LVH was defined by Sokolow-Lyon criterion. LVDD was defined as impaired relaxation, pseudonormal, and restrictive mitral inflow patterns. Groups 1, 2, 3, and 4 were patients with lower baPWV and without ECG-determined LVH, lower baPWV but with ECG-determined LVH, higher baPWV but without ECG-determined LVH, and higher baPWV and with ECG-determined LVH respectively.Early diastolic mitral velocity (Ea) was gradually decreased from group 1 to group 4 (p≦0.027). Patients in group 4 had the highest prevalence of LVDD . After multivariate analysis, both baPWV and ECG-determined LVH were independent determinants of Ea  and LVDD .Our study showed the group with higher baPWV and ECG-determined LVH had the lowest Ea and highest prevalence of LVDD. In addition, both baPWV and ECG-determined LVH were independently associated with Ea and LVDD. Hence, assessment of arterial stiffness by baPWV and LVH by ECG may be useful in identifying the high risk group of LVDD. Increased pulse wave velocity (PWV), which reflects increased arterial stiffness, may result in left ventricular (LV) remodeling and thereby cause left ventricular diastolic dysfunction (LVDD) A clinical device, ABI-form , has been developed to automatically and simultaneously measure blood pressure (BP) in both arms and ankles and record pulse waves of the brachial and posterior tibial arteries using an automated oscillometric method. Using this device, we can easily obtain baPWV values This was a cross-sectional study. Study subjects were randomly included from a group of patients who arranged for echocardiographic examinations at Kaohsiung Municipal Hsiao-Kang Hospital. Patients with significant aortic or mitral valve disease, atrial fibrillation, or inadequate image visualization were excluded. We did not consecutively include all the patients because 12-lead ECG and baPWV measurement must be performed within 10 minutes after the completion of echocardiographic examination. Finally, 270 consecutive patients who agreed to have immediate ECG and baPWV were included in this study. The study population was further classified into 4 groups on the basis of the median value of baPWV and with/without ECG-determined LVH. Groups 1, 2, 3, and 4 were made up of patients with lower baPWV and without ECG-determined LVH, with lower baPWV but with ECG-determined LVH, with higher baPWV but without ECG-determined LVH, and with higher baPWV and with ECG-determined LVH respectively. All patients were in sinus rhythm.The study protocol was approved by the Institutional Review Board of the Kaohsiung Medical University Hospital (KMUH-IRB-20120132). Informed consents were obtained in written form from patients and all clinical investigations were conducted according to the principles expressed in the Declaration of Helsinki. The patients gave consent for the publication of the clinical details.Demographic and medical data including age, gender, history of diabetes mellitus, hypertension, and coronary artery disease, body mass index (BMI), systolic BP, diastolic BP, pulse pressure, and heart rate were obtained from medical records or interviews with patients. BMI was calculated as the ratio of weight in kilograms divided by the square of height in meters. Laboratory data including fasting glucose, triglyceride, total cholesterol, and hematocrit were also collected. In addition, information regarding patient medications including angiotensin converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), β-blockers, calcium channel blockers (CCBs), diuretics, and nitrates during the study period was obtained from medical records.2 in men and more than 95 g/m2 in women. The raw ultrasound data were recorded and analyzed offline, using software , by a cardiologist who was blinded to the other data.The echocardiographic examinations were performed by one experienced sonographer using transthoracic echocardiography , with the participant respirating quietly in the left decubitus position. Two-dimensional and two-dimensionally guided M-mode images were recorded from the standardized views. The Doppler sample volume was placed at the tips of the mitral leaflets to obtain the LV inflow waveforms from the apical 4-chamber view. All sample volumes were positioned with ultrasonic beam alignment to flow. Pulsed tissue Doppler imaging was obtained with the sample volume placed at the lateral corner of the mitral annulus from the apical 4-chamber view. The wall filter settings were adjusted to exclude high-frequency signals and the gain was minimized. A normal mitral inflow pattern was recognized if the ratio of transmitral E wave velocity (E) to transmitral A wave velocity (A) was ≧ 0.75, early diastolic mitral velocity (Ea) ≧ 8 cm/s, and E/Ea≤10, impaired relaxation mitral inflow pattern if the E/A ratio was <0.75, and pseudonormal/restrictive mitral inflow pattern if the E/A ratio was ≧ 0.75, Ea <8 cm/s or E/Ea >10 Within 10 minutes after the completion of the echocardiographic examination, baPWV was assessed using an ABI-form device, which automatically and simultaneously measures BP in both arms and ankles using an oscillometric method A standard 12-lead ECG was recorded during quiet respiration, with subjects in a supine position. The ECG was recorded at 25 mm/s and 0.1 mV/mm standardization. The Sokolow-Lyon voltage criterion was used for diagnosis of ECG-determined LVH. It is defined as (SV1+ RV5 or RV6) ≧ 35 mm t-test respectively. The relationship between two continuous variables was assessed by a bivariate correlation method (Pearson’s correlation). Subsequently, significantly correlated variables in the univariate analysis were further analyzed by multiple linear and logistic regression analyses to identify the factors associated with Ea and LVDD respectively. All tests were 2-sided and the level of significance was established as p<0.05.All data were expressed as means (± standard deviation). SPSS 18.0 software  was used for statistical analysis. Multiple comparisons between study groups were performed by one-way analysis of variance (ANOVA) followed by a post hoc test adjusted with a Bonferroni correction. Categorical and continuous variables between groups were compared by Chi-square analysis and independent-samples The comparison of clinical characteristics and arterial stiffness among the study groups is shown in The comparison of echocardiographic characteristics among the study groups is shown in The positive and negative predictive values, sensitivity, specificity, and accuracy of ECG-determined LVH in prediction of echocardiographic LVH were 67.6%, 61.3%, 38.4%, 84.1%, and 63.0% respectively. In addition, both ECG-determined LVH and echocardiographic LVH were significantly correlated with Ea and LVDD .There were three major findings in this study. First, Ea was gradually decreased from group 1 to group 4. Second, the group with higher baPWV and ECG-determined LVH by Sokolow-Lyon criterion had the highest prevalence of LVDD among the four study groups. Third, both baPWV and ECG-determined LVH by Sokolow-Lyon criterion were independently associated with Ea and LVDD.It is important to clarify the characteristics of the four groups in our study. Compared with patients in group 3, patients in group 2 were younger and composed of fewer patients of hypertension, but LV systolic function was more decreased. The characteristics of these four groups could generally be defined as follows: patients in group 1 had relatively normal cardiovascular function, patients in group 2 had relative systolic dysfunction, patients in group 3 had relative vascular dysfunction, and patients in group 4 had relative cardiovascular dysfunction. Cardiovascular dysfunction progresses with arterial–cardiac interactions, but the progression of dysfunction differs in speed between the heart and the vessels. In some patients, cardiac dysfunction progresses first (group 2), in another patients, vascular dysfunction progresses predominantly (group 3), but in other patients, cardiovascular dysfunction may concurrently occur (group 4). In patients with combined heart and vascular disease, the baPWV may be high due to atherosclerotic vessels, but in patients with relatively pure heart disease such as idiopathic-dilated cardiomyopathy, the baPWV may be low because of reducing LV ejection velocity. Although patients in group 2 with relative systolic dysfunction had a low baPWV, they had a comparable prevalence of pseudonormal/restrictive mitral inflow pattern with patients in groups 3 and 4. Furthermore, when compared to patients in group 3, patients in group 4 had a higher prevalence of LVDD. Therefore, the presence or absence of ECG-determined LVH may be an important and useful data when interpreting the relationship between baPWV and LV diastolic function.Increased PWV is an independent predictor of cardiovascular morbidity and mortality in the general population, hypertensive patients, the elderly, and patients with end-stage renal disease Aging has been reported to be associated with increased mean LV wall thickness, chamber diameter, mass, concentric remodeling, and a decline in LV diastolic function About half of the patients with heart failure have preserved LV systolic function. Although heart failure with preserved ejection fraction may be uneasily recognized, it is associated with marked increases in morbidity and all-cause mortality There are several limitations of this study. First, several criteria can be used to diagnose LVH via ECG In conclusion, the present study demonstrated that Ea was gradually decreased from group 1 to group 4 and the group with higher baPWV and ECG-determined LVH by Sokolow-Lyon criterion had the highest prevalence of LVDD among the four study groups. In addition, both baPWV and ECG-determined LVH as measured by the Sokolow-Lyon criterion were independently associated with Ea and LVDD. Hence, assessment of arterial stiffness by baPWV and LVH by ECG may be useful in identifying high-risk patients for LVDD.


IDE gene (IDE-KO mice).Insulin-degrading enzyme (IDE) is widely recognized as the principal protease responsible for the clearance and inactivation of insulin, but its role in glycemic control in vivo is poorly understood. We present here the first longitudinal characterization, to our knowledge, of glucose regulation in mice with pancellular deletion of the IDE-KO mice and wild-type (WT) littermates were characterized at 2, 4, and 6 months of age in terms of body weight, basal glucose and insulin levels, and insulin and glucose tolerance. Consistent with a functional role for IDE in insulin clearance, fasting serum insulin levels in IDE-KO mice were found to be ∼3-fold higher than those in wild-type (WT) controls at all ages examined. In agreement with previous observations, 6-mo-old IDE-KO mice exhibited a severe diabetic phenotype characterized by increased body weight and pronounced glucose and insulin intolerance. In marked contrast, 2-mo-old IDE-KO mice exhibited multiple signs of improved glycemic control, including lower fasting glucose levels, lower body mass, and modestly enhanced insulin and glucose tolerance relative to WT controls. Biochemically, the emergence of the diabetic phenotype in IDE-KO mice correlated with age-dependent reductions in insulin receptor (IR) levels in muscle, adipose, and liver tissue. Primary adipocytes harvested from 6-mo-old IDE-KO mice also showed functional impairments in insulin-stimulated glucose uptake.Our results indicate that the diabetic phenotype in IDE-KO mice is not a primary consequence of IDE deficiency, but is instead an emergent compensatory response to chronic hyperinsulinemia resulting from complete deletion of IDE in all tissues throughout life. Significantly, our findings provide new evidence to support the idea that partial and/or transient inhibition of IDE may constitute a valid approach to the treatment of diabetes. Moreover, the few studies that have investigated this topic appear to support contradictory conclusions. On the one hand, IDE's established role in insulin catabolism predicts that IDE inhibition should increase the half-life of circulating insulin, an effect that could be beneficial for the treatment of diabetes. This idea is supported by a body of work in vivoinduce a diabetic phenotype. First, a widely used rodent model of diabetes—the Goto-Kakizaki (GK) rat IDE gene that decrease the efficiency of insulin degradation IDE gene (IDE-KO mice) were found to exhibit pronounced glucose intolerance as well as hyperinsulinemia Following its secretion from the pancreas, circulating insulin levels are regulated entirely by proteolytic degradation and other catabolic processes. The degradation and inactivation of insulin, in turn, is well established to be mediated primarily by insulin-degrading enzyme (IDE), a structurally and evolutionarily distinctive zinc-metalloprotease To address this topic, we characterized insulin and glucose homeostasis in IDE-KO and wild-type (WT) mice longitudinally, across the first 6 months of life. Confirming earlier work in vivo, we investigated insulin and glucose homeostasis in male IDE-KO mice and WT littermates backcrossed into a pure C57Bl/6J genetic background. We used a longitudinal design, in which a single group of animals was monitored repeatedly at 3 successive ages  in terms of multiple diabetes-relevant parameters. For biochemical analyses, a separate set of mice was harvested cross-sectionally, at 2 and 6 months of age.To elucidate the consequences of IDE deficiency on glycemic regulation As expected given the known role of IDE in insulin catabolism, and consistent with previous findings The emergence of the diabetic phenotype induced by IDE deletion The preceding results suggest that the diabetic phenotype in older IDE-KO mice may represent a compensatory response to chronically elevated circulating insulin. To explore this idea at a biochemical level, tissues were harvested from a separate set of mice at 2 and 6 months of age. Based on evidence from other animal models of hyperinsulinemia To determine whether these biochemical perturbations were associated with functional changes to glucose transport, we conducted glucose uptake assays in primary adipocytes isolated from 6-mo-old IDE-KO and WT mice. Consistent with the reduction in IR levels observed by western blotting, IDE-KO adipocytes showed substantial impairments in insulin-stimulated glucose uptake .in vivoIn the present study, we investigated glucose homeostasis in mice lacking IDE, the principal protease involved in the clearance and inactivation of insulin per se can be a primary cause of insulin resistance. Mechanistically, in light of the finding that IR levels and/or activity are significantly reduced in IDE-KO mice and multiple other models of chronic hyperinsulinemia, we speculate that insulin insensitivity may, in part, result from classic receptor down-regulation—i.e., adaptation to chronically elevated insulin levels.Taken together, these findings have significant implications for both the etiology and the potential treatment of diabetes. In terms of diabetes pathogenesis, our results corroborate several studies suggesting that insulin resistance can arise as a secondary consequence of primary persistent hyperinsulinemia. For instance, repeated administration of insulin (up to 6U/day) to rats over a 2-week period led to reductions in both maximal insulin binding capacity and IR-mediated glucose utilization While the disturbances in IR levels and functionality we observed appear to offer a neat explanation for the emergence of the diabetic phenotype in IDE-KO mice, we emphasize that considerably more study will be required before firm conclusions can be made. For example, until a more comprehensive analysis is conducted, we cannot formally exclude the possibility that deletion of IDE could trigger defects in insulin signaling components that in turn elicit compensatory hyperinsulinemia. Given that IDE is known to degrade other substrates involved in glucose homeostasis and diabetes pathogenesis, including glucagon increased (∼8-fold) relative to WT hepatocytes, with the population of cell-surface IR elevated still further . While a comparable effect was not observed in vivo, this observation implies that hepatic IR levels are indeed regulated by IDE-dependent factors that, if identified, could potentially be exploited to modulate insulin clearance.The reduction in liver IR levels seen in IDE-KO mice are of special interest, because clearance of circulating insulin, which occurs primarily in liver, is initiated and rate-limited by IR-mediated internalization The precise mechanisms underlying the enhancement of insulin signaling induced by transient reductions in IDE are presently unclear. Superficially, this effect might appear to exclusively derive from the slowing of insulin clearance from the circulation (see Ref. 5). However, recent evidence suggests that suppression of IDE activity can also enhance insulin signaling subsequent to the binding of insulin to the IR per se. Moreover, the risks from overdose of an IDE inhibitor would appear to be minimal, since complete inhibition of IDE does not have immediate deleterious consequences in vivo, which will permit a direct test of the anti-diabetic potential of this important new class of protease inhibitor.From a therapeutic perspective, our results support the idea that pharmacologic inhibition of IDE, properly implemented, may represent a viable—even attractive—therapeutic approach to the treatment of diabetes. In terms of effects on insulin signaling, a short-acting, partial inhibitor of IDE would be predicted to exert similar effects as sulfonylureas or similar secretagogues—namely, increasing the area under the curve of circulating insulin, while maintaining normal rhythmicity of secretion. It is fascinating to note in this context that the sulfonylureas were originally believed to act by inhibiting IDE in vivo: by virtue of IDE's role in insulin catabolism, short-term and/or partial inhibition of IDE is expected to enhance the hypoglycemic action of insulin, an effect that in principle could be beneficial for the treatment of diabetes. Conversely, sustained, complete inhibition of IDE in all tissues, by inducing chronic hyperinsulinemia, elicits compensatory changes to insulin signaling that contribute to insulin intolerance and, hence, glucose intolerance. Given the beneficial effects of transient inhibition of IDE on glycemic control observed in this study, pharmacological inhibition of IDE would appear to represent a potentially viable approach to the treatment of diabetes that merits more thorough evaluation in the future.In conclusion, our analysis of IDE-KO mice suggests a natural resolution to the conflicting ideas concerning the consequences of IDE inhibition for glucose homeostasis +/− mice were obtained from the Mutant Mouse Regional Resource Center then backcrossed into the C57Bl6/J background for 9 generations prior to initiation of the study. Mice were fed Teklad S-2335 mouse breeder chow  and males were used for all experiments. This study was carried out in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. The protocol was approved by the Institutional Animal Care and Use Committee of Mayo Clinic Jacksonville (Protocol Number A16810). All efforts were made to minimize suffering.Founder IDESerum insulin levels were determined using the HTRF® Insulin Assay  and detected using a SpectraMax M5e microplate reader  according to manufacturers' recommendations. Blood glucose levels were measured using the Ascencia® ELITE® SL Blood Glucose Monitoring System  according to manufacturer's recommendations. Glucose and insulin tolerance tests were conducted by monitoring blood glucose following i.p. administration of D-glucose (1 g/kg) or human insulin (1 U/kg), respectively. All measurements were obtained from tail blood samples of mice fasted for 6 to 9 h.Western blots were performed as described 2PO4, 2 mM CaCl2, 1 mM MgSO4, 30 mM HEPES, pH 7.4) supplemented with adenosine (200 nM). Glucose uptake was assessed by addition of KRBH buffer supplemented with 2.5 mM 2-D-glucose, 1% BSA, and 1 µM 14C-deoxy-D-glucose  following stimulation with human recombinant insulin (16.7 nM). Reactions were incubated at 37°C and terminated by addition of cytochalasin B. Following partitioning of cellular contents in dinoyl phthalate, radioactivity in the non-aqueous layer was counted using a liquid scintillation counter (Beckman Coulter).Glucose uptake assays were performed in primary adipocytes isolated from epididymal fat pads essentially as described


Weekly disposable soft contact lenses have been widely used recently, but their shield effects against ultraviolet (UV) irradiation remain to be evaluated. This study investigated the bioprotective effects of several weekly soft contact lenses against UVB irradiation on the corneal surface in a mouse model.2/day after anesthesia for a 7-day period, followed by cornea surface assessment for smoothness, opacity, and grading of lissamine green staining. Tissue sections were prepared for hematoxylin and eosin staining and immunohistochemical detection by using antibodies against myeloperoxidase, cytokeratin-5, P63, Ki-67, nuclear factor-kappa B (p65), cyclooxygenase-2, Fas L, and Fas.Fifty ICR mice were randomly divided into five groups: (1) blank control, (2) exposed to UVB without contact lens protection, (3) exposed to UVB and protected with Vifilcon A contact lenses, (4) exposed to UVB and protected with Etafilcon A contact lenses, and (5) exposed to UVB and protected with HEMA+MA contact lenses. The exposure to UVB irradiation was performed at 0.72 J/cm+ polymorphonuclear leukocyte infiltration into the stroma after UVB exposure, in contrast to the intact status of the blank controls. The corneas with Etafilcon A and HEMA+MA contact lenses maintained more cells positive for cytokeratin-5, P63, and Ki-67 compared to those with Vifilcon A or without contact lens protection. Furthermore, less proinflammatory factors, including nuclear factor-kappa (p65), cyclooxygenase-2, Fas L, and Fas, were induced in the corneas protected by Etafilcon A and HEMA+MA.The results showed impaired corneal surface with myeloperoxidaseThis study demonstrated various protective effects of weekly disposable contact lenses against UVB irradiation. The mouse model used in the present study may be used extensively for in vivo assessment of UV shield efficacy. The cornea contributes a transparent front surface to the eye and plays a pivotal role in providing correct refractive power for clear vision. To fulfill this function, a cornea has to allow light to pass through and therefore can undergo phototoxic damage caused by ultraviolet irradiation. Previous literature has shown that excessive ultraviolet (UV) exposure leads to various symptoms on the ocular surface , includiSince ultraviolet photokeratitis has to be avoided, correction of refraction errors with simultaneous prevention of UV-induced damage has been a pivotal concern in the lens design industry. UV-blocking lenses can filter out straight UV transmission to the central cornea but cannot completely protect against peripheral UV light that may also focus on the central cornea . In contWe previously reported that, after excessive exposure to UVB, the mouse cornea showed significant damage such as corneal ulcer, epithelial exfoliation, and polymorphonuclear leukocyte (PMN) infiltration . The mouFifty 6-week-old female ICR mice were purchased from the National Laboratory Animal Center . The mice weighed about 25 g on arrival. They were fed ad libitum and kept under standard conditions with a 12 h:12 h light-dark cycle. All mice were examined with a dissecting microscope  before the experiments. Only mice without anomalies in the anterior segment  were included in the experiments.2, and the exposure time was set at 90 s to reach a total amount of 0.72 J/cm2/day, for a 7-day period in a darkroom .All data were obtained from triple repeats. The data are presented as the means ± standard error of the means (SEMs) and were compared among groups. The corneal smoothness, opacity, and fluorescein staining scores were compared with the Kruskal–Wallis test. The corneal epithelium thickness and the number of infiltrative PNM, P63The effects of UVB irradiation on the corneal surface were first examined. The regularity of a single or multiple ring-shaped light reflected off the cornea surface was used to evaluate corneal epithelial smoothness . IrregulWith lissamine green staining, a large dark blue devitalized ocular surface area was easily identified in the cornea from the UVB group group 2; -c. In coHistological analysis showed damage corresponding to the findings on the corneal surface. The thickness of the corneal epithelial layer was significantly reduced after UVB irradiation group 2; -b compar+ cells into the stroma after UVB irradiation  and the HEMA+MA contact lenses (group 5), compared to the unprotected UVB group , COX-2, Fas, and Fas L . High leUV irradiation is the major environmental risk factor to human eyes -4, causi+ basal cells, Ki-67+ proliferative basal cells, and CK-5+ differentiated cells. Our data also showed that the P63+ basal cells were the last epithelial cell population to survive after the photodamage caused by UVB irradiation for a substantial period, as exemplified by the 7-day period in our mouse model. In contrast, when the corneas were covered with UVB-blocking Etafilcon A contact lenses or HEMA+MA contact lenses, all epithelial cell populations maintained normal cellular properties after UVB irradiation. Corneal epithelial cells with more differentiated characteristics or those undergoing differentiation are likely more vulnerable to photodamage caused by UVB irradiation. Our results also demonstrated that UVB-blocking Etafilcon A contact lenses and HEMA+MA contact lenses provide protective effects on all three epithelial cell populations identified by their respective markers. Second, if UV-blocking contact lenses are effective for protection against UVB-induced photodamage, such protective effects have to persist long enough to be of positive clinical significance. This is particularly important for weekly contact lenses and even more important for monthly contact lenses. In the present study, we demonstrated that Etafilcon A and HEMA+MA weekly disposable contact lenses prevent UVB-induced photodamage under in vivo conditions even after the 7-day UVB irradiation protocol. This UV proof aspect has to be incorporated as a standard procedure for contact lens design, particularly for contact lenses intended for long-term wear. Third, it had been reported that the maximal amount of UVB reaching the human cornea from sunlight could reach approximately 0.18 J/cm2 per hour [2, equivalent to 4 h of daily sunlight exposure. In many circumstances, this UVB dose is close to daily exposure in the real lives of many people. To some professionals, such as lifeguards, this high dose of UVB exposure is a daily routine. Therefore, results of the present study indicate that the use of proper UV-blocking devices can never be overemphasized. Fourth, the percentage of UVB transmittance for each type of contact lens used in this study increased over the 7-day study period with the present experimental protocol. Since the UVB dosage used in this study was equivalent to 4 h of daily sunlight exposure [Although the beneficial effects of some UV-blocking contact lenses, the Senofilcon A contact lens, for example, have been investigated in several population-based studies ,24,25 asper hour . The daiexposure , the potClinically, the corneal surface topographic deviation in different orientations constitutes the main cause of irregular astigmatism ,28. BaseThe molecular mechanisms underlying the UV-blocking effects by contact lenses for the attenuation of apoptotic and inflammatory activities have not previously been fully elucidated. Because NF-κB activation plays a central role in the inflammatory response, growth-modulatory activities, cellular transformation, and cell death processes ,30, UV-b2/day for a 7-day period. The experimental protocol allowed no time for the deletion of oxidants and inflammatory factors induced by such high phototoxic energy or enough time for the repair of the corneal epithelium. Therefore, the damage following UVB exposure represents only acute photokeratitis conditions. For assessment against chronic photokeratitis conditions, the experimental protocol has to be modified.Although the results of the present study have exemplified the use of mouse model for assessing the efficacy of protection by contact lens against UVB, the present model has limitations. First, the mouse is a nocturnal animal and therefore contains a relatively low concentration of ascorbate in the corneal epithelium for UVB absorption compared with a diurnal animal. For example, the level of ascorbate in the rat corneal epithelium is 8 times lower than that in humans ,39. AlthDisposable soft contact lenses are used by millions of people around the world for vision improvement, protection, or cosmetic purposes. Thus, the efficacy of the UV-blocking properties of contact lenses will always be a major concern. Particularly, the biologic efficacy under in vivo conditions will be more informative than physical or in vitro assessments. The mouse model used in our study may act as a platform for assessing in vivo biologic efficacy for new UV-blocking materials intended for manufacturing contact lenses.


The Health Assessment Questionnaire Disability Index (HAQ) and the SF-36 PF-10, among other instruments, yield sensitive and valid Disability  endpoints. Modern techniques, such as Item Response Theory (IRT), now enable development of more precise instruments using improved items. The NIH Patient Reported Outcomes Measurement Information System (PROMIS) is charged with developing improved IRT-based tools. We compared the ability to detect change in physical function using original (Legacy) instruments with Item-Improved and PROMIS IRT-based instruments.P-values, effect sizes (ES), and sample size requirements.We studied two Legacy  Physical Function/Disability instruments , their item-improved derivatives (Item-Improved HAQ and PF-10), and the IRT-based PROMIS Physical Function 10- (PROMIS PF 10) and 20-item (PROMIS PF 20) instruments. We compared sensitivity to detect 12-month changes in physical function in 451 rheumatoid arthritis (RA) patients and assessed relative responsiveness using P < 0.01). The best IRT-based instruments required only one-quarter of the sample sizes of the Legacy (PF-10) comparator (95 versus 427). The HAQ outperformed the PF-10 in more impaired populations; the reverse was true in more normal populations. Considering especially the range of severity measured, the PROMIS PF 20 appears the most responsive instrument.The study sample was 81% female, 87% Caucasian, 65 years of age, had 14 years of education, and had moderate baseline disability. All instruments were sensitive to detecting change (< 0.05) in physical function over one year. The most responsive instruments in these patients were the Item-Improved HAQ and the PROMIS PF 20. IRT-improved instruments could detect a 1.2% difference with 80% power, while reference instruments could detect only a 2.3% difference (Physical Function scales using item improved or IRT-based items can result in greater responsiveness and precision across a broader range of physical function. This can reduce sample size requirements and thus study costs. Successful management of chronic illnesses, such as rheumatoid arthritis (RA), depends in part upon instruments that validly and precisely measure Physical Function (PF) and can guide appropriate intervention. In RA, Physical Function is commonly assessed by the Health Assessment Questionnaire Disability Index (HAQ or HAQ-DI)  and the Improved instrument sensitivity can result from using IRT-based item calibrations, selection of the best items for new instruments, and using individually tailored items for specific uses. Better precision can increase statistical power or hold statistical power constant while decreasing questionnaire burden ,7.The Patient Reported Outcome Measurement Information System (PROMIS) is an NIH Roadmap infrastructure project charged with developing IRT-based patient reported outcome instruments for improved validity and efficiency in experimental and observational studies ,9. Physin = 1,860) were aggregated from exhaustive literature searches and evaluated for attributes including clarity, importance and comprehension, uni-dimensionality, independence, item difficulty, and item information content and were calibrated on more than 20,000 normal and diseased participants [The 154-item PROMIS PF item bank was developed using classic and modern item assessment methods ,14 and iicipants .This study was designed to determine comparative responsiveness and effects on sample size requirements between Legacy, Item-Improved and PROMIS IRT-based instruments. We hypothesized that the modified new instruments would be sensitive to change over 12 months, would assess responsiveness (sensitivity to change) as well or better than Legacy instruments, would be applicable to greater ranges of disease severity, and would require smaller sample sizes than Legacy instruments.English-speaking participants met American College of Rheumatology criteria for RA. Of 521 participants completing initial questionnaires, we studied the 451 (87%) who returned both baseline and 12-month questionnaires. Respondents were 81% female, 87% Caucasian, averaged 65 years of age with 14 years of education, and had a baseline Legacy HAQ score averaging 0.88. The Stanford Institutional Review Board approved the study, and all subjects gave written informed consent.We studied six instruments: the (1) Legacy HAQ and (2) PF-10, (3) Item-Improved HAQ and (4) Item-Improved PF-10, and the (5) PROMIS PF-10 and (6) PROMIS PF-20. The Legacy HAQ and PF-10 ask about ability over the past week. The Legacy HAQ contains 20 items in eight categories  with four response options: "without any difficulty," "with some difficulty," "with much difficulty," "unable to do." The Legacy PF-10 contains 10 items with three response options: "yes, limited a lot," "yes, limited a little," and "no, not limited at all".The IRT-based instruments, the Item-Improved 20-item HAQ and 10-item PF-10 and the PROMIS PF-10 and PF-20 all assess present abilities . Both "Item-Improved instruments" have five-response options: HAQ - "without any difficulty," "with a little difficulty," "with some difficulty," "with much difficulty," "unable to do"; PF-10 - "not at all," "very little," "somewhat," "quite a lot," "cannot do." We term these items "improved" since PROMIS studies document that present tense and a five-item response set improve instrument responsiveness. Thus, the "item-improved" instruments retain the stem of the original items, but have "improved" the tense to "present" and the response categories to "five" (together with minor improvements in clarity and phrasing). The PROMIS PF 10 and 20 contain IRT-based items selected from the PROMIS PF 154 item bank and include Item-Improved HAQ and PF-10 items. The "IRT-based" PROMIS PF 10 and 20 are selected using IRT information content data from over 21,000 subjects to identify the best items and minor qualitative input to ensure that all major areas of Physical Function/Disability were represented in the instrument, with their strongest items. The PF 10 is a subset of the best items in the PF 20.For the analyses which follow, we scored all instruments as the average of all items, either 10 or 20. All instruments were scored on a 0 to 100 scale (100 = worst disability) averaging scores of component items, and reversing direction as appropriate. Participants also completed validated pain and global health scales ,16. The The PROMIS PF-10 instrument contains five original HAQ derivatives and five original PF-10 derivatives selected from the 30 items using IRT and content balancing to include the better functioning items. The PROMIS PF 20 instrument contains six items derived from the HAQ, five from the PF-10, and nine new items from the 124 items in the PROMIS physical function item bank.Items were selected for IRT information content after consideration of content balancing issues by a study group led by M. Rose. These methods were expected to improve all of the original items to a greater or lesser extent, and to improve the modified scales whenever a new item with higher IRT scores replaced a Legacy item.Changes thus are considered evolutionary and to remain buttressed by the hundreds of validation studies that have been performed on the Legacy instruments ,2,10-12.We assessed participants using mailed questionnaires, randomly ordering instruments within questionnaires to eliminate order effects. We followed established Arthritis Rheumatism and Aging Medical Information System protocols for follow up and quality control .The study endpoints were the 12-month change in scores using each instrument, representing an average progression of disability in rheumatoid arthritis over a year. We studied the differences between instruments rather than treatments; thus the effect-size is expected to be much smaller than the effect of an RA treatment. Observed change scores are a function of the "true change" and of the error terms surrounding estimation of the baseline and follow-up values. A more precise instrument will have smaller standard errors, allowing a more precise estimation of the true change. We used the quantitative one-year change in Physical Function scores under usual care; these changes include the progression of RA, the progression of co-morbid chronic illness, and the progression of frailty related to aging.P-values (pair-wise t-tests), computed Cohen's [We assessed participants' 12-month Physical Function change score from baseline and between instruments (relative instrument sensitivity) with exact  Cohen's  and Guya Cohen's  effect s Cohen's , and the Cohen's .For between-instrument comparisons, we computed sample sizes required per study arm for 80% power, with an alpha of 0.05, given the delta that was observed. We used bootstrapping methods to determine confidence limits for the change score SDs and computed the confidence limits for sample size requirements from the confidence limits of the change score SD.P < 0.05 level given 80% study power. Power for this study is more than sufficient to detect a change equal to or greater than the minimal clinically important difference (MCID) for Physical Function, consistently cited for the HAQ at 0.22 units or 7% of the possible change [Data are described by proportions and means (± SD). We defined non-inferiority as when neither instrument was statistically superior to the other at the e change . We usedSince all instruments were scored identically and resulted in similar change scores, the exact level of MCID chosen is of only peripheral relevance. The minimum detectible difference (MDD) is more directly relevant to correlations between change scores of the six instruments.Correlations between instruments were strong and all changes were in the same direction and of similar magnitude, indicating that all instruments are estimating the same, or a similar, latent trait. Differences between instruments are consistent with the SD of the change score, which is smaller in the Item-Improved and IRT-based scales.P = 0.31) and global health scores (P = 0.02) were additionally studied as reference domains. All instruments were highly responsive to detection of change in function over 12 months (P < 0.05), except for the pain scale. With the Legacy and Item-Improved HAQ instruments, there was little difference in scoring by averaging eight categories versus 20 items, and we present the average scores for all items for all instruments studied to facilitate comparisons, as recommended by PROMIS. [P-values but more importantly in the metrics which follow.Table  PROMIS.  StandardTable Figure The fit between the severity distribution of the study population and the range of coverage of the instrument is centrally relevant to responsiveness, standard deviation of change, and sample size requirement issues. An instrument with items about eating, dressing, and grooming will not be sensitive to change in a population of college athletes since most will be able to do these activities easily. An instrument with items based around strenuous and difficult items about walking and climbing stairs will not perform well in a population with longstanding RA since most will have difficulty in many categories.To illustrate the role of floor and ceiling effects in reducing study power, Figure The Item-Improved HAQ outperforms the Item-Improved PF-10 when functional abilities are more than 1.4 SD units below the population mean, while the opposite is true when abilities are better Figure . The PROItem-improvement processes and use of IRT-based items can lead to improved instrument performance. In turn, this can make clinical research more efficient and less costly by reducing required sample sizes. The Legacy PF-10 is the most extensively used Physical Function scale and is a valid benchmark for assessing change. However, it is limited, having only 10 items and three response options, which render it less sensitive than 20-item scales or scales with five response options.The Item-Improved HAQ performed essentially as well as the PROMIS PF 20 in the RA patients studied. This initially unexpected result was partly due to identical response options in the two instruments and to a number of shared items. More importantly, however, these RA patients had average disease severity one to two SDs below the mean, where the HAQ is most sensitive. Where the PROMIS PF 20 is strongest in comparison to the HAQ is in the one-half SD range near the population mean  has generally been utilized for RA and other serious chronic illness, and the PF-10 for more normal populations. The IRT-based PROMIS PF 20, considering all levels of impairment, outperforms the other instruments.PROMIS and other CAT applications, better at estimating function at the extremes, should provide substantial further improvement ,9. PROMITheoretically, a nearly equivalent result may be obtained by using brief forms generated from the same calibrated item bank and tailored for strong reliability in a particular severity (theta) range matched to the study population. Such brief forms may also be developed through simulated CAT research, where the paths most frequently chosen identify the best items ,9.These data raise the issue of floor and ceiling effects . PROMIS Additional advantages accrue to PROMIS instruments that strengthen our confidence in recommending their use. The PROMIS process , beginniTo our knowledge, this is the first randomized study of alternative PRO instruments to document positive results with IRT-based instruments over traditional ones. We all are used to studies comparing treatments, not instruments, where effect sizes are often 0.6 or higher, rather than 0.06. This requires a different perspective, since improved PRO instruments are not interventions, but are more precise outcome measurement tools, much like a more precise sedimentation rate or more precise measurement of blood pressure. The improved precision effect may be smaller than the Minimally Clinically Important Differences (MCID) for interventions. They do, however, make it easier to detect whether an MCID is present or not. This, in turn, results in more efficient clinical research, requiring fewer subjects, fewer centers, shorter recruitment periods, reduced time to study completion, and easier monitoring of the trial, all very important considerations.The "present" of Physical Function assessment embodies new instruments derived from improved items and employing better item selection, which in turn results in lowering sample size requirements and improving efficiency. If 60 billion dollars is spent annually in the United States on clinical trial research and half of this (30 billion) is driven by per patient costs as opposed to administrative costs, and if one-fourth of these (7.5 billion) use quality-of-life patient-reported outcomes  as primary endpoints, and if sample size requirements may be readily reduced by a factor of 2, then the unnecessary costs for using larger than necessary sample sizes may be in the range of three to eight billion dollars in the United States annually ,24.The "future" will include items and instruments that assess the floor and the ceiling and items and instruments tailored to specific ranges of functional ability. This will encourage broader functional status assessment and will enable CAT instruments with even broader coverage and greater precision of measurement.CAT: computerized adaptive testing; HAQ: Health Assessment Questionnaire; HAQ-DI: Health Assessment Questionnaire Disability Index; IRT: item response theory; IRT-Based: items which have been calibrated by IRT within our item bank so that the better-performing items may be selected; Item-Improved: changes to items intended to improve their performance by altering parameters such as time frame and response options while retaining the same item stem; MCID: minimal clinically important difference; MDD: minimum detectable difference; NIH: National Institutes of Health; PF: Physical Function; PF-10: Physical Function 10-item short form from the SF-36; PROMIS: Patient-Reported Outcomes Measurement Information System; RA: rheumatoid arthritis.The authors declare that they have no competing interests.JF conceived and planned the study and participated in all aspects of its development. EK participated throughout, with particular emphasis upon analytic issues. MR participated throughout, and was responsible for IRT analyses and interpretation. BL participated throughout, and was responsible for many analyses and statistical issues. BB participated in design, analysis and manuscript development. All authors read and approved the final manuscript.