P < 0.025). GMV increase in the left hippocampus was associated with improvement of depressive symptoms in Tp2–Tp3 (P < 0.05). Our findings suggest that different temporal lobe structures are associated with early antipsychotic and late antidepressant effects of ECT.Recent studies examining electroconvulsive therapy (ECT) have reported that early sessions can induce rapid antidepressant and antipsychotic effects, and the early termination of ECT was reported to increase the risk of relapse. We hypothesized that different neural mechanisms associated with the therapeutic effects of ECT may be involved in the different responses observed during the early and late periods of ECT treatment. We investigated whether these antidepressant and antipsychotic effects were associated with temporally and spatially different regional gray matter volume (GMV) changes during ECT. Fourteen patients with major depressive disorder, with or without psychotic features, underwent 3-Tesla structural magnetic resonance imaging scans before (time point [Tp] 1), after the fifth or sixth ECT session (Tp2), and after ECT completion (Tp3). We investigated the regions in which GMV changed between Tp1 and Tp2, Tp2 and Tp3, and Tp1 and Tp3 using voxel-based morphometry. In addition, we investigated the association between regional GMV changes and improvement in depressive or psychotic symptoms. GMV increase in the left superior and inferior temporal gyrus during Tp1–Tp2 was associated with improvement in psychotic symptoms ( Courses of ECT are typically delivered over a total of 6–12 sessions, with two or three sessions per week. Symptom improvements observed during the early and late periods of ECT may be associated with different mechanisms. A rapid and strong antidepressant effect can be observed during the early period, typically before six sessions2, whereas the termination of ECT before attaining remission has been reported to increase the risk of relapse3. Several reports have indicated that antipsychotic effects also begin to emerge in the early period, as suggested by better4 and faster5 responses to ECT in patients who have MDD with psychotic features, in comparison with those without psychotic features. Separate mechanisms may produce the rapid and strong therapeutic effects observed during the early period from those related to relapse prevention during the late period of ECT.Electroconvulsive therapy (ECT) is considered a rapid and reliable treatment for major depressive disorder (MDD)14. However, it is unclear at which point during the course of ECT this regional volume change occurs. Two previous studies reported no changes in volume before and after the first or second ECT sessions14. Therefore, volume changes may occur at or after the midpoint of the course. This possibility is in accord with the notion that therapeutic effects typically appear after the first three to six ECT sessions2.To date, a number of magnetic resonance imaging (MRI) studies have revealed that gray matter volume (GMV) increases after ECT compared with baseline in the limbic regions, prefrontal cortex, and temporal cortex16. However, two meta-analyses revealed that such a volume increase was not associated with improvement in depressive symptoms16. Moreover, it is currently unclear whether an increase in GMV is associated with improvement of psychotic symptoms in MDD. Only a small number of studies have included patients who have MDD with psychotic features14. However, to date, no studies have assessed the differences in volume increase between patients who have MDD with and without psychotic features.It is currently unclear which regional volume changes are associated with improvement in the symptoms of MDD. Increased GMV in the hippocampus (HC) is currently the most consistent finding after ECTThus, it is currently unclear whether there are differential associations between early and late therapeutic effects of ECT and regional GMV changes. To address this issue, we performed a longitudinal assessment of patients with MDD, at three time points: before, during, and after ECT. At each time point, we evaluated depressive symptoms with or without psychotic features and structural MRI images.The aims of the study were to investigate: (i) when during the course of ECT regional GMV changes take place; (ii) whether regional volume changes in the early or late period of an ECT course are associated with depressive symptom improvement; and (iii) whether there is a difference in GMV changes between patients with and those without psychotic symptoms.17. As for the inclusion criteria, all patients met the diagnosis of a depressive episode according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision or Fifth Edition (DSM-IV-TR or -5) and did not respond adequately to two or more different antidepressant treatments of more than 4 weeks’ duration. Exclusion criteria for all individuals were a history of severe medical conditions; current substance abuse; or a history of seizure disorder, cerebrovascular disease, or brain injury. Thirteen patients were taking one or more antidepressant medications at the time of the study: three patients were taking tricyclic antidepressants, nine were taking selective serotonin reuptake inhibitors, one was taking selective serotonin noradrenaline reuptake inhibitors, and one was taking other types of antidepressants. Seven patients exhibited psychotic features and the other seven did not exhibit psychotic features.Fourteen inpatients were recruited from the Department of Psychiatry at Kyoto University Hospital, Kyoto, Japan. All patients met the application criteria of ECT, according to American Psychological Association taskforce guidelinesThe study was approved by the Committee on Medical Ethics of Kyoto University and was implemented in accordance with the Declaration of Helsinki. Written informed consent was obtained from all participants.18; the subsequent intensity was adjusted based on seizure quality . ECT sessions were performed until the patient reached a plateau of improvement over the previous two sessions.Bifrontotemporal ECT was administered once or twice a week using a brief-pulse square-wave ECT device . Benzodiazepines and mood stabilizers  were discontinued before ECT, but antidepressants and antipsychotics were continued. Propofol  or thiopental sodium  were used to induce anesthesia, and succinylcholine chloride  was used to induce muscle relaxation. The stimulus intensity for the first ECT session was determined according to the half-age stimulation strategyWe assessed clinical symptoms and acquired MRI data at three time points; before the first ECT session, after the fifth or sixth ECT session, and after completing all ECT sessions. These time points were denoted Tp1, Tp2, and Tp3, respectively.Depressive symptoms were evaluated using the Hamilton 17-item Depression Rating Scale (HDRS). Psychotic features were defined as the presence or absence of delusions and/or hallucinations during an episode of major depression, according to the DSM-IV-TR or DSM-5.Each patient was scanned three times at each time point using a 3-Tesla MRI scanner with a 32-channel head coil . High-resolution anatomical images were acquired in the sagittal mode using three-dimensional (3D) T1-weighted magnetization-prepared rapid acquisition of a gradient echo .The first scan was performed within 1 week prior to the first ECT and the final scan was done within 1 week of the final ECT.19. Preprocessing was performed using the Statistical Parametric Mapping software package , and its toolbox, the Computational Anatomy Toolbox  in MATLAB 2016b . MPRAGE data were visually checked for gross anomalies and artifacts, and reoriented to adjust image origins at the anterior commissure. Images were segmented into gray matter, white matter, and cerebrospinal fluid. The segmentation process was further extended by accounting for partial volume effects, applying adaptive maximum a posteriori estimation and using a hidden Markov random field model. Segmented gray matter images were normalized to Montreal Neurological Institute space using a template that had already been obtained with Diffeomorphic Anatomical Registration Through Exponentiated Lie algebra20 and the geodesic shooting algorithm21 in CAT12. Modulation was applied to convert the voxel values of tissue density to measures of volume. Finally, modulated gray matter images were smoothed using a Gaussian kernel of 8 mm full-width at half-maximum.Longitudinal brain volume changes were evaluated using voxel-based morphometryWe did not use a longitudinal preprocessing pipeline implemented in CAT12 because this pipeline required all time-point data for calculation; that is, the Tp3 image was required to calculate the difference between Tp1 and Tp2, which might reduce sensitivity.t-tests or chi-square tests, as appropriate. Changes in HDRS scores were evaluated using repeated measures one-way analysis of variance (ANOVA) and paired t-tests for post hoc testing. Additionally, HDRS score changes between Tp1–Tp2 and Tp2–Tp3 were compared using unpaired t-tests, to estimate differences between early and late antidepressant effects of ECT. Results were considered statistically significant at P < 0.05. All analyses were conducted using IBM SPSS 22 .Demographic and behavioral data were analyzed using (i)Regional GMV change during the course of ECTP = 0.001 and cluster-wise family-wise error (FWE) rate of P < 0.05. Age, sex, total intracranial volume, and psychotic symptoms were included as covariates. Post hoc analyses were performed as paired Student’s t-tests comparing Tp1 versus Tp2, Tp1 versus Tp3, and Tp2 versus Tp3. The paired Student’s t-tests were performed using a CFT of P = 0.001 and a cluster-wise FWE of P < 0.05. Then, the resulting images were binarized to create inclusion masks, and these masks were applied to the ANOVA, described above. Cohen’s d effect size21 of significant volume changes was calculated.To investigate regional GMV changes during the course of ECT, one-way repeated measures ANOVA, including all 14 patients, was performed, using SPM12, with F-contrasts testing of Tp1 versus Tp2, Tp2 versus Tp3, and Tp1 versus Tp3. Statistical significance was tested with a cluster-forming threshold (CFT) of For the clusters detected in analysis (i), two subsequent region-of-interest (ROI) analyses were performed.Subsequent ROI analysis (i)-a23. Voxel values were extracted from significant clusters that were identified in the whole-brain analysis (i), and the relative volume changes at Tp2 and Tp3 were calculated as the ratio between the voxel values at Tp2 and Tp3, respectively, and the voxel value at Tp1. Relative volume changes were independent variables.To estimate the association between relative volume changes between Tp1 and Tp3 and the total number of ECT sessions, a simple regression was performed, as recent mega-studies have reported a significant positive slope between volume changes and the total number of ECT sessionsSubsequent ROI analysis (i)-bTo estimate the association between relative volume changes in the cluster and changes in HDRS scores, the relative volume changes were calculated, as described for ROI analysis (i)-a, and the changes in HDRS scores were calculated as a percentage of the change in HDRS scores between two time points. Then, simple regression analyses were performed, using the change in the HDRS score as the explanatory variable.(ii)Association between regional GMV and changes in depressive symptom severity24. A statistical significance threshold of P < 0.05. Because the TFCE toolbox does not support the ANOVA design, we did not use TFCE in (i).For periods in which we found significant changes in HDRS scores, we examined the regions in which volume changes were associated with changes in depressive symptoms in whole-brain analysis on SPM12, for all 14 patients. First, subtraction images between Tp1 and Tp2 and between Tp2 and Tp3 were calculated using the ImCalc function of SPM12. Second, changes in HDRS scores between Tp1 and Tp2 and between Tp2 and Tp3 were calculated as subsequent ROI analysis (i)-a. Finally, we performed multiple regression analyses in SPM12, using subtraction images as the dependent variables and HDRS change, presence/absence of psychotic features, age, sex, and total intracranial volume as the independent variables. Threshold-free cluster enhancement (TFCE) was used for multiple comparison corrections, using the SPM12 TFCE Toolbox(iii)Association between regional GMV changes and the presence/absence of psychotic symptomst-test in depressive patients with/without psychotic symptoms (N = 7 in each group) using subtraction images between Tp1–Tp2 and between Tp2–Tp3. TFCE was used for multiple comparison corrections. A statistical significance threshold of P < 0.05 was divided by the number of comparisons. Age, sex, and total intracranial volume were included as covariates.As in (ii), for periods in which psychotic symptoms improved, we examined the association between changes in regional GMV and changes in psychotic symptoms. We applied a two-sample P < 0.001; Tp2–Tp3, P < 0.01; Tp1–Tp3, P < 0.0001). Thus, we included both periods (Tp1–Tp2 and Tp2–Tp3) in the analysis in (ii). The changes in HDRS score did not differ between Tp1–Tp2 and Tp2–Tp3 (P = 0.23).Demographic data are summarized in Table 5, age, age at onset, and HDRS score at Tp1 were significantly higher in patients with psychotic depression compared with those who had non-psychotic depression.In accord with previous studiesBecause psychotic symptoms were remitted by Tp2 in all patients with psychotic depression, we limited the analysis in (iii) to the period between Tp1 and Tp2.N = 14) showed significant GMV changes during the ECT course in the left hippocampus (L-HC), right hippocampus (R-HC), left insular cortex (L-IC), and subcallosal cingulate cortex (SCA) (CFT of P = 0.001 and cluster-wise FWE of P < 0.05)   Fig. . Post ho05) Fig. . The effSubsequent ROI analysis (i)-aF = 0.086, P = 0.77, with an R2 of 0.0071; R-HC: F = 0.029, P = 0.87, with an R2 of 0.002, L-IC: F = 0.84, P = 0.38, with an R2 of 0.065; SCA: F = 0.28, P = 0.61, with an R2 of 0.023; Fig. A simple linear regression was performed to estimate volume changes between Tp1 and Tp3, based on the total number of ECT sessions. No significant regression equation was found [L-HC: Subsequent ROI analysis (i)-bF = 1.35, P = 0.27, with an R2 of 0.10; R-HC: F = 0.56, P = 0.47, with an R2 of 0.045; L-IC: F = 0.069, P = 080, with an R2 of 0.0057; SCA: F = 4.42, P = 0.057, with an R2 of 0.27; Fig. A simple linear regression was performed to estimate volume changes based on decreases in HDRS. No significant regression equation was found [L-HC: P < 0.05; Fig. Decreases in HDRS scores, between Tp2 and Tp3, were significantly associated with increases in GMV, in the cluster located in the L-HC (FWE of N = 7 in each group) between Tp1 and Tp2, in which psychotic symptoms were improved, indicating an increase in volume of the left superior and middle temporal gyrus (L-STG/MTG) in patients with psychotic features as compared with those who did not have psychotic features   Fig. .Fig. 3AsEarly and late periods of ECT had different therapeutic effects.GMV increases were found in several regions, including the bilateral HC, at the end.The GMV increase in the L-HC was associated with a decrease in depression severity during the late period of the ECT course.In comparison with patients who had non-psychotic depression, patients with psychotic depression exhibited GMV increases in the L-STG/MTG during the early period of ECT.To our knowledge, this is the first study to demonstrate that different periods during the ECT course are associated with increases in GMV in different regions, as well as being associated with different therapeutic effects. The present study revealed four main findings:5. However, we did not observe significant differences in the antidepressant effects of ECT between the early and late periods.We found that the early period of ECT was associated with both antidepressant and antipsychotic effects whereas the late period was associated with antidepressant effects only. These results are compatible with those of previous studies reporting that antidepressant and antipsychotic effects begin to emerge during the early period of ECT14. We did not find a GMV increase at Tp2 as compared with Tp1, but the effect sizes of regional volume changes between Tp1 and Tp2 and Tp2 and Tp3 were large21. Thus, regional GMV increased gradually during the entire course of ECT, resulting in the largest regional volume at the end of the ECT course -b identified no significant associations between the bilateral HC and HDRS increases between Tp1 and Tp3 Fig. , but our-HC Fig. , which w-HC Fig. . Thus, w28.Our study design, using three time points, enabled us to detect this symptom–structure association. Recent MRI studies in humans have revealed that a volume increase in the dentate gyrus after ECT was associated with improvement in depression severity31. Taken together, these findings suggest that ECT may exert antidepressant effects via neurogenesis in the HC, particularly the dentate gyrus.In addition, animal model studies have reported that neurogenesis in the dentate gyrus is necessary to induce antidepressant effects32. One study reported that ECT-induced cognitive impairment was associated with a volume increase in the HC33, whereas another study, which focused on the L-HC, did not find any such association34. Here, we performed two additional analyses to determine whether such an association existed. We investigated the association between changes in cognitive function, as assessed by the MMSE, and volume changes in the L-HC that were identified as significant in the following two analyzed results: (i) pre- and post-ECT comparisons ons Fig. . However13. Two studies that included participants with a high proportion (53% and 26%) of psychotic depression reported GMV increases in the STG/MTG, respectively12.The current results revealed that remission of psychotic symptoms in the early period of ECT was associated with GMV increases in the STG and MTG Fig. . The cur37. In particular, reduced left STG/MTG GMV has been correlated with the increased severity of auditory hallucinations38. The current results showed that the GMV in the left STG/MTG could be normalized by ECT in the group with psychotic features during the early period. This result was in line with the clinical reports that patients with psychotic depression are more likely to respond to ECT earlier than patients without psychotic depression5. In contrast, the non-psychotic group experienced a reduction in STG/MTG lobe volume during the early period, although the reasons for this change are unclear because ECT increases the volumes of a wide range of regions23. However, volume reduction in the temporal lobe, which could be associated with depression39, may precede volume increases due to ECT because volume increases require a sufficient number of ECT sessions. Differences in the GMV response to ECT were not observed in any regions other than the STG/MTG. Volume increases associated with ECT may be specific to the left STG/MTG, which have also been associated with psychotic symptoms. Our hypothesis suggests that the early antipsychotic effects of ECT were associated with the increased GMV observed in the left STG/MTG, and that the subtype of depression characterized by psychotic features could have a structural brain underpinning. The association between ECT and psychotic symptoms requires further study.Previous studies reported reduced GMV in the STG/MTG of depressive patients with psychotic featuresThe current study involved several limitations that should be considered. First, given the small number of patients, the results of the current study should be interpreted cautiously. Second, we were unable to recruit controls  with whom to compare changes in regional GMV during the observation period. Third, nearly all patients in the current study were taking medication; thus, we cannot exclude the possibility of medication effects. Fourth, we did not have a measure of the microstructural change induced by ECT. Advanced methods, such as ultra-high field MRI, myelin maps, neurite orientation dispersion, and density imaging would be useful to elucidate the microstructural basis of ECT in depression.Using a study design with assessment at three time points, we revealed that the HC volume increased slowly during the course of ECT. In addition, we found that the early antipsychotic and late antidepressant effects of ECT were associated with volume increases in the STG/MTG and HC, respectively. Thus, ECT may exert antidepressant effects through its effect on the HC. Future studies should investigate the mechanisms underlying the effects of ECT using advanced imaging methods that are sensitive to microstructural changes.Supplemental material


Total PSQI score, TST, SE, and time spent in LS or DS were not significantly associated with FA or MD (p>0.13). Percent time spent in REM sleep, but not quantity of light and deep sleep or subjective/objective measures of sleep quality, positively predicted white matter microstructure integrity. Our results highlight an important link between REM sleep and brain health that has the potential to improve sleep interventions in the elderly.There is increasing awareness that self-reported sleep abnormalities are negatively associated with brain structure and function in older adults. Less is known, however, about how objectively measured sleep associates with brain structure. We objectively measured at-home sleep to investigate how sleep architecture and sleep quality related to white matter microstructure in older adults. 43 cognitively normal, older adults underwent diffusion tensor imaging (DTI) and a sleep assessment within a six-month period. Participants completed the PSQI, a subjective measure of sleep quality, and used an at-home sleep recorder  to measure total sleep time (TST), sleep efficiency (SE), and percent time in light sleep (LS), deep sleep (DS), and REM sleep (RS). Multiple regressions predicted fractional anisotropy (FA) and mean diffusivity (MD) of the corpus callosum as a function of total PSQI score, TST, SE, and percent of time spent in each sleep stage, controlling for age and sex. Greater percent time spent in RS was significantly associated with higher FA (β = 0.41,  The prevalence of neurodegenerative diseases is increasing as the world’s population continues to age . The numMore than half of the older adult population experiences chronic sleep disturbances including increased sleep fragmentation, difficulty falling asleep, and decreased total sleep duration ,3,4. MorSleep also appears to be directly linked to age-related changes in brain structure. In functionally intact, older adults, self-reported poorer sleep quality and shorter sleep duration on the Pittsburg Sleep Quality Index (PSQI) are associated with greater reduction in total cerebral gray matter, ventricular expansion, as well as reduced hippocampal and thalamic volume on structural T1 imaging ,15. AddiAlthough many studies have reported on the relationship between sleep and grey matter, less is known about sleep’s relationship with white matter in older adults. White matter is frequently injured in sleep disorders such as obstructive sleep apnea or REM sleep behavior disorder ,18, and While the findings reported by Sexton et al. are compelling, current sleep research has been limited by the sole use of subjective, or self-reported, sleep measures such as the PSQI or sleep diaries. Poor to moderate correlations have been measured between self-reported and objective sleep measures –23. In aObjective sleep measures quantify participants’ overall sleep quality  while providing nightly information on sleep architecture and fragmentation . Polysom43 community-dwelling older adults were recruited from the longitudinal Hillblom Healthy Aging Network at the University of California, San Francisco (UCSF) Memory and Aging Center. Study exclusion criteria followed protocols described by Staffaroni et al. . ExclusiAll participants completed a general research visit through ongoing observational studies in which cognitively healthy older adults participate in at the UCSF Memory and Aging Center . These visits included neuropsychological testing, neurological examination, and Clinical Dementia Rating . A “clinically normal” diagnosis was assigned by a formal committee if at least 2 of the following criteria were met: no cognitive concerns during the neurological examination, a participant performed within expected ranges for their age and education on neuropsychological assessments, and the study informant / partner did not raise any concerns over the participant’s cognition during the CDR interview. Blood samples were processed to obtain measures of cholesterol levels  ratio), HOMA-IR, and Apolipoprotein E (ApoE) genotype. In addition to a full medical history and general neurological examination, the neurologists measured participants’ weight, heart rate, and systolic blood pressure. Due to collection procedures, weight, heart rate, and blood pressure were not measured on all participants. A diagnosis of hyperlipidemia (HLD) was determined by chart review (self-reported diagnosis of HLD and/or cholesterol-lowering medications listed) and by cholesterol:HDL value (>3.5).To assess risk of sleep apnea, participants completed the Berlin Sleep Apnea Questionnaire (BQ) . The BQ Participants were asked to wear a wireless sleep-monitoring device  in their habitual sleeping environment for up to 10 nights. Participants were instructed to place the headband on only when they were about to start trying to fall asleep. They were also instructed to keep the headband on throughout the night, and only remove it when they were ready to get up to start their day. The headband is lightweight with three dry electrodes at approximately Fp1, Fpz and Fp2. Signals are emitted from the headband to a small bedside device, which processes the electrophysiological signals in 30 second epochs using a proprietary neural network  to assess latency to sleep onset, duration of wake after sleep onset, light sleep (stages 1 and 2 Non-REM sleep), deep sleep (stage 3 Non-REM sleep) and REM sleep. Previous papers have shown relatively high levels of agreement between REM sleep identified by the Zeo autoscoring algorithm versus polysomnography scorers .The first night of data collection was removed from the dataset to account for habituation to wearing the headband device. To be included in analyses, participants needed at least three additional nights of usable data, where the amount of unscored data was less than 45 minutes across the night. The unscored data may have included periods when the participant went to the restroom where signal transmission to the device may have been lost.Light sleep, deep sleep and REM sleep were analyzed as a percent of total sleep. Sleep efficiency was calculated as the percentage of time spent asleep divided by the total time in bed trying to sleep.All participants completed an MRI scan within 6 months of their sleep study (either before or after). Participants were scanned at the UCSF Neuroscience Imaging Center on a Siemens Trio 3T scanner equipped with a 64-channel head coil. Volumetric MPRAGE sequences were used to acquire T1-weighted images of the entire brain . Diffusion-weighted images were acquired using a single-short spin-echo sequence with the following parameters: repetition time = 5300 ms; echo time = 88 ms; inversion time = 2500 ms; flip angle = 90; field of view = 256*256 mm; 2 diffusion values of b = 0 and 1000 s/mm; 12 diffusion directions; 4 repeats; 40 slices; matrix size = 128*128;voxel size = 2 mm*2 mm; slice thickness = 3 mm; and generalized auto-calibrating partial parallel acquisition = 2.http://dti-tk.sourceforge.net) based on previously published methods [DTI processing began with denoising . The b = methods . DTI-TK  methods ,37. Globp = 0.04, global MD: β = -0.38, p = 0.01). Full models analyzing the relationship between REM sleep and global FA/MD are found in The corpus callosum (CC) region of interest (ROI) was extracted from the ICBM-DTI-81 white matter labels and tract atlas . CC FA, All statistical analyses were conducted using Stata Statistical Software . Participants with less than three nights of sleep data were excluded from the analyses. To look for outliers in the sleep data, DTI data, and vascular risk measures, the range of values were assessed to ensure all values were biologically possible. Next, datapoints were visualized with histograms and outliers were identified as datapoints over 3 standard deviations from the mean. Based on this method, one outlier was identified. On the PSQI measure, one participant had a score of 17 (0.3 above the 3 standard deviation cut-off). As the PSQI represents a total score from a self-reported survey where 17 is a reasonable response, it was determined appropriate to retain this score in our analyses. No other outliers were found. Thus, all available data points were included in analyses. Due to study protocols, some participants had missing data. Participants with missing data were only excluded from the analysis directly affected by the missing data point and retained in all other analyses.To understand the relationship between sleep and DTI measures, we performed multiple regressions controlling for age and sex (Model 1). For Model 1, separate regressions were conducted with each of the sleep metrics (PSQI (continuous measure), sleep efficiency, total sleep time, and percent time spent in light sleep, deep sleep, and REM sleep) individually as the predictor, and with the dependent variables being FA, MD, AD, or RD of the CC, as well as global FA or MD in a separate sensitivity analysis. For any of these relationships that were statistically significant, we fitted two additional regression models (Model 2 and Model 3). For Model 2, we considered several potential vascular health confounds including HOMA-IR, evidence of hyperlipidemia, systolic blood pressure, physical activity (PASE), and sleep apnea risk as measured by the BQ. To ensure that we accounted for potential collinearity of these measures, we assessed the variable inflation factor (VIF) for all covariates under consideration. HOMA-IR and hyperlipidemia were highly collinear (VIFs>8.7). As hyperlipidemia is used more often in clinical contexts, HOMA-IR was removed as a covariate. After this step, all VIFs were below 2, which, based on Craney et al. , enabledParticipants had a mean age of 75 ± 4.51 years (66–84 years), mean education of 18 ± 2.1 years (13–20 years), and 27 participants identified as female. All participants were cognitively normal with a mean mini-mental state examination (MMSE) of 29 ± 1.19 (26–30) and CDR box score of 0. A total of 7 participants took sleep modifying medications . Additional data describing DTI values and vascular risk factors are presented in Participants included in our study had an average PSQI of 5.31 ± 3.79 (1–17). 13 out of 42 participants with PSQI data had a PSQI score greater than 5 and were classified as “poor” sleepers. PSQI data, however, were analyzed as a continuous variable. 6 out of 41 participants were classified as “high risk” for sleep apnea based on the BQ. Across the nights, participants spent an average of 52.2% ± 8.73% (28.2–68.7%) in light sleep, 7.75% ± 4.01 (0.73–17.9%) in deep sleep, and 26.6% ± 7.79% (11.0–47.0%) in REM sleep. Additionally, participants had a mean total sleep time of 6.45 hrs ± 0.81 hrs (4.27–7.83 hrs) and mean sleep efficiency of 84.2% ± 32.3% (64.3–97.25%) .We present associations with callosal DTI as a proxy for global white matter integrity due to its susceptibility in various neurodegenerative disease processes . We perfp = 0.007) and CC MD  (p = 0.008), but not CC AD  (p = 0.04), MD , AD , and RD  . Of note = 0.32) , Model 1EM sleep , Model 1EM sleep .p’s > 0.20) (The relationships between REM sleep and CC FA/MD/RD were independent of vascular risk factors and ApoE status (p = 0.277). Further, the relationship between REM sleep and CC FA/MD remained significant after removing the 7 individuals taking sleep modifying medication .There were no group differences in percent of REM sleep between those taking sleep modifying medications and those who do not  and sleep efficiency  were not significantly associated with CC FA or CC MD .Objectively measured total sleep time  in light sleep, deep sleep, and REM sleep, related to white matter microstructure. Surprisingly, we found that greater time spent in REM sleep (percent) was significantly related to higher CC FA, lower CC MD values, and lower CC RD values. Our results indicate that increased duration of REM sleep relates to healthier white matter microstructure in cognitively normal older adults, independent of sleep apnea, vascular, or genetic risk factors.Notably, total PSQI score, a subjective measure of sleep quality, did not relate to CC FA or CC MD in our cohort of cognitively normal, older adults. These results are inconsistent with previous research findings that report a significant relationship between total PSQI score and DTI in healthy older adults and individuals with insomnia ,40. Our Our results are consistent with recent studies investigating the relationship between measures of sleep efficiency and sleep duration with brain DTI measures ,51. In oAlthough previous research indicates an association between subjective measures of sleep quality (e.g. PSQI or sleep diaries) and white matter microstructure, it is unsurprising that few studies have found similar results when objectively measuring sleep quality. Several studies have reported a high-level of disagreement between objective and subjective sleep quality measures in older adults –23. SubjThere are several factors that could have contributed to our finding that the percent time spent in REM sleep was associated with white matter FA and MD in cognitively normal healthy older adults. We included many of these in our analyses to determine if the finding may be specific to REM sleep itself or to other contributing factors such as vascular health, obstructive sleep apnea, and ApoE status. These are discussed below.Research has shown that white matter microstructure reduces with age and is sensitive to vascular risk modifiers such as hypertension, high body mass index (BMI), high cholesterol, and low exercise –54. NotaFurthermore, moderate to severe obstructive sleep apnea (OSA) contributes to cerebral white matter change . OSA is ApoE-ε4 carriers are at higher risk for cognitive decline than their non-ε4 counterparts . CognitiThe potential mechanisms underlying the relationship between REM sleep and brain white matter microstructure remain unclear mechanistically. Oligodendrocyte precursor cells (OPCs) develop oligodendrocytes, which are the cells that produce myelin. In studies of OPCs and sleep, REM sleep alone was positively correlated with OPC proliferation . Though REM sleep has also been associated with regulating the chemical and physical properties of the blood brain barrier (BBB). One study found that mice deprived of REM sleep had increased BBB permeability . This inHigh amplitude-theta wave bursts are characteristic of REM sleep , and a rThis study was limited by its relatively small sample size (n = 43) and lack of longitudinal data. In some cases, it was further limited with missing variables for some participants. Our results highlight an important link between REM sleep and brain health that has the potential to improve sleep interventions in the elderly; yet, our study sample was highly educated, which may limit the generalizability of our findings to more socio-economically diverse populations. Sleep quantity and quality greatly varies with age and neurodegenerative disease processes . AlthougOverall, our study found that subjective  and objective measures  of sleep quality did not relate to CC FA/MD. Our results, however, do indicate that duration of REM sleep may be a greater contributor to brain white matter integrity than overall sleep quality. It is imperative that future research objectively measures sleep architecture in addition to sleep quality to elucidate the relationship between sleep and brain white matter.S1 Table(DOCX)Click here for additional data file.S2 Table(DOCX)Click here for additional data file.S3 Table(DOCX)Click here for additional data file.


Clofazimine is in widespread use as a key component of drug-resistant TB regimens, but the recommended dose is not evidence based. Pharmacokinetic data from relevant patient populations are needed to inform dose optimization.To determine clofazimine exposure, evaluate covariate effects on variability, and simulate exposures for different dosing strategies in South African TB patients.Clinical and pharmacokinetic data were obtained from participants with pulmonary TB enrolled in two studies with intensive and sparse sampling for up to 6 months. Plasma concentrations were measured by LC-MS/MS and interpreted with non-linear mixed-effects modelling. Body size descriptors and other potential covariates were tested on pharmacokinetic parameters. We simulated different dosing regimens to safely shorten time to average daily concentration above a putative target concentration of 0.25 mg/L.We analysed 1570 clofazimine concentrations from 139 participants; 79 (57%) had drug-resistant TB and 54 (39%) were HIV infected. Clofazimine pharmacokinetics were well characterized by a three-compartment model. Clearance was 11.5 L/h and peripheral volume 10 500 L for a typical participant. Lower plasma exposures were observed in women during the first few months of treatment, explained by higher body fat fraction. Model-based simulations estimated that a loading dose of 200 mg daily for 2 weeks would achieve average daily concentrations above a target efficacy concentration 37 days earlier in a typical TB participant.Clofazimine was widely distributed with a long elimination half-life. Disposition was strongly influenced by body fat content, with potential dosing implications for women with TB. Drug-resistant TB remains a major obstacle to achieving ‘End TB’ targets.,,Clofazimine is recommended by the WHO and the American Thoracic Society for patients with rifampicin-resistant TBA model-based approach that can account for the unusual PK characteristics of clofazimine and predict individual exposures is required to estimate dose–response relationships and inform dose optimization in TB treatment.Clinical and drug concentration data were obtained from a prospective observational cohort study (PROBeX) of adults treated with bedaquiline for pulmonary XDR and pre-XDR TB recruited from three TB hospitals in South Africa. Most participants were treated with regimens that also included clofazimine 100 mg daily, as per local standard of care. Detailed clinical and laboratory data were collected at monthly study visits over 6 months. Sparse PK sampling was performed at roughly 1, 2 and 6 months after starting clofazimine at a single pre-dose timepoint after self-reported dosing. A subgroup of consecutive participants at a single site consented to intensive sampling  at the Month 2 visit. Clofazimine plasma concentrations were measured at the Division of Clinical Pharmacology at the University of Cape Town using a validated LC-MS/MS assay. The lower limit of quantification (LLOQ) was 0.00781 mg/L. The inter-day accuracy ranged from 101% to 105%, and the precision (%CV) ranged from 3.3% to 4.6% during sample analysis.Additional data were obtained from a 14 day Phase 2A early bactericidal activity (EBA) trial of clofazimine alone or in combination with bedaquiline, pretomanid and pyrazinamide.Non-linear mixed-effects modelling was used to analyse clofazimine concentrations from both clinical cohorts simultaneously using NONMEM version 7.4.3,JAC Online).Allometric scaling was applied on all disposition parameters to account for the effect of body size descriptors, including total body weight (TBW), fat-free mass (FFM) and body fat.Using the final model, we simulated time to steady-state for typical body size descriptors of female and male participants observed in our cohort. The final model was also used to simulate different dosing regimens to shorten the time to average daily exposure above a putative target concentration of 0.25 mg/L extrapolated from a murine modelSeventy-nine participants on clofazimine-based regimens with complete 6 month follow-up data were included from the PROBeX observational cohort, in addition to 60 participants from the EBA trial. Overall, median age was 31.0 years (IQR 24.0–39.5), 68 (48%) were female and 54 (39%) were HIV infected. Median weight was 55.1 kg (IQR 48.1–60.9) and percentage body fat was significantly higher in women [median 33.8% (IQR 30.9–37.7) versus 13.9% (IQR 12.0–16.6) in men] Table .n = 139 participants) were included in the analysis: 367 observations from three sampling visits in the PROBeX cohort (including intensive sampling from 22 participants) and 1203 observations from sampling over the 14 day EBA trial. Six samples had concentrations below the LLOQ and were excluded from the analysis. Twenty-five sparse samples from PROBeX participants with poor treatment adherence or missing dosing history had concentrations significantly lower than predicted on visual inspection and were also excluded.Clofazimine concentrations from 1570 plasma samples (p2); FFM for central volume (Vc); and fat mass for volume of distribution in the ‘deep’ compartment (Vp1). The latter parameter resulted in the largest change in objective function value, indicating a significant effect, when included in the model. Age, sex, race, HIV status, duration of treatment and treatment arm were not identified as influential covariates according to stratified visual predictive checks and change in objective function, performed using the final model. The model detected an effect of lopinavir/ritonavir on clofazimine exposure, leading to higher bioavailability; however, the estimate was not sufficiently robust in terms of change in objective function to be included in the final model. Residual unexplained variability was best described by a combined model utilizing both additive and proportional components, with separate additive error estimates for the sparse dataset from PROBeX (due to uncertainty in self-reported dosing times and adherence). A prediction-corrected visual predictive check suggested adequate fit for the pooled data ] was higher at 2 months compared with 14 days, reflecting clofazimine accumulation over time. Estimated plasma exposures were lower in women , resulting from differences in body composition. Consequently, the median time to steady-state , which was 150 days overall, was much shorter for men (105 days versus 230 days for women)  that exceeded those estimated at steady-state, a potential safety concern, particularly for QT prolongation  37 days earlier compared with standard dosing for a typical TB patient in our cohort. For typical male patients, with 13% body fat, the 2 week loading dose achieved a 21 day reduction in time to target concentration. However, female patients, who had an average of 34% body fat, required a longer loading period: a simulation of 4 weeks’ loading led to target attainment 56 days earlier compared with standard dosing in women  and long terminal half-life of ∼30 days, which is consistent with known pharmacological properties of clofazimine.in vitro screeningThe pooled data and observed variance in our cohort were well described by a three-compartment structural model that accounted for the complex multiphase disposition.0–24, Cmax and Cavg), which is in agreement with reported findings from non-compartmental analyses of the EBA trialBody composition explained our key finding of major sex differences in clofazimine plasma exposure. In our combined cohorts, women had a higher proportion of body fat and consequently a larger peripheral volume of clofazimine distribution compared with men. Because PK sampling occurred before steady-state attainment while the drug was still accumulating in peripheral tissues, women from both cohorts had much lower observed clofazimine plasma concentrations and derived exposure parameters  avoid substantially higher predicted Cmax after the loading period than average steady-state peak concentrations to reduce the risk of serious QT prolongation; (ii) achieve shorter time to average daily concentrations exceeding the efficacy target; and (iii) use a simple dosing regimen with once-daily administration. A dosing schedule of 200 mg for 2 or 4 weeks depending on body fat percentage followed by 100 mg daily achieved these objectives and requires further investigation in future clinical trials to delineate the impact on important endpoints and treatment shortening.There is no established clinical PK/PD index for clofazimine efficacy in TB, precluding empirically based dosing simulations. In a murine model, clofazimine was shown to contribute sustained antimycobacterial activity for up to 6 weeks after discontinuation, and this ‘post-antibiotic effect’ was associated with plasma concentrations above 0.25 mg/L;As with all modelling exercises, our analysis has limitations. While the model presented here was able to describe complex data with relatively few parameters, mechanistic assumptions were based on very limited knowledge of clofazimine metabolism and may have limited predictive ability outside the range of observed data.In conclusion, we successfully developed a clofazimine population PK model for South African TB participants, describing massive peripheral distribution volume and prolonged terminal elimination. Clofazimine disposition was strongly influenced by body fat content, resulting in lower plasma exposure among women. The clinical consequences are unknown but clofazimine may require dose individualization at extremes of body composition to optimize use. A 2 week loading dose may support treatment shortening by enabling more rapid attainment of efficacy targets within a safe window of peak concentrations in this population; longer loading periods may be required in patients with high fat mass. This needs to be evaluated in clinical trials. Dose optimization of clofazimine is a research priority in TB, and our model is a necessary first step to understanding concentration–response relationships of this key anti-TB drug.S.W. is supported by the European & Developing Countries Clinical Trials Partnership (grant no. CDF1018), Wellcome Trust (grant no. 203135/Z/16/Z) and National Institutes of Health . J.C.M.B. is supported by the National Institutes of Health . The National Research Foundation provided funding to P.D. (grant no. 109056). M.T.A., P.D. and E.S. were supported by the Swedish Foundation for International Cooperation in Research and Higher Education (STINT) jointly with the South African National Research Council, National Research Foundation (NRF) (NRF grant no. 101575). N.R.G. is supported by the NIH . Gr.M. was supported by the Wellcome Trust (098316 and 203135/Z/16/Z), the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation (NRF) of South Africa (grant no. 64787), NRF incentive funding (UID: 85858) and the South African Medical Research Council through its TB and HIV Collaborating Centres Programme with funds received from the National Department of Health (RFA# SAMRC-RFA-CC: TB/HIV/AIDS-01–2014). The 2 week bactericidal activity study was sponsored by TB Alliance  with support from the Bill and Melinda Gates Foundation, the US Agency for International Development, UK Department for International Development, Irish Aid and Australia Department of Foreign Affairs and Trade.None to declare.JAC Online.Figures dkaa310_supplementary_dataClick here for additional data file.


Surgery for metastatic pancreatic cancer remains controversial as the survival benefit is questionable. The aim of the present study was to analyze the survival of these patients using data extracted from the surveillance, epidemiology, and end results (SEER) program database. Further, studies on resection for metastatic disease to the lung were systematically reviewed. A total of 11,541 cases with synchronous distant metastasis were analyzed. The median survival of single-organ metastasis was better than of multi-organ metastasis . Single organ lung metastasis had longer median survival times compared to the other sites . Resection of the primary tumor was associated with longer survival in synchronous single-organ metastasis to the lung compared to no resection . A systematic literature review identified 79 cases of metachronous lung metastasis with a survival of 120.0 ± 6.32 months and 83.0 ± 24.84 months following resection of the primary tumor and metastasis, respectively. Lower TNM staging, longer interval to metastasis, and single metastatic lesion correlated with better survival. Resection in highly selected pancreatic cancer patients with synchronous and metachronous lung only metastasis might confer a survival benefit and should be considered on an individual basis. It is the fourth leading cause of cancer related deaths in the US, and it is estimated to be the second leading cause in the 2030s2. The majority of the PDAC patients is diagnosed at an advanced stage, and only about 20% of the patients are potential candidates for oncological resection5. Most of the patients die from peritoneal spread or distant metastasis. In consideration of the relevant risk of postoperative complications and the poor survival, it has generally been accepted that for PDAC patients with metastatic disease, resection of the primary tumor or metastatic lesions is contraindicated. However, with the rapid development of new surgical techniques, more precise and minimally invasive operations, and better perioperative care, morbidity and mortality of pancreatic surgery has decreased in experienced centers6. New chemotherapeutic regimens also significantly prolong the survival of PDAC patients with metastatic tumors8. Thus, especially in the context of multimodal therapies, surgery for PDAC patients with metastasis, especially those with oligometastatic and metachronous disease, has gained interest10. Several studies have reported that for selected cases with distant metastasis, resection might relevantly prolong survival, compared to palliative treatment11.Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignant tumors with a rising incidence in both economically developed and developing countriesIn this study, we utilized the surveillance, epidemiology, and end results (SEER) program database and relevant reported clinical studies and case series to comprehensively generate evidence of the impact of surgery for PDAC patients with distant metastasis.A total of 11,541 patients with synchronous distant metastasis with definitive information of the site of metastasis in the liver, lung, bone and/or brain were included. A total of 9372 cases (81.2%) had single organ metastasis, 1911 cases (16.6%) had two organ metastasis, 250 cases (2.2%) had metastasis in three organs and 8 cases had metastasis in all four analyzed organs. Of the 9372 cases of single-organ metastasis, 8222 cases (87.7%) were liver, 941 cases lung (10.1%), 191 cases (2.0%) bone, and 18 cases (0.15%) brain metastasis. In 7156 out of the 9372 cases of synchronous single-organ metastasis, information was available whether the patients were operated/resected or not  of the 11,541 patients was 4.0 ± 0.07 months . The 1-year, 2-year, and 3-year survival rates were 13.9%, 2.6% and 0.6%, respectively Fig. . After mp = 0.015). Well or moderate differentiation predicted better survival compared to poorly/undifferentiated tumors . Lung metastasis had better survival than other metastasis   Table . Tumor l3) Table , older a3) Table , metasta3) Table  and poor3) Table  correlat3) Table .Table 1Up < 0.0001; liver metastasis, 10.0 ± 1.16 months vs 4.0 ± 0.09 months, p < 0.0001) . (ii): metachronous metastasis from unresectable PDAC, with non-surgical treatment (1 study). Kruger et al.12 reported 5 cases with a median survival after diagnosis of metastasis of 10.7 months . (iii): metachronous metastasis after radical resection of the primary tumor, with non-surgical treatment of the metastasis (8 studies); These 8 studies reported on 212 cases. The median survival after initial resection and diagnosis of lung metastasis ranged from 23.0–50.5 months and 7.5–31.3 months, respectively. (iv): metachronous metastasis after resection of the primary tumor, with surgical treatment of the metastasis (17 studies). These 17 studies (including 154 cases) reported a median survival after the initial resection and resection of metastasis of 19.0–92.0 months and 16.0–37.0 months, respectively.Four scenarios of single-organ lung metastasis were initially analyzed Table . (i): syOf those 154 cases from 17 studies, only 79 cases from 11 studies were available with complete survival information for each case and were extracted for further quantitative synthesis Tables  and S3. 14. For pancreatic cancer with metastasis, resection of either the primary tumor or metastasis is generally not indicated; however, for cases with limited (oligo-) metastatic lesions, which could potentially be resected, surgery has been advocated on an individual basis in some experienced pancreatic cancer centers15.Radical resection of both primary and metastatic lesions has been carried for an increasing number of tumor types with promising results18. Obviously, the most important point is to select those patients that might benefit from this aggressive surgical approach17.One reason being that during the last years, more effective chemotherapeutic regimens, such as Folfirinox or gemcitabine plus nab-paclitaxel, have significantly prolonged the survival of metastatic pancreatic cancer patients. In case of initially unresectable cases or limited metastatic spread, these effective therapies have given some patients the chance for resection of the primary tumor or resection of both primary tumor and metastasis21.Although the liver is the most common site of distant metastasis of pancreatic cancer, the lung ranks second. Single-organ metastasis to the lung are not common, but several studies of small cohorts have reported a better prognosis than for other types of metastasis, including distant lymph node metastasis, liver metastasis, and peritoneal metastasis, which indicates that the metastatic site is another important aspect which should be taken into account when considering surgical treatment for metastatic pancreatic cancer patients22. We have also shown that for synchronous single-organ metastasis, older age, worse differentiation, and non-resection of the primary tumor were independent risk factors for worse survival and that survival was better for resected versus non resected synchronous single-organ metastasis to the lung and liver.According to our SEER database analysis, synchronous multi-organ metastasis had worse survival compared to single-organ metastasis, and synchronous single-organ metastasis to the lung had better survival compared to other metastatic sites. This is in line with a recent analysis that also demonstrated better survival for isolated lung metastasis compared to isolated liver metastasisMany factors, such as the general physical status, tumor burden, any additive/palliative chemotherapy/radiotherapy among others, could affect patient survival. Information regarding these items are either absent or incomplete in the SEER database. Importantly, information regarding chemo-/radiotherapy is insufficient and it is therefore officially suggested not to analyze its impact on survival. Together, the extent of selection and treatment bias is difficult to estimate. Obviously, only few patients with synchronous single-organ metastasis to the lung or the liver would benefit from resection. The present study provides some information on how to select potential candidates for resection. For both multi-organ and single-organ metastasis, younger age and better tumor differentiation were independent factors for increased survival in the SEER database analysis.A systematic review of the available clinical reports on resection for metachronous single-organ lung metastasis revealed a striking median survival of 83.0 months (95% CI 34.31–131.69 months) after resection of metastasis. Single metastatic lesions, initial lower TNM staging, and longer interval from primary resection to recurrence were associated with increased survival, although this was not statistically significant.Since resection of pulmonary metastasis can be carried out safely with low morbidity and mortality rates, resection could be considered for those patients with a longer interval between resection of the primary tumor and detection of lung-only metastasis, better differentiated tumor, younger age, and single metastatic lesions.23. Thus, pancreatic cancer with Her-2 amplifications were noted to have less frequent liver metastases and an increased frequency of lung and brain metastasis24. SMAD4 loss was more common in patients with widespread metastatic disease than locally advanced tumors25. Molecular analysis has helped to identify those patients that may benefit from resection of metastasis of colorectal cancer25. In the future, molecular subtyping might also help to identify key signaling pathways and potential surrogates to select metastatic pancreatic cancer patients for whom surgical resection might be beneficial28. Since there are no prospective, randomized trials, solid evidence of criteria for patient selection is lacking.It has been reported that the occurrence of pulmonary metastasis is generally later than that of liver metastasis, and it has also been proposed that the biological behavior of PDAC presenting with a first site of metastasis other than the liver may be related to its molecular phenotypeAlthough this is a comprehensive retrospective study based on the SEER database and a systematic analysis of published reports, there are limitations. (1) Data of systemic treatment of the patients included in the SEER database is incomplete. Therefore, important prognostic factors could not be analyzing in this context. (2) There is a substantial selection bias regarding patients that were resected and those that were not resected in the SEER database. (3) There are no randomized clinical trials and all the published reports were either case series or case reports, and (4) published cases were highly selected, resulting in a significant selection bias.In conclusion, most pancreatic cancer patients with distant metastasis have a poor prognosis. In contrast to other metastatic sites, resection of synchronous and metachronous single-organ lung metastasis shows promising results in terms of safety and survival in highly selected patients. Younger age, better tumor differentiation, longer interval between the initial resection and diagnosis of metastasis, and single metastatic lesions predict better outcome, and all patients should be treated with chemotherapy first. Patient selection is important as expansion of this practice may offer little advantage or even harm patients.Further, it is currently not clear whether there is a true benefit for resection, or whether the data merely reflect a selection bias of patients with a better prognosis independent of resection. Clinical trials or at least multi-center, prospective data are needed to evaluate the outcome of surgical treatment for both synchronous and metachronous single-organ lung metastasis in pancreatic cancer patients.The clinicopathological, surgical and survival information of PDAC patients with distant metastasis were extracted from the SEER database (2010–2014) by using the SEER* Stat 8.3.4 software. The inclusion criteria were as follows: (1) Patients had to be 20 years or older, be pathologically diagnosed with PDAC from January 1, 2010 to December 31, 2014; (2) patient had active follow-up, and did not suffer any other kind of malignant tumor; (3) the information of metastasis in liver, lung, bone, and brain was available. The exclusion criteria were as follows: (1) Patient died from any other cause which was not related to PDAC; (2) metastasis at any other site, besides liver, lung, bone and brain; (3) the information of surgery for the primary tumor or metastatic lesion was missing.The setting of mining strategies of the SEER database was as follows: “cases in research database”, “known age”,“age at diagnosis = 20–85 + ”, “year of diagnosis = 2010–2014”,“site recode ICD-3/WHO 2008 = pancreas”, “malignant behavior”, “diagnostic confirmation = microscopically confirmed”, “ICD-0-3His/behav, malignant = 8140/3 and 8500/3”. Details of the data extraction are presented in Fig. The following variables were extracted: Patient ID, age, sex, year of diagnosis, vital status recode, survival months (>0), COD to site recode, SEER cause-specific death classification, type of follow-up expected, survival months flag, CS mets DX-bone (2010+) (bone metastasis), CS mets at DX-brain (2010+) (lung metastasis), CS mets at DX-liver (2010+) (liver metastasis) and CS mets at DX-lung (2010+) (lung metastasis) and RX Summ–Surg Prim Site (1998+)(surgery for primary site), RX Summ–Scope Reg LN Sur (2003+) (surgery for lymph node) and RX Summ–Surg Oth Reg/Dis (2003+) (surgery for metastatic lesion or the others). All patients were initially diagnosed as stage IV, thus all patients had synchronous metastasis. Since the information of adjuvant treatment is largely incomplete and sometime it could be misleading, it is officially suggested not to analyze the survival impact of adjuvant treatment by using data from SEER database. Therefore, in this study, the information of adjuvant treatment was not analyzed.st, January 1990 and 1st, October 2019) and Science Citation Index Expanded database . The Cochrane Central Register of Controlled Trials (CENTRAL) and ClinicalTrial.org  were also searched to identify randomized controlled trials and non-randomized studies following the Preferred Reporting Items for Systematic reviews and Meta-analysis (PRISMA) guidelines. Both non-randomized  and randomized studies were collected for further analysis. Conference abstracts were excluded.We comprehensively searched the published English literature for cases of PDAC with lung metastasis in the Medline database .Disease specific survival (DSS) was defined as duration from the date of diagnosis to the date of death and recorded as median value ± standard error (SE) with 95% confidence intervals (CI). Survival time was defined as censored if the patients were alive at the last follow-up. The DSS were analyzed by using Kaplan-Meier curves and log-rank tests. Multivariate analysis was performed with a logistic regression model to identify factors predicting survival. All tests were two-tailed and a Supplemental Information.


The efficacy and safety of intravenous thrombolysis (IVT) for acute ischemic stroke with atrial fibrillation (AF) is still controversial.We conducted a meta-analysis of all relevant studies, retrieved through systematic search of PubMed, Embase, and Cochrane databases up to December 31, 2019. Modified Rankin Scale (mRS) scores of 0–1 at 90 days, mRS of 0–2 at 90 days, overall mortality, and incidence of symptomatic intracranial hemorrhage (sICH) were collected as outcome measures. Fixed- and random-effects meta-analytical models were applied, and between-study heterogeneity was assessed.P < 0.001), mRS of 0–2 , as well as significantly higher mortality  and higher incidence of sICH . A comparison of AF patients who were subjected or not to IVT showed that thrombolysis carried a higher risk of sICH  and was not associated with a better prognosis. Subgroup analysis in prospective studies also suggested a poorer functional prognosis and higher mortality in AF patients treated with IVT compared with those who did not receive IVT. Some heterogeneity was present in this meta-analysis.A total of 8509 patients were enrolled in 18 studies. A comparison of IVT treatment in AF versus non-AF patients showed that AF was associated with a significantly lower proportion of patients with mRS of 0–1 (24.1% vs. 34.5%; OR 0.59; 95% CI 0.43–0.81; Acute IS patients with AF had worse outcomes than those without AF after thrombolytic therapy, and had a higher incidence of sICH after thrombolysis than those without thrombolysis. Thrombolysis in ischemic stroke patients with AF should be carefully considered based on clinical factors such as NIHSS score, age, and the type of AF. Atrial fibrillation (AF) is a major risk factor for cardioembolic stroke, which is responsible for up to one-third of all ischemic stroke (IS) cases . AF is aWhat is the efficacy and safety of thrombolysis for acute IS with AF? There are different opinions on this subject. When IS patients with and without AF are compared, most studies indicate that patients without AF show better 90-day functional outcomes after receiving thrombolytic therapy than those with AF –13. HoweWe used PubMed, Embase and Cochrane electronic databases to identify all published studies assessing the efficacy and safety of thrombolytic therapy for acute IS with AF, up to December 31, 2019. The search terms were ((stroke) OR (cerebrovascular disorders) OR  OR (brain infarction)) AND ((tissue plasminogen activator) OR  OR (thrombolytic therapy) OR (thrombolysis)) AND  OR (AFib) OR (AF)). The search did not have any language restrictions.Two investigators (YZ Hu and CM Ji) independently performed the study selection. Studies were considered to be potentially eligible for this meta-analysis if they met the following criteria: (1) they compared the efficacy and safety of thrombolysis in AF versus non-AF patients; (2) they measured the efficacy and safety of IVT in AF patients and compared the outcome with AF patients not treated with IVT; (3) they included sufficient data on the modified Rankin Scale (mRS) 0–1 and mRS 0–2, mortality and the incidence of symptomatic intracranial hemorrhage (sICH). Exclusion criteria were as follows: (1) non-clinical studies, such as reviews, meta-analysis, case reports, letters, or comments; (2) no clinical outcome data.The quality of the cohort studies was assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS) . This scThe potential sources of heterogeneity explored by the mete-regression analysis. The studies’ characteristics were grouped as follows: the type of study design (prospective/ retrospective); stroke severity (NIHSS<16/≥16), thrombolysis time window (<3 h/≥3 h) and the different online year of study. Meta-regression with random effects model was preferred with aggregate-level data.Two investigators (YZ Hu and CM Ji) independently extracted data from the studies , population characteristics .The primary efficacy endpoint was “excellent outcome” , and the secondary efficacy endpoint was “good outcome” . The primary safety endpoint was mortality and the secondary safety endpoint was sICH incidence.I2 test [I2 ranged from 0 to 100%. I2 > 50% indicated high heterogeneity and in these cases the random-effects model was used for meta-analysis. Otherwise, the fixed-effects model was used. A funnel plot and Egger’s test were used to assess publication bias in the meta-analysis. P < 0.05 was considered statistically significant. All statistical tests were performed using STATA software .The proportion of patients with mRS of 0–1 and 0–2, the mortality and the sICH incidence were compared between AF IVT and non-AF IVT groups and (or) AF IVT versus AF non-IVT groups. We calculated the odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for each outcome. The heterogeneity of the studies included in our article was assessed by means of the I2 test . The I2 We identified 1049 potentially relevant studies, but 1024 were excluded after screening the title and abstract. The full texts of the remaining 25 studies were retrieved for detailed evaluation. Based on the search criteria, a total of 18 studies reporting on the efficacy and safety of thrombolysis for acute IS with AF were included in this study   than in patients without AF, and the mortality (P < 0.001) and sICH incidence (P < 0.01) were also higher. On the other hand, in AF IVT versus AF non-IVT prospective studies, the results suggested a poorer functional prognosis (P < 0.01) and higher mortality (P < 0.05) in AF patients treated with thrombolytic therapy than in those who did not receive it, and in retrospective studies, there was a higher sICH incidence in AF IVT patients (P < 0.001).Subgroup analysis was performed according to the study design Table . In both2 was 84.37%  showed there was no significant evidence of publication bias. On the other hand, no significant publication bias was detected based on Begg’s funnel plot . Seven studies compared the outcome in AF patients treated or not with IVT. These studies included 4449 patients, 28.36% of whom received thrombolytic therapy. Five studies included both comparisons. Comparison of AF IVT versus non-AF IVT groups showed that AF was associated with a significantly lower proportion of patients with mRS of 0–1, mRS of 0–2 90 days after stroke and significantly higher mortality and sICH incidence. Comparison of AF IVT versus AF non-IVT groups showed that thrombolysis carried a higher risk of sICH and was not associated with a better prognosis. Subgroup analysis in prospective studies also suggested a poorer functional prognosis and higher mortality in AF patients treated with IVT when compared with those who did not receive IVT.The explanation for the observed results are as follows: First, patients with AF have greater infarct sizes and worse collateral circulation, resulting in worse baseline symptoms , 16. SecI2 was 71.0%. Based on sensitivity analysis, heterogeneity was derived from two studies [I2 = 30.6%; P < 0.001). In addition, the specific type of AF also explained the heterogeneity. Seet et al. reported that patients with chronic AF had worse outcomes than non-AF patients, and was greater in patients with AF of longer duration [Heterogeneity was present in several statistical results of our study. Potential confounders between the groups were not balanced during comparative analysis, which may be a source of heterogeneity. In the included studies, patients with acute IS and AF were generally older and had a higher NIHSS, but we did not adjust for age or NIHSS in the meta-analysis. For example, in the comparative analysis of mRS 0–1 proportions between the AF-IVT and AF non-IVT groups, the  studies , 15. The studies  includedduration . MeanwhiWe acknowledge that our study has several limitations. First, there was only one RCT study (out of 18 studies). Second, sample sizes in most studies were relatively small and varied between groups, which may limit the analytical capacity. Third, in the included studies, the IVT time window was not uniform: in some cases it was less than 3 h, in others less than 4.5 h, and in one case 3–9 h. Fourth, whether intravenous thrombolysis was combined with mechanical thrombectomy was not mentioned in the included studies. Finally, individual data were insufficiently detailed to identify subgroups according to age range, baseline NIHSS score, onset to needle, type of AF and other clinical factors that may influence the efficacy and safety of thrombolysis in AF patients. Further studies with a double-blind design, larger sample sizes and well-matched patient characteristics should be considered.Acute IS patients with AF had worse outcomes than those without AF after thrombolytic therapy as well as a higher incidence of sICH after thrombolysis than those without thrombolysis. Thrombolysis in IS patients with AF should be carefully considered based on clinical factors such as NIHSS score, age, whether patients are taking anticoagulant drugs and type of AF.


Patients and Methods. The study included 40 subjects with chronic diseases and 40 normal subjects of the same age group. Red cell indices, levels of IL-6 and hepcidin, and iron profile were measured in all participants using Bayer ADVIA 120, VITROS 5600, Integrated System/2008, and ELISA assay, respectively.  Anemia of chronic disease (ACD) also termed as the anemia of inflammation has been found to be associated with inflammations, chronic infections, and cancers, particularly in old age. Recent studies revealed that interleukin-6 (IL-6), a proinflammatory cytokine, and hepcidin, an antimicrobial hepatic peptide, play a key role in ACD pathogenesis. p < 0.001). Serum IL-6 and hepcidin levels were substantially higher in the cases than in the controls (p < 0.001). Serum IL-6 and hepcidin levels were substantially higher in the cases than in the controls (p < 0.001). Serum IL-6 and hepcidin levels were substantially higher in the cases than in the controls . Red blood corpuscle (RBC) count, hematocrit (HCT) level, serum iron, mean corpuscular hemoglobin concentration (MCHC), and serum total iron-binding capacity (TIBC) were found to be significantly lower in the cases as compared to controls ( This study detected a significant increase in serum IL-6 and hepcidin levels in patients with ACD than the controls. These findings offer an insight into the role played by both cytokine and peptide in the pathogenesis of ACD and thus provide a rationale for future use of novel drugs inhibiting their effects on iron metabolism. Anemia, which poses a serious health outcome, is a common disorder in elderly people . ApproxiThere are several complicated factors responsible for the development of ACD. Among them, the disturbance in iron homeostasis and iron distribution is the most predominant cause. Enhanced uptake as well as storage of iron occurs within the cells of the reticuloendothelial system, and less iron is released from the mononuclear phagocytic system , 10. In α (TNF-α) and thus induces production of ferritin protein [Multiple studies determined the probable role of interleukins and inflammatory cytokines, particularly interleukin-6 (IL-6) in ACD pathogenesis , 11. IL- protein , 12. Fer protein . Higher β and IL-6 induce hepcidin secretion [Recently, researchers identified a crucial regulatory agent for iron homeostasis  known asecretion . Hepcidiecretion , 17 via ecretion . Ferropoecretion . Hepcidiecretion .Research studies were conducted to develop therapeutic agents inhibiting hepcidin in order to enhance iron utilization from iron storage. Anti-hepcidin antibody was used in mice to validate the efficacy of this agent to inhibit hepcidin . In the The main objective of this study was to assess the role of IL-6 and hepcidin in the development of anemia of chronic disease in Egyptian patients. This will be helpful in the development of novel drugs to inhibit the effect of this inflammatory cytokine and peptide on iron metabolism.This study included 40 subjects diagnosed with ACD . Age of the participants ranged from 60–85 years. There were 14 males and 26 female cases. Forty healthy subjects matched with the age and the sex of the ACD patients were chosen as controls. Both groups were attending the outpatient clinics of Kasr El-Aini Hospital, Faculty of Medicine, Cairo University, Egypt. ACD was described by low hemoglobin (Hb) level and exclusion of other causes of anemia based on clinical and laboratory data. ACD was confirmed by low transferrin saturation, the coexistence of normal or high serum ferritin concentration, and low total iron-binding capacity (TIBC). Patients with other causes of anemia and hypersplenism and those aged below 60 years were excluded.The study was conducted in accordance with the guidelines approved by the Ethics Committee of Kasr EL-Aini Hospital, Cairo University, Egypt. Written informed consent was also obtained from all the study participants.Whole blood samples were collected in EDTA tubes for determining the hematological markers, such as complete blood count, mean corpuscular hemoglobin (MCH), blood film, Hb, and mean corpuscular hemoglobin concentration (MCHC). Hematological analysis was conducted using Bayer ADVIA 120 (Bayer-Germany) . Serum tt-test for independent samples was used to compare different study groups. All data were designated in terms of mean ± standard deviation (SD), median and range, or frequencies (number of cases) and percentages when appropriate. A p value less than 0.05 was considered to be statistically significant for this study. All the statistical calculations were done using the computer program SPSS  release 15 for Microsoft Windows (2006).Student's p < 0.001) than that in the control group (13.2 ± 0.9 g/dl). Moreover, some other hematological parameters were observed to be remarkably lower in cases than in controls (p < 0.001) including RBC counts (3.3 ± 0.7 in cases and 4.4 ± 0.5 in controls), MCHC (31.4 ± 3.3 vs. 35.65 ± 3.28), HCT (26.7 ± 5 vs. 36.1 ± 3.6), serum iron (62 ± 31 vs. 115.9 ± 31), and serum TIBC (171.2 ± 59 vs. 258.6 ± 41). On the contrary, no statistically significant differences were observed for other blood parameters, such as MCV, MCH, and transferrin saturation % .The present study was conducted on 80 subjects: 40 patients and 40 age-matched controls. The characteristics of patients are shown in p < 0.021 and p < 0.001, respectively). A nonsignificant correlation (p > 0.05) was observed between IL-6 and hepcidin among cases.Screening of hepcidin and IL-6 was performed on all subjects, summarized in Anemia of chronic disease occurs due to reduced erythrocyte production associated with chronic inflammatory conditions . ImpaireIn the present study, the hematological parameters, such as RBC, Hb, and MCHC were observed to have significant differences between ACD patients and healthy controls; however, MCV and MCH showed no significant differences between the two groups. Lower Hb and RBC counts in cases than in controls are due to limited availability of circulating iron and reduced erythropoiesis and lower half-life of RBCs , 10. In p < 0.001). The observed finding is analogous to that described in earlier research studies on different populations, which reported strong associations between body iron status, plasma hepcidin levels, and erythropoietin, where higher hepcidin levels were found in subjects with anemia of inflammation [In the current study, a high statistically significant difference has been observed between the cases and controls when the immunological indicators were compared. The serum hepcidin and IL-6 levels showed marked increase in cases than in controls. This was in harmony with the earlier study findings , 26, 27.ammation . All theammation . Higher ammation . Increasammation  althoughα or β induce its production, suggesting that IL-6 and hepcidin possibly led to the development of anemia with age independently [Several previous studies had determined a highly significant correlation between hepcidin and IL-6 levels in ACD patients , 26, 30.endently .Ferruci et al. conducted a study on a large Italian population with ACD and noticed that urinary hepcidin level was not high in subjects with anemia of inflammation compared to nonanemic controls . This waThe present study has few limitations. Firstly, the sample size was not very large and also single centered. Future multi-center studies with large sample size are warranted to infer the existence of a significant link between serum IL-6 and hepcidin levels in ACD patients. Secondly, serum IL-6 and hepcidin were determined at a single time point. Hence, any alteration in their levels, which may appear with time, cannot be considered.The current study has shown the importance of considering the levels of IL-6 and hepcidin along with iron profiles in older patients with chronic diseases to distinguish the difference between true iron deficiency and functional iron deficiency. IL-6 is a key mediator of iron-restricted erythropoiesis leading to ACD. Serum hepcidin levels showed correlation with microinflammation and iron status. Hepcidin is considered to have a central role in maintaining overall iron homeostasis in the body and is a long-sought iron-regulatory hormone. Anemia of inflammation is a complex, multifactorial condition, and its exact pathophysiology is not completely understood, thus making its clinical management quite challenging. Recent research studies on IL-6 and hepcidin led to better understanding of ACD pathogenesis. The knowledge on the mechanism of ACD development obtained from the previous research studies, and the findings of the current study may be beneficial in promoting drug development research focusing on hepcidin or IL-6 antagonists. Inhibition of IL-6 or hepcidin probably would improve the utilization of iron from cellular iron storage sites in ACD. This in turn may result in better outcome of ACD management in older patients. Hence, future studies should be directed in identifying more compounds that are able to bind with either hepcidin or IL-6 and prevent their effect on iron metabolism in ACD patients.


Methionine synthase gene with the susceptibility to prostate cancer (PCa). Nevertheless, the conclusions remain divergent. We performed a systemic analysis with odds ratios (ORs) and 95% confidence intervals (95% CIs) to assess Methionine synthase rs1805087 A/G variant and PCa risk. Furthermore, we utilized in silico analysis to investigate the relationship between Methionine synthase expression and the overall survival (OS) time. Totally, 10,666 PCa patients and 40,750 controls were included. We observed that Methionine synthase rs1805087 A/G variant is associated with an elevated risk of PCa . During stratified analysis, similar results were obtained in Asian populations, hospital-based, high quality studies and that with large sample size. Moreover, in silico analysis indicated the Methionine synthase expression is down-regulated in both young and old PCa subjects (P < 0.05). Compared with the normal subjects, the down-regulated expression of Methionine synthase was found in PCa cases with Gleason score 6 to 9. Our study showed that Methionine synthase rs1805087 A/G variant may be associated with susceptibility of PCa, especially in Asian populations, hospital-based studies and that with high quality and large sample size. Furthermore, Methionine synthase rs1805087 A/G variant may be related to the prognosis of PCa.Previous studies have investigated the association of the rs1805087 A/G variant of  Although the incidence and mortality rate of PCa in Asian populations is lower than that in Western countries2, they have been increasing remarkably in recent years3. In China, the overall incidence is also increasing. PCa has become the most common solid tumor in urban male individuals. Therefore this highlights the need of strategies to prevent advanced PCa5. Up to now, various factors, such as age, hormone exposure and gene mutations, have been proved to be correlated with the development of PCa7. Particularly, growing evidence has indicated that genetic factors may play a crucial role in the etiology of PCa. For instance, the susceptibility of PCa would be increased around two to fivefold in patients suffering from Lynch syndrome. This disease is caused by gene mutations including PMS2 (Postmeiotic segregation increased—2) and MLH1 (Mutl homolog—1)10.Prostate cancer (PCa) remains the most commonly occurring non-cutaneous carcinoma. It can be considered as the leading cause of cancer-related deaths among men in Western countries12. Methionine synthase is located on chromosome 1 (1q43) and with 34 exons. It encodes a core enzyme in folate pathway with 1,265 amino acids (molecular weight 140.5 kDa)13. Methionine synthase rs1805087 A/G variant is the most common mutation. It can lead to an aspartic acid to glycine transition at position 919 of the polypeptide chain16. Previous researches have indicated that this variant is involved in DNA methylation and elevation of homocysteine levels, therefore regulating the enzymatic activity of Methionine synthase17. The association of Methionine synthase rs1805087 A/G variant with susceptibility to PCa was investigated by several studies; however, their conclusions were divergent. In 2009, a systemic analysis evaluated the association between Methionine synthase rs1805087 A/G variant and susceptibility of PCa; nevertheless, they indicated no significant effects of this mutation on PCa risk18. From then on, another research assessed the association between this polymorphism and PCa susceptibility in Han Chinese population. They revealed that Methionine synthase rs1805087 A/G polymorphism was independently associated with PCa by down-regulating the potential of methylation19. The aim of the present study was to explore the association between Methionine synthase rs1805087 A/G variant and PCa susceptibility in larger sample size using multiple analyses to acquire convincing conclusion32.Previous studies have shown that folate metabolizing genes play a central role in carcinogenesis. They are involved in the process of DNA repair and methylationWe conducted a comprehensive literature search according to EMbase, PubMed, Google Scholar, Web of Science, and Chinese SinoMed databases. The keywords are as follows: (MTR OR METH OR methionine synthase) AND (variant OR single nucleotide polymorphism) AND (prostate cancer OR tumor) . In addition, the reference lists of reviews or supplementary material of source documents were also retrieved for further research.Methionine synthase rs1805087 A/G polymorphism; (b) containing adequate information for all genotypes; and (c) case–control studies. Furthermore, studies should be removed if: (a) no control population was included; (b) research focuses on other diseases rather than cancer; (c) repeated previous publications.Studies were enrolled in our analysis according to the following criteria: (a) evaluating the relationship between PCa and Methionine synthase rs1805087 A/G variant. On the other hand, the D-allele is a wild type and considered to be a low-risk allele. Five genetic models were selected in the current study: allelic comparison , homozygote model (GG vs. AA), heterozygote comparison (GA vs. AA), dominant contrast (GG + GA vs. AA), and recessive model (GG vs. GA + AA).Relevant data were independently screened by two of the authors according to the selection criteria. The quality assessment of the included studies was investigated by Newcastle–Ottawa Scale (NOS). The NOS score ranges from 0 to 9 stars. A research can be considered as high-quality if it obtained seven or more stars. The following items were extracted: the first author’s name, publication year, race, source of control, score of NOS, genotype frequency, age range, Hardy–Weinberg Equilibrium (HWE) of cases and controls, sample size, and method. G-allele is a minor allele (mutated gene) for Methionine synthase rs1805087 A/G variant and risk of PCa was assessed by odds ratios (ORs) and 95% confidence intervals (CIs). We adopt Z-test to measure statistical significance of ORs. Assumption of heterogeneity was calculated by Chi-square-based Q-test. Fixed-effect model (Mantel–Haenszel method) was used when P value of Q-test was more than 0.05; otherwise, the random-effect model was used34. Subgroup analyses were conducted by race, sample size of case, quality assessment, and source of controls. P value for HWE was evaluated by web-based program (https://ihg2.helmholtz-muenchen.de/cgibin/hw/hwa1.pl) 35. P value > 0.05 revealed an HWE balance. Sensitivity analysis was adopted to explore the effect of single study on the OR by sequential exclusion of individual study36. I2 value < 50% indicates no statistical heterogeneity among studies. We used the Begg's funnel plot and Egger's test to evaluate the publication bias38. P > 0.05 indicates no statistical significance. All the statistical process was conducted using software STATA v11.0 .The strength of relationship between 42. The written informed consent was required from each participant. The above study protocol has been approved by ethics committee of the Affiliated Changzhou No.2 People's Hospital of Nanjing Medical University and Affiliated Hospital of Jiangnan University. IHS was used to test the Methionine synthase expression in PCa cases enrolled in our centers. We incubated the paraffin section of PRAD in hydrogen peroxide (1%), and then washed it in phosphate buffer saline (PBS). Goat serum was utilized to block binding of non-specific proteins. These sections were incubated with anti Methionine synthase antibody at 1:200. Immunoreactive site was brown using diaminobenzidine. All methods in the present study were conducted in accordance with the relevant guidelines and regulations.Totally, 200 pathologically confirmed PCa patients were enrolled from our centers. Distribution of characteristics of these patients has been listed in our previous studyMethionine synthase in PCa and control counterparts (https://gemini.cancer-pku.cn/) 39. We also used The Cancer Genome Atlas (TCGA) samples to investigate the expression in PCa based on patients’ age, Gleason score, and nodal metastasis status. This database contains expression profiles of 52 PCa subjects and 496 controls . We evaluated the effects of Methionine synthase rs1805087 A/G variant by SNAP tool (https://rostlab.org/services/snap/). String online server was also employed to assess the network of Methionine synthase interaction (https://string-db.org/) 47.We employed the online database to explore the expression of The present study was approved by ethics committee of the Affiliated Changzhou No.2 People's Hospital of Nanjing Medical University and ethics committee of Affiliated Hospital of Jiangnan University.https://www.ncbi.nlm.nih.gov/snp). In Global, G = 0.2118; Europeans, G = 0.1961; Americans, G = 0.1890; Africans, G = 0.2679; East Asians, G = 0.1098; Ashkenazi Jewish, G = 0.1660; and Others, G = 0.2123 , but not in low quality studies  . TGCA database40 showed evidence that the expression of Methionine synthase in PCa cases with Gleason score 6 to 9 was lower than that in normal subjects (P < 0.05, Fig. Methionine synthase expression was both down-regulated in PCa patients with and without lymph node metastasis (P < 0.05, Fig. Methionine synthase rs1805087 A/G variant could impact the protein expression, we used SNAP tool to predict the mutation of Methionine synthase (Fig. Methionine synthase rs1805087 A/G variant is deleterious and effect (Fig. Homo sapiens. The top 10 proteins are: MTRR: Methionine synthase reductase; MTHFR: Methylenetetrahydrofolate reductase; MMADHC: Methylmalonic aciduria and homocystinuria type D protein, mitochondrial; CBSL: Cystathionine beta-synthase-like protein; MMACHC: Methylmalonic aciduria and homocystinuria type C protein; CTH: Cystathionine gamma-lyase; AHCY: Adenosylhomocysteinase; SHMT1: Serine hydroxymethyltransferase; MAT1A: S-adenosylmethionine synthase isoform type-1; MTHFD1: Methylenetetrahydrofolate dehydrogenase (Fig. Methionine synthase expression in PCa tissues, we adopted IHS to assess its expression among PCa participants in our hospitals. Compared with the earlier stage, the down-regulated expression of Methionine synthase was found in more advanced PCa participants (stage >  = T3b versus =  < T2c, P < 0.05, Fig. We employed in silico tool to investigate the expression of P = 0.066; GA vs. AA: t = 2.03, P = 0.064; GG vs. AA: t = 1.95, P = 0.073; GG + GA vs. AA: t = 2.06, P = 0.060; and GG vs. GA + AA model: t = 1.92, P = 0.077.The sensitivity analysis was conducted to investigate the effect of individual study on the OR. As described in Fig. 42. PCa remains one of the most commonly occurring carcinomas among men in Western countries. It has been clarified that several risk factors, such as family history, hormone exposure, lifestyle, may be associated with susceptibility of PCa46. Previous articles showed that Methionine synthase may be involved in the development of PCa29. However, the assoiation between Methionine synthase rs1805087 A/G variant and PCa risk remains ambiguous. For instance, a case–control study based on Iran descendants found that Methionine synthase rs1805087 A/G variant could influence stability and activity of its expression22. This polymorphism might be related to PCa risk in male individuals. However; another researchers did not indicate similar conclusions26. A meta-analysis conducted 10 years ago revealed no significant associations between Methionine synthase rs1805087 A/G variant and PCa risk18. From then on, more and more researchers ascertained their results in different populations26. Hence, in our systemic analysis, all eligible studies based on the inclusion criteria were summerized to ascertain a precise conclusion on the association between Methionine synthase rs1805087 A/G variant and PCa risk. Totally, 10,666 PCa patients and 40,750 controls were included to investigate the Methionine synthase polymorphism.Identification of genetic mutations that related to susceptibility of carcinoma is useful to predict cancer risk and reveal the pathogenesis of various tumorsMethionine synthase rs1805087 A/G variant and susceptibility of PCa under three genetic models. The conclusions acquired from our study were: person carrying the Methionine synthase G-allele may have an increased PCa risk. In stratification analysis by race, we observed similar positive results in Asian populations. Methionine synthase rs1805087 A/G variant might elevate PCa susceptibility as seen in high quality studies, hospital-based studies, and that with large sample size. Furthermore, we used online gene expression mini-database to investigate Methionine synthase expression in PCa and control counterparts. We found that Methionine synthase expression is down-regulated in both young and old PCa subjects. Compared with the normal subjects, the down-regulated expression of Methionine synthase was found in PCa cases with Gleason score 6 to 9, which was consistent with results of our IHS analysis. We also evaluated whether the Methionine synthase expression level influence the PCa patients' OS time. PCa patients with high Methionine synthase expression may have a shorter OS time in the first 5 years. However, with the passage of time, this positive relationship would not be statistically significant. In addition, we used SNAP tool to evaluate the variation of Methionine synthase. The mutation score is 3, which indicate that Methionine synthase rs1805087 A/G variant is deleterious and effect.In our analysis, 15 case–control studies were included. The overall results revealed a positive association between Methionine synthase rs1805087 A/G variant and PCa susceptibility, there are some limitations that should be considered. To start with, only three Asian studies involving Methionine synthase rs1805087 A/G variant and PCa risk were retrieved, which indicates that the total participants count for Asian population remains relatively low for more comprehensive analysis. Second, all included case–control studies were retrospective, which may cause selection bias during the process of analysis. Third, lacking of some original data such as family history, lifestyle, and smoking exposure, may limit the efficacy to further calculate adjusted OR. Fourth, studies with only English or Chinese language were included; therefore, some articles written in other languages may be missing, which may cause some bias in risk estimation. In spite of the limitations, there are several advantages in our analysis. First, HWE is very significant while evaluating genetic variations. P value for HWE is more than 0.05 in most of the included studies, which shows that the conclusion from the included studies is very stable. Second, studies with larger sample size particularly improved the statistical efficiency. Third, we indicated no publication bias while evaluating Methionine synthase rs1805087 A/G variant, so the conclusions of the present analysis are more convincing. As described in Fig. Methionine synthase in Homo sapiens. Nevertheless, there is not enough research on their further mechanism in PCa. Further researches are warranted to explore the interactions in more details.Although considerable resources have been generated to evaluate association between Methionine synthase rs1805087 A/G variant is associated with PCa susceptibility, especially in Asian descendants, hospital-based studies, high quality studies and that with large sample size. Moreover, Methionine synthase rs1805087 A/G variant may be related to the prognosis of PCa. Further studies containing more information such as lifestyle and smoking exposure, are warranted to assess this association in details.Taken together, our study indicated that All the data analyzed in the present study is included in the manuscript.Supplementary file1.