The experimental group received medium-intensity training for a week. After each training, the experimental group received true stimulation of tPCS (continuous 15 min 1.5 mA current intensity stimulation). The control group received sham stimulation. The physiological and biochemical indicators of participants were tested before and after the experiment, and finally 30 participants in each group were included for data analysis. Results: In the experimental group, creatine kinase (CK), cortisol (C), time-domain heart rate variability indices root mean square of the successive differences (RMSSD), standard deviation of normal R-R intervals (SDNN), and frequency domain indicator low frequency (LF) all increased slowly after the intervention. Among these, CK, C, and SDNN values were significantly lower than those in the control group (p < 0.05). Testosterone (T), T/C, and heart rate variability frequency domain indicator high frequency (HF) in the experimental group decreased slowly after the intervention, and the HF value was significantly lower than that in the control group (p < 0.05). The changes in all of the indicators in the experimental group were smaller than those in the control group. Conclusion: The application of tPCS after medium-intensity training enhanced the adaptability to training and had a significant effect on the maintenance of physiological state. The application of tPCS can significantly promote the recovery of autonomic nervous system function, enhance the regulation of parasympathetic nerves, and delay the occurrence of fatigue.The purpose of this study was to investigate the effect of transcranial pulsed current stimulation (tPCS) on fatigue delay after medium-intensity training. Materials and Methods: Ninety healthy college athletes were randomly divided into an experimental group ( Fatigue often accompanies high-load exercise, and long-term high-load exercise will prolong the elimination time of fatigue, eventually leading to decline in athletic capacity and increased risk of athletic injury ,2. ThereTestosterone (T), cortisol (C), and creatine kinase (CK) in blood are indicators reflecting individual physiological state. Among them, T and C have long been studied as potential biomarkers of catabolic or anabolic state of the body, because they are closely related to the regulation of protein decomposition and synthesis . CreatinAll of the participants signed the informed consent form. The study was carried out in line with the Declaration of Helsinki and was approved by the Institutional Ethics Committee (16 November 2020 (no. 1) by Nantong University).Ninety healthy college athletes were selected as participants and randomly divided into an experimental group and control group. Finally, 30 people in each group  participated in the whole process of the experiment . All of This is a randomized double-blind experiment. Subjects are all from the national standard secondary track and field athletes in Nantong University. They voluntarily participated in this experiment. After screening, 90 subjects were obtained. We divided the subjects into two groups with a ratio of 1:1. Using the scale method in simple randomization, the odd number is the experimental group and the even number is the control group and after multiple assignments, 45 subjects in each group. During the experiment, in order to ensure the concealment of distribution, tPCS was managed by personnel who could operate but did not know the intention and process of this study, and the subjects did not know the grouping and stimulation type.2 electrode was placed in the central supraorbital region of the frontal lobe, and two 5 × 5 cm2 electrodes were placed near the mastoid process of the left and right ear, respectively, and fixed with bandages. During true stimulation, the operator increased the current from 0 mA to 1.5 mA within 30 s. The sham stimulation group received the same stimulation time, stimulation intensity, and current acceleration process, but the current intensity was adjusted to 0 mA 30 s after the initial acceleration. All of the participants were kept quiet during the stimulation to avoid irrelevant stimuli. During the whole process of intervention, if there were adverse reactions (pain or vertigo), the experiment was stopped immediately. At the end of each stimulation, the participants completed a stimulus perception questionnaire to record their feelings.Ninety participants were randomly divided into two groups, with fourty-five participants in each group, and they received true or sham (controls) stimulation of tPCS. In this study, we referred to the research paradigm of Yang et al. on TES stimulation parameters . The stiEach participant underwent venous blood extraction and HRV testing the day before and the morning after the experiment. The day before the experiment, participants were taken by the team leader to the laboratory. Participants rested in the sitting position for 5 min before the experiment. The person in charge of each participant explained the experimental process, purpose, and matters needing attention to the participant, and staff input the basic information of participants and used Firstbeat Sports HRV to collect the signals from participants to ensure synchronization of the HRV index and routine biochemical index. Blood was collected from the left antecubital vein immediately after the HRV test. This procedure was carried out the day before the experiment and after the experiment. RPE test was conducted before formal training, tPCS intervention was conducted immediately after formal training, followed by RPE test. Such operation lasted for 7 days.All of the participants adopted the medium-intensity training standard recommended by the American College of Sports Medicine (heart rate 140–150 beats per minute) . The athBefore the training, the participants were familiar with the RPE scale. The exercise trainer supervised the training and assessed the subjects’ exertion from the RPE scale and heart rate.The subjects began training at 3 p.m. every day. All subjects wore Firstbeat sports to monitor their heart rate and collect their RPE baseline before training. Then, each subject performed warm-up exercises, such as leg pressing exercises, leg kicking exercises, stretching of low back muscles, and then jogging training. After the warm-up action, they conducted a warm-up run of 5 laps exercise, and then started formal training.Physical training was conducted on the first, third, fifth, and seventh days. The arrangement of physical training was as follows: after the auxiliary training, repeat the 4000 m long-distance run 6 times. The six long-distance runs were divided equally into two sections. There was no rest in the first section, but 15 min rest between the two sections. The rest time of the last three long-distance run was 3 min and 5 min, respectively. After the training, the RPE value was recorded again.Technical and tactical training was conducted on the second, fourth, and sixth days. When technical and tactical training was conducted, all auxiliary training was consistent with physical training. Then, the coach asked the subjects to carry out technical and tactical training.Explosive power training: repeat the 400 m training for 10 times, with an interval of 2 min between each training.Then, we did relaxation training.Then, general physical fitness exercises were carried out, such as 40 sit ups, 40 push ups, and 50 m acceleration runs for 3–4 times.Then, leg pressing, kicking exercises, etc.Then, endurance training: repeat the 1500 m training for 7 times, with an interval of 3 min between each training, correct the technical action at the same time, and record the RPE value again after the training.Developed by National Key Technology R&D Program of China, the stimulation current is a bipolar current of 60–80 Hz, the pulse waveform is a square wave, the duty cycle is 29.7%, the stimulation intensity is in the range of 0–2 mA, and the stimulation time is determined by the experimental program. This product passed national security certification on 17 April 2021: report number CHTSM21040049.Related indicators of HRV tested using an HRV tester made in Finland (model: Firstbeat Sports). RR-interval Measurement: BG3 measures beat-by-beat intervals as time between consecutive R-peaks in ECG. Measurement resolution: 1 ms.We used 5 mL EDTA-anticoagulated vacutainer tubes to collect blood samples from the participants, which were produced by Lingen Precision Medical Products (Shanghai) Co., Ltd. .The RPE score was 5–7 in moderate exertion and 8–10 in severe exertion. The reliability of assessment of fatigue degree of the RPE has been verified, and the correlation coefficient between groups is 0.71–0.90 ,27.Physiological state indicators included T, C, T/C, and CK. HRV included time-domain indicators: the standard deviation of normal R-R intervals (SDNN) and root mean square of the successive differences (RMSSD). Frequency domain indicators included high frequency (HF) and low frequency (LF) ,29,30,31In this study, the sample size is based on a two-sided t-test. We set the type I error probability of hypothesis test α is 0.1, and the type II error rate of hypothesis test β is 0.2, considering a 1:1 allocation rate and a drop-out rate of 20%. After calculation and looking up the table, we recruited a total of 114 patients for two groups. Additionally, we found that most of the subjects in similar studies were 30 ,32; therIn this experiment, blood was collected twice, the day before and the day after the experiment. After the subjects reached the blood collection room (the temperature is 20 °C), they sat quietly and rested for 10 min, and then the medical staff took 4 ml of left elbow venous blood and collected the blood sample in a vacuum blank tube to avoid shaking and vibration of the contents (blood).Within 30 min, serum was separated using a high-speed centrifuge . The supernatant was extracted and stored in a medical refrigerator at −80 °C . CK, T, and C were detected using ELISA kits , according to the manufacturer’s instructions, and the whole process was supervised by a principal investigator. All samples were sent to the laboratory for biochemical analysis within 48 h, and all analyses were repeated and performed by trained technicians. Serum samples were analyzed using an automatic biochemical analyzer (RaytoRT-6100 China). Serum CK, T, and C levels were recorded, and the serum T/C ratio was calculated. With abnormal fluctuations, interference, and pseudo-errors were eliminated using Polar software. Five-minute signal samples were selected for HRV time domain and frequency domain analysis.p < 0.05 and the highest significance level was set at p < 0.01.Statistical analysis was carried out using IBM SPSS 22.0  and Microsoft Excel 2019 . The obtained parameters are expressed as mean ± standard deviation. The Shapiro–Wilk test was used to examine the normal distribution of the outcomes. Repeated measures analysis of variance (ANOVA) was used to analyze the effects of each variable (group × measurement time) on each index of function and each index of HRV. Then, post hoc analysis was used if a significance in the interaction was observed and corrected using Bonferroni correction. The significance level was set at In this study, 60 participants completed the entire experimental process. Before the experiment, there were no significant differences between the two groups in the homogeneity test for each physical functional state index . = 14.478077, p < 0.001], T/C , and CK  had the interaction effects of group and measurement time; T , C , T/C , and CK  had significant time main effects  = 7.032, p = 0.010] and HF  had the interaction effect of group and measurement time; RMSSD , SDNN , LF , and HF  had significant time main effects . However, athletes in the experimental group maintained their state due to tPCS intervention, so the change in SDNN was not obvious. This shows that after medium-intensity training, athletes’ function is decreased, the fatigue state appears, and the SDNN index value decreases significantly. The SDNN changed little after tPCS intervention, and there was no significant difference before and after intervention. However, the findings of Zeng et al. [The HRV SDNN indicator mainly reflects the tension in the sympathetic nerve and vagus nerve, which is used to evaluate the overall degree of autonomic nerve damage and recovery. In this study, compared with the experimental group, the SDNN in the control group decreased significantly . Further research by Montenegro found that this change was only seen in professional road cyclists but not in non-athletes, which may be due to higher neural efficiency in the central command of the autonomic nervous system and faster recovery from exercise after tDCS stimulation [Both the sympathetic and parasympathetic nervous systems contribute to the LF power peak (0.04–0.15 Hz). LF reflects overall sympathetic and parasympathetic activity . After tmulation . To a ceThe contribution of parasympathetic nerve activity mainly appears in the HF power peak (0.15–0.40 Hz), and HF mainly reflects parasympathetic nerve activity. Kliszczewicz et al.  found thIn this study, we found that the effect of TES on post-training HRV is complex, and attention should be paid to study participants’ state when explaining motor energy and fatigue state. The participants’ physical state, training intensity, training method, mental state, measuring posture, and measuring time can all affect changes in HRV, which lead to differences in results ,66,67,68Because blood indices were not monitored every day in this experiment, it was impossible to prove whether participants’ cortisol and other blood indices had exceeded their peak or whether these blood indices never reached their peak or even the minimum. Therefore, it was difficult to accurately determine the best time to use tPCS, whether the best effect can be achieved before or during competition. In future research, the frequency of observation of CK, C, and T values can be increased and the best time to use tPCS identified. In addition, there are some individual differences in the application effect of tPCS. The participants in this study were relatively limited. Therefore, more personalized schemes can be explored in the application of tPCS. For different ages and sexes, more accurate intervention programs should be formulated to enhance the intervention effect of tPCS.In the future, this study may be applied to the field to reduce athletes’ sports injuries caused by fatigue. On the other hand, due to the effect of tPCS on cognition, it may alleviate the widespread cognitive fatigue of workers, such as driving for a long time or processing documents. It can even be used in the field of rehabilitation to alleviate the decline in the effect of rehabilitation training caused by fatigue. It is gratifying that some scholars have been doing research in these fields and have achieved certain results ,70. HoweThe application of tPCS after medium-intensity training enhanced the adaptability to training and had a significant effect on the maintenance of the physiological state. The application of tPCS can significantly promote the recovery of autonomic nervous system function, enhance the regulation of parasympathetic nerves, and delay the occurrence of fatigue.


Background: Suicide is a significant public health problem and one of the leading causes of death worldwide. The effect of religion on suicidal behaviors  is an important issue worthy of consideration.Methods: Major electronic databases, including MEDLINE, Web of Science, and Scopus, were searched for the articles published until 26 April 2021. Reference lists were also screened. Observational studies addressing the associations between religion and suicidal behaviors were also examined. Between-study heterogeneity was investigated using the χ2, τ2, and I2 statistics. The probability of publication bias was explored using the Begg and Egger tests, as well as trim-and-fill analysis. The effect size was expressed as odds ratio (OR) with 95% confidence intervals (CIs) using a random-effects model.Results: Out of 11389 identified studies, 63 articles were eligible, involving 8,053,697 participants. There was an inverse association between religion and suicidal ideation OR = 0.83 , suicidal plan OR = 0.93 , suicide attempt OR = 0.84 , and completed suicide OR = 0.31 . There was a no evidence of publication bias.Conclusions: The results of this meta-analysis support the notion that religion can play a protective role against suicidal behaviors. Nonetheless, the effect of religion on suicidal behaviors varies across countries with different religions and cultures. Although this association does not necessarily imply causation, an awareness of the relationship between religion and suicide risk can be of great help in suicide prevention policies and programs. In fact, for every death caused by conflict, five deaths are caused by suicide.4 Based on the World Health Organization (WHO), around one million people die from suicide every year, resulting in a global mortality rate of 16 per 100 000, or one death every 40 seconds.3 These figures understate the problem since they do not include attempted suicides, which are up to 20 times more common than suicide deaths;3 moreover, many people who have suicidal thoughts never seek services.5 Suicide is one of the top 20 leading causes of death and premature mortality in people of all ages across the globe,7 Epidemiological research has demonstrated that several behavioral factors, such as alcohol consumption,8 drug abuse,9 and smoking,10 have a role to play in suicide. Another factor that plays a pivotal role in one’s lifestyle, general health, and wellbeing is religion.11 Based on the Gallup surveys conducted in 114 countries in 2009, religion plays an essential role in the lives of numerous people around the world. About 84% of adults reported that religion was an essential part of their daily lives. In 10 nations and territories, at least 98% of people claimed that religion was significant in their daily lives.12 Another poll conducted by Gallup International in 2012 involving 50 000 people selected from 57 countries across the world in five continents revealed that 59%, 23%, and 13% of participants considered themselves to be religious, non-religious, and convinced atheists, respectively.13 Evidence suggests that there is no known single cause for suicide, rather it is a complicated event influenced by a variety of psychological, social, biological, cultural, and environmental factors.15 So far, the only meta-analysis that assessed the relationship between religion and suicide is the study conducted by Wu et al in 2015.16 They only investigated the association between religion and suicide death. Nonetheless, the relationship between religion and other aspects of suicidal behaviors has not been fully assessed. Furthermore, several epidemiological studies addressing the relationship between religion and suicide have been performed and published on the relationship between religion and suicide since then. In light of the aforementioned issues, this meta-analysis aimed to update the results of the previous one with current evidence and assess the relationship between religion and all aspects of suicidal behaviors, such as suicidal ideations, suicide plans, suicide attempts, and suicide deaths. The relationship between religion and suicidal behaviors was examined by a few review studies.17 The Vice-chancellor of Research and Technology, Hamadan University of Medical Sciences, approved and funded this systematic review. We prepared this report based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement.18 We excluded those studies addressing religiously motivated terrorism and suicidal operations. The exposure of interest was religious beliefs and/or practices, for example, people who manifest devotion to a deity, believe in God or gods, and follow the practices of a religion. We considered people religious regardless of what religion  they believed in and how frequently they attended religious services. The believers were compared with nonbelievers or atheism, and the outcome of interest was suicide. Suicidal behaviors were categorized as suicidal ideation (seriously thinking about committing suicide during the past 12 months or lifetime), suicidal plan (making a plan to commit suicide during the past 12 months or lifetime), suicide attempt , and completed suicide (suicide death). Observational studies  addressing the relationship between religion and suicidal behaviors were included regardless of language, publishing date, nationality, race, age, and gender. The studies that compared suicide rates between different religions or did not discriminate among different types of suicidal behaviors were excluded. The studies investigating the suicidal terrorist attacks were also ruled out. Major electronic databases, including MEDLINE, Web of Science, and Scopus were searched for articles until 26 April 2021 using the keywords:  and . The reference lists of the included papers were screened to identify more eligible studies. The search results were combined using EndNote reference manager software, and duplicate papers of the same study were removed. The titles and abstracts of the papers were screened and ineligible studies were excluded by two authors (JP and FG) independently. Disagreements were resolved by discussion. The full text of the potentially eligible papers was retrieved and examined for further evaluation. The necessary extracted data from relevant studies were imported into an electronic datasheet prepared by Stata software. The following information was extracted: first author’s name, year of publication, country, study population  people), age mean/range, gender, study design , suicidal behaviors , effect estimate , sample size, effect size and its related 95% confidence intervals (CIs).19 Based on this tool, each study is judged on three domains: (a) the selection of the study groups, (b) the comparability of the groups, (c) and the ascertainment of the exposure/outcome of interest. Each item of high quality is given a star. Up to nine stars were assigned to the highest-quality studies. Studies with six or fewer stars were deemed low-quality, while those with seven or more stars were regarded as high-quality. The Newcastle Ottawa Scale (NOS) was used for assessing the quality of the included studies.2 test,20 and its quantity was measured by the I2 statistic.21 Meta-regression analysis was performed to explore the sources of heterogeneity. The following variables were considered potential sources of heterogeneity: six WHO regions , type of population , gender , study design , suicide time , type of belief , adjustment , and quality of the studies . The possibility of publication bias was explored using Egger’s test,22 Begg’s test,23 and the trim-and-fill method.24 Heterogeneity across studies was examined by χ25 The Stata software (version 16) and RevMan (version 5.4.1) were used for data analysis. The relationship between religion and suicidal behaviors was measured using risk ratio (RR) and odds ratio (OR) with their 95% CIs. Wherever reported, we used full adjusted forms of RR and OR controlled for at least one or more potential confounding factors. The data were analyzed at a significance level of 0.05 using the random-effects model.2 ≥ 50%), the sensitivity analysis was performed using the MetaPlot Stata command based on the sequential algorithm.28 When between-study heterogeneity was moderate to high  criteria. Some papers did not separate suicidal ideation from attempted suicide cases, some reported self-harm rather than suicide, some did not report the association numerically, and some others were review articles rather than original articles. Finally, 63 referencesanalysis  involvinanalysis . The studies that addressed the association between religion and various types of suicidal behaviors were as follows: suicidal ideations (37 studies), suicide plan (3 studies), suicide attempt (32 studies), and suicide death (14 studies). The number of studies presented in the forest plots may be more than the total number of included studies since some studies reported the association between religion and different types of suicidal behaviors simultaneously. Due to substantial heterogeneity across the included studies, a meta-regression was performed considering several variables, including WHO regions, type of population, gender, study design, suicide time, type of belief, adjustment, and quality of the studies; nonetheless, neither was statistically significant.P < 0.001). Between-study heterogeneity was high (I2 = 95%). The overall effect became slightly weaker  after performing a sensitivity analysis (P = 0.505) and Egger test (P = 0.130). The association between religion and suicidal ideation is presented in analysis . There wP = 0.200). Between-study heterogeneity was high (I2 = 84%). The overall effect became stronger and significant  after performing a sensitivity analysis (P = 0.602) and Egger test (P = 0.445). The association between religion and suicide plan is displayed in analysis . There wP < 0.001). Between-study heterogeneity was high (I2 = 86%). The overall effect became weaker  after performing a sensitivity analysis (P = 0.347); however, the Egger test did show evidence of publication bias (P = 0.007). However, the trim-and-fill analysis estimated no missing studies. The relationship between religion and suicide attempts is displayed in analysis . The BegP < 0.001). Between-study heterogeneity was high (I2 = 92%). The overall effect became stronger  after performing a sensitivity analysis (P = 0.928) and Egger test (P = 0.177). The association between religion and suicide death is presented in analysis . There w7 Religion is a multi-factorial phenomenon; therefore, we cannot regard risk and protective factors as individual items, rather they should be deemed as a cluster. Diseases are promoted by risk factors while being prevented by protective factors. In this regard, diseases will not develop if risk and protective factors are in balance or if protective factors dominate risk factors.92 Therefore, the role of religion in the prevention of suicide should be considered, along with other influential factors. The results of this meta-analysis pointed to the overall mild-to-moderate protective relationship of religiosity with suicidal ideation, suicide plans, and suicide attempt, as well as a strong protective relationship between religiosity and suicide death. Nevertheless, the observed association between religion and suicidal behaviors does not necessarily imply a direct cause-and-effect relationship. Suicide is a highly complex issue that is associated with a range of risk and protective factors at both individual and contextual levels.93 In addition to sanctioning suicide, participation in organized religions allows members of the congregation and clergies to form an extended support network, which has been demonstrated to be a protective factor against suicidal behaviors.94 Religious belief has also been linked to lower levels of violence and hostility which have constantly been shown to be associated with suicidal behaviors.95 Furthermore, many religions forbid illegal activities, including substance misuse, alcohol consumption, and smoking which have been associated with suicide.10 Therefore, the restriction of high-risk behaviors may have an indirect protective impact against suicide. A vast majority of literature observes a protective effect of religion on suicidal behaviors rather than supports. Several mechanisms have been proposed to explain the protective role of religiosity against suicide. Most religions have strict prohibitions against suicide; therefore, those who are more committed to such religions are less likely to commit suicide. Furthermore, it has been proposed that all major religions discourage all forms of violence, including suicide, and advocate peace and unity which may be deemed life-affirming values, thereby preventing suicide.P value of χ2 and large I2 statistic). The results of the statistical tests used to examine heterogeneity should be interpreted cautiously. The χ2test has low statistical power when the sample size is small or the number of studies is limited. The test, on the other hand, has high power in detecting a modest level of heterogeneity when the sample size or number of the included studies is large.20 Consequently, a portion of the observed heterogeneity can be attributed to the large sample size (involving 8 053 697 participants) and the great number of studies included in the meta-analysis. Nevertheless, inconsistencies across studies can account for a portion of the observed heterogeneity. The observed heterogeneity can be justified on the ground that the results of individual studies come from varied settings with different religions, as well as varying degrees of religious fidelity and adherence to religious teachings. This diversity may be a source of the observed heterogeneity. There was considerable heterogeneity across the included studies  and concluded that religion may play a protective role against suicide in a majority of settings. The results of the referred research were consistent with the findings of the present study. The overall measure produced from OR, estimating the probability of completed suicide, was larger than that obtained from RR, as depicted in 96 Wu et al This meta-analysis is associated with a few limitations and considerations that should be taken into account when interpreting the results. Firstly, the studies included in this meta-analysis, except in a few cases, did not set out to assess the effect of different types of religions, denominations, intensity, and spirituality on suicidal behaviors. Therefore, religion was treated as a binary entity and neither captured this dimensionality nor measured the effect of different aspects of religion on suicidal behaviors. Secondly, the number of studies addressing the association between religion and “suicide plans” was relatively small. This issue reduced the strength of association and the generalizability of the results considering the relationship between religion and suicide plans. Thirdly, we imported the adjusted forms of RR and OR into the meta-analysis wherever feasible. Nevertheless, the confounding effect could not be entirely ruled out since some studies provided crude forms of RR or OR estimates. This problem might lead to an overestimation of the overall effect size of religion. Fourthly, there were eight studies (mainly old studies) that appeared to be eligible for this meta-analysis; nonetheless, their full texts were not available and their corresponding authors did not respond. This issue might raise the possibility of selection bias. Finally, we did not evaluate the religiously motivated suicidal operations and terrorism which is a matter of a completely different nature and has not been the subject of this research. Despite the aforementioned limitations, we developed a wide search strategy to include as many studies as possible, including 56 studies involving 8 053 697 participants. The current meta-analysis was able to examine the association between religiosity and the overall suicide burden. This meta-analysis addressed the association between religiosity and suicide. The results of this study support the notion that religion can play a protective role against suicidal behaviors. Based on current evidence, religious affiliation and participation significantly decreased the risk of suicidal ideation, suicide plans, suicide attempt, and completed suicide. Although this association does not necessarily imply causation, an awareness of the relationship between religion and suicide risk can be of great help in suicide prevention policies and procedures. We would like to appreciate the Vice-Chancellor for Research and Technology of the Hamadan University of Medical Sciences for approval of this study. Jalal Poorolajal contributed to the study conception and design, analysis and interpretation of data, and drafting of the manuscript. Mahmoud Goudarzi contributed to the study design and critical revision. Fatemeh Gohariensaf contributed to the acquisition of data and critical revision. Nahid Darvishi contributed to the study design, acquisition of data, and critical revision. All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work. Not available. The authors declare that they have no conflict of interest. All authors agree with the publication of this manuscript in the current format. There was no human subject in this study. The Vice-Chancellor of Research and Technology, Hamadan University of Medical Sciences funded this study (140006164895). However, the funder had no role in the study design, data collection, and analysis, decision to publish, or manuscript preparation.This meta-analysis revealed the extent to which religion can affect suicidal behaviors . This meta-analysis pointed to the inverse association of religion with suicidal ideation, suicidal plan, suicide attempt, and suicide death. Religion reduced the risk of suicidal ideation, suicidal plan, suicide attempt, and suicide death by 17%, 7%, 16%, and 69%, respectively. The results of this meta-analysis can be of great help in designing suicide prevention policies and programs.


In light of the increased demand for long-term care services in China, there is an ongoing discussion on what factors contribute to older adults’ intended use of long-term care services. This study empirically recruited 239 community-dwelling older adults aged ≥60 years in China and explored factors influencing their intended use of four types of long-term care  based on the Andersen behavioral model . The results showed that older adults were most likely to use psychological care. Age (as the predisposing characteristic) was the significant predictor of the intended use of four types of care. Regarding the intended use of basic life care, the enabling resources of marital status, household composition, income, as well as need factors of preference for the care setting, were influential. Moreover, income and need factors of self-rated physical health status were only two variables associated with the intended use of basic medical care. Concerning the intended use of rehabilitation care, household composition, income, self-rated physical health status, and preference for the care setting were significant predictors. The intended use of psychological care was influenced by enabling resources of marital status, household composition, and need factors of self-rated physical health status, preference for the care setting, and preference for the caregiver. These results can promote the sensitivity of policymakers and caregivers to the community-dwelling older adults’ intended use of long-term care and contribute to the delivery of appropriate care services by public policy. Since the beginning of the 21st century, the aging problem in China has become much more serious. By the end of 2018, the population of older adults aged ≥60 years in China was nearly 250 million, accounting for 17.9% of the total population. This will undoubtedly result in an upsurge in demand for long-term health care services, especially in some urban areas where the number of older adults increases faster. Additionally, the health status decline caused by aging renders the demands of older adults for long-term care services more urgent. By the end of 2018, the disability rate of older adults aged ≥60 years in China reached 11.8%. Moreover, among older adults who are disabled, 25% are entirely unable to take care of themselves [Long-term care involves a broader range of services that can be summarized into four types, namely basic life care, basic medical care, rehabilitation care, and psychological care ,3,4. BasCurrently, long-term care in China is provided for older adults with cognitive or physical impairments. Long-term care services mainly consist of two types: basic life care and basic medical care. By 2020, 426,000 older adults have been reported as long-term care service users . Older aThe use of long-term care for older adults is associated with multiple factors, which are normally integrated by the Andersen behavioral model. This model was initially proposed to describe and explain the intended or actual unitization of health services in the 1960s. According to the model, three domains of factors may influence health service use: predisposing characteristics, enabling resources, and need factors. Predisposing characteristics include people’s basic sociodemographic information, which suggests their biological needs for health services. Enabling resources is concerned with how someone can receive medical services and make use of them. Hence, this involves components such as income and marital status. For need factors, they highlight an individual’s perceived health status and other personal needs that could affect the use of health services . AdoptinIn previous studies, a range of factors that could explain the utilization of health services among older adults have been explored based on the Andersen model. The predisposing characteristics of age, gender, and education level were found to be significant predictors ,13. MoreBased on the previous discussion, this study aims to answer the following questions: (1) What is the situation regarding the Chinese older adults’ intended use of different types of long-term care? (2) How do the factors of the Andersen model predict their intended use? The study examines the hypothesis that older adults’ intended use of different types of long-term care would be significantly influenced by the three domains of factors of the Andersen model. Regarding the two research questions, this study has two purposes. The first is to present and quantify the older adults’ intended use of long-term care. The second is to explore factors that influence the intended use of various types of long-term care services, trying to better understand the relationship between older adults’ intention to use long-term care and their characteristics. Based on these findings, more targeted care services can be provided for improving older adults’ well-being, and long-term care resources can be integrated more successfully.A multistage sampling method was adopted to select 252 participants in Changsha city in China. The first stage involved a random sample of 3 districts from a total of 7 districts in Changsha. In the second stage, 3 streets were randomly selected from each district. In the third stage, 2 communities were randomly selected from each street. In the final stage, 14 older adults will be randomly chosen as participants from each community. The inclusion criteria of participants were as follows: (1) Changsha residents with local households; (2) live in communities; (3) 60 years old or above. Older adults with visual, hearing, language, or cognitive impairments that affect their ability to fill in the questionnaire were excluded from the study.In 2019, a total of 252 questionnaire surveys (including 135 door-to-door interviews and 117 telephone surveys) were performed to collect data from eligible older adults. To help the participants feel at ease, they could freely choose either of the two interview methods and were allowed to be accompanied by their family members (or other people they trusted) when answering the questions. After filtering out invalid questionnaires with incomplete answers, 239 effective surveys were finally obtained. This study was approved by the Research Ethics Committee of Central South University, Changsha. All surveys were conducted with the permission of participants or their legal guardians, and the researcher explained the purpose of the study before moving on to the survey process. Informed consent was obtained from all participants. To ensure confidentiality, identifiers did not appear on any data.Based on the Andersen model, the independent variables of this study were summarized into three domains, as shown in As for the dependent variable, the scale to measure older adults’ intended use of long-term care was developed and validated by the researcher. Older adults were asked how likely they were to use each service. Their answers were rated on a 5-point Likert scale, ranging from very unlikely (1 point) to very likely (5 points), with the larger number representing a stronger intention. The scale contains 20 items that define services of basic life care, basic medical care, rehabilitation care, and psychological care. For these four types of care, which comprised 5, 7, 5, and 3 items, respectively, the sum of possible respective scores are 25, 35, 25, and 15.The scale exhibited good validity and reliability. To ensure content validity, a panel of five experts with experience in nursing older adults was invited to score all items in terms of relevancy by using a 4-point ordinal scale . The content validity index (CVI) for each item was obtained by dividing the number of experts who judged the item as relevant (rating 3 or 4) by the total number of experts. The results indicated that the CVI for each item was >0.8, confirming that the scale had good content validity. Moreover, a principal components analysis was performed, and a stable four-factor solution with 20 existing items was revealed (factor loadings ≥ 0.50). By using Cronbach’s alpha, the internal consistency of the scale was 0.88. A pilot survey was conducted among 50 randomly selected eligible older adults in the Yuelu district of Changsha City, and a second survey was conducted on these older adults two weeks later. The results showed that the test–retest reliability for total scores was 0.89.2) were also performed to compare differences between the participants’ sociodemographic characteristics and their effects on need factors. Paired sample t-tests with composite scores were adopted to compare the use intention of older adults for different care types and services. The composite score of each care type was computed as the sum of corresponding question scores divided by the number of related questions. Hierarchical multiple regression analysis is an appropriate method for comparing the impact of different groups of variables. Hence, this was performed to predict how older adults’ intended use of four types of long-term care was influenced by the three domains of the factors proposed by the Andersen model. In this analysis, categorical independent variables were recoded and converted into dummy variables for regression analysis. The variables of predisposing characteristics were entered in the first block, while the variables of enabling resources and need factors were entered in the second and third blocks, respectively. To carry out the data analysis, SPSS version 25 was employed. In this study, the threshold for statistical significance was p < 0.01, with the consideration that the significance level was supposed to be set as a decreasing function of the sample size [The collected data were used to examine the hypothesis that older adults’ intended use of long-term care was significantly influenced by three domains of factors of the Andersen model. A descriptive statistical analysis was adopted to present the sociodemographic characteristics of the participants and the distribution of demand for each type of long-term care. Chi-square tests (χple size  and corrn = 131). There was no significant difference in gender distribution among participants (p = 0.14). Furthermore, most of the participants were aged 70–79 years  and did not have a bachelor’s degree . There were significant differences in the distribution of age (p < 0.01) and educational backgrounds (p < 0.001). Over 50% of the participants lived with others (such as their spouses and children) and were married. The differences in the distribution of marital status (p = 0.02) and household composition (p = 0.17) were not significant. The participants’ monthly income was concentrated around the levels of 2000–2999 RMB and 3000–3999 RMB. The difference in the distribution of income was significant. Nearly 40% of older adults thought they were in good or fair physical condition, while 67 (28.0%) claimed that they were in poor health. There was no significant difference in the distribution of their self-rated physical health status. Among the 239 participants, 40.6% (n = 97), 20.1% (n = 48), and 39.3% (n = 94) chose the home, the community, and the nursing home as their ideal settings to receive long-term care services, respectively. For caregiver preference, 44.8% (n = 107) believed that family members were ideal caregivers. Meanwhile, 20.7% (n = 49) and 34.5% (n = 83) of the participants preferred to be cared for by a home carer or a healthcare worker, respectively. The differences in the distribution of preference for the care setting and the caregiver were significant (p < 0.001).As shown in 2χ(4) = 66.14, p < 0.001). Specifically, the participants perceived themselves to be in poor physical health as they aged. It was also found that household composition was significantly associated with the preferences for the care setting (2χ(2) =27.67, p < 0.001) and the caregiver (2χ(2) =17.17, p < 0.001). Older adults who lived with others preferred to use care services at home and to be cared for by family members.According to the chi-square tests, there was a significant relationship between age and self-rated physical health status (p < 0.001). By using the same test to compare the intended use of services pertaining to psychological care, the results demonstrated that the intended use of group support was significantly higher than the other two services (p < 0.001).F = 16.62, p < 0.001). Age  was a significant predictor of predisposing characteristics. Moreover, with increasing age, the intended use of basic life care also increased, which is consistent with reality. In Model 2, the addition of the variables of enabling resources resulted in significant changes in R2 of 20%  = 23.53, p < 0.001). In addition, marital status , household composition , and income  were all influential. As displayed in Model 3, preferences for care settings had an impact on older adults’ needs. Specifically, participants who preferred to be cared for in nursing homes  required more services than those who preferred to be cared for at home. Overall, the final model explained 55% of the variance in the intended use of basic life care  = 23.02, p < 0.001).As shown in Model 1 of F = 56.33, p < 0.001). Age  was positively associated with the intended use of basic medical care. In Model 2, the variance in the intended use of basic medical care (explained by the addition of variables of enabling resources) was 4%  = 28.80, p < 0.001). Income  was the only variable of enabling resources that affected the intended use of basic medical care. Regarding Model 3, self-rated physical health status had a significant influence on the intended use of basic medical care. Older adults who described their health as poor  or fair  had a higher intention to use medical services than those who were in good health. Taken together, age, income, and self-rated physical health status explained 50% of the variance in the intended use of basic medical care  = 19.19, p < 0.001).As shown in Model 1 of F = 39.87, p < 0.001). Age  was a significant predictor. Regarding Model 2, the variables of enabling resources significantly additionally explained 12% of the variance in the intended use of rehabilitation care  = 28.35, p < 0.001). Household composition  and income  were positively associated with the intended use of rehabilitation care. In Model 3, self-rated physical health status and preference for the care setting were influential. Older adults who described their health as poor  or fair  displayed a higher intention to use rehabilitation care. Compared with older adults who preferred to be cared for at home, those who preferred to be cared for in nursing homes  required more rehabilitation care services. In summation, the final model revealed five variables that contributed significantly to the intended use of rehabilitation care, accounting for 58% of the variance in those needs  = 26.04, p < 0.001).From Model 1 of F = 16.17, p < 0.001). Moreover, age  had a positive association with the intended use of psychological care. From Model 2, it is evident that the variance in the intended use of psychological care (explained by the addition of the variables of enabling resources) was 12%  = 13.94, p < 0.001). Marital status  and household composition  significantly predicted the intended use of psychological care. Concerning Model 3, the addition of variables of need factors resulted in an improvement in the model, with significant changes in ΔR2 of 18%  = 16.49, p < 0.001). Self-rated physical health status, preference for the care setting, and preference for the caregiver were influential. Participants in poor health  were more likely to need psychological services. Compared with older adults who wanted to be taken care of at home, those who preferred to be cared for in the community  showed lower intention. Finally, older adults who hoped to be cared for by a health care worker  displayed a higher intention to use psychological care than those who preferred to be cared for by family members. As shown in By adopting the Andersen model, the intended use of long-term care and its associated factors were analyzed in Changsha city. The participants in this study were older adults, and more than 50% were male, which is consistent with the population demographics of Changsha city, where males account for 52.3% of the total population . In termAs demonstrated by the hierarchical linear regressions, older adults’ intended use of different types of long-term care was influenced by three domains of the Andersen model. Age was the only significant predictor of predisposing characteristics that had an impact on all types of care. Specifically, older adults’ intended use of long-term care services increased with age, which is consistent with the findings of previous studies ,27. RegaConcerning the intended use of medical care, income was the only influential factor in enabling resources. This finding provided further evidence that poor income can be a hindrance to health seeking and the utilization of care services ,31. HoweConcerning the intended use of rehabilitation care, household composition and income of enabling resources were significant predictors. Moreover, older adults living alone intended more to use rehabilitation care services than those who lived with others, which was corroborated by a prior study indicating that living alone presented difficulties in creating a friendly environment for recovery . PersonaFor the intended use of psychological care, marital status and household composition of enabling resources were identified as significant predictors. Consistent with Pandey’s research , the resThis study also provided new insights. For example, among the four types of long-term care, older adults exhibited the highest intention to use psychological care, while group support was the most needed service within psychological care. Before the 21st century, China’s central government prioritized restructuring the economy because people wanted their material needs to be met. It was not until the reform and opening up, when people’s living conditions improved, that older adults began to realize the importance of psychological well-being. In recent years, although China has gradually paid attention to improving the mental health of older adults, no relevant services have been provided in the long-term care system. In urban areas, psychological care services for older adults are mainly organized by non-governmental organizations (NGOs), such as the Red Cross, social enterprises, and school societies. In other words, the provision of these services is not universal. Some older adults may not have access to receive related services. With the release of the Mental Health Law and the National Mental Health Working Plan, more Chinese older adults may have perceived a need for psychological care. However, the problem of low awareness of mental health issues (and how they should be addressed) remains. According to the surveys conducted in Beijing and Shanghai, only 3.4% of respondents with psychiatric disorders asked for professional help in the previous year . SimilarSeveral strengths emerged in this study. First, numerous determinants were included and analyzed. Furthermore, this is one of the first studies to examine the predictors of the intended use of different types of long-term care in China. In addition, this study adds value to earlier research by introducing older adults’ preferences for the care setting and the caregiver into the need factor, which extends the current research model. However, there were some limitations to this study. First, the data were obtained from a questionnaire survey, and there may be a possibility of ambiguity about the direction of causal influence. Thus, further longitudinal studies should be conducted. Second, the samples for this study were only collected from one city in China, and the results may only reflect specific characteristics of that city. Third, other factors not included in this study  could also be significant predictors of long-term care utilization. Therefore, future studies should include these factors and examine whether they are influential. Furthermore, the relationship between intended use and actual use of long-term care services should receive attention. Exploring the differences between the intended and actual use of long-term care among older adults can provide a basis for service delivery and effective integration of care resources. Notably, geographic characteristics, such as the geographic distance between older adults’ homes and service providers and the distribution of long-term care agencies in communities, can also be considered when exploring the relationship between intended use and actual use of long-term care services.In conclusion, all factors of the Andersen model are important for determining older adults’ intended use of different types of long-term care. Significant predictors that have already been mentioned in previous research  were further confirmed in this study. Moreover, preferences for the care setting and caregiver were also proven to have an impact on the intended use of long-term care. The increasing intention of using psychological care highlights the existing public health problems. Therefore, mindful planning should be proposed to promote the mental health of older adults in China. Some practical implications for health policymakers can be drawn from the findings. First, it is necessary to assess the intended utilization of older adults for long-term care before providing services. In China, Activities of Daily Living (ADL) are currently used as the main basis for providing long-term care services. However, this standard clearly lacks a comprehensive measurement of older adults’ physical and mental status . TherefoSecond, the power of community in caregiving should be valued. According to the results, older adults still rely heavily on family members for long-term care. However, with the successful implementation of the one-child policy and the rapid transformation and changes in society, family security functions are gradually weakening. The “421”  has become the typical family structure in China, which means that older adults have difficulties in relying on the support of family members alone to receive care services . TherefoFinally, it is indispensable to strengthen mental health promotion for older adults. Although the participants in this study had a high intention to use psychological care, related services are not covered by the current long-term care system. Therefore, public health sectors should consider the implementation of policies and programs that facilitate the psychological care and protection of older adults. In addition, the results of some surveys conducted in China have indicated that older people have very limited experiences of dealing with their own mental problems. Therefore, knowledge of mental health issues should be popularized for older adults and their family members to avoid panic caused by emergencies. Moreover, as a social unit based on common geography, interests, and identity, the community plays a role in supporting older adults to maintain their psychological well-being. Community health care workers could help older adults promote social connectedness, and more community infrastructure should be developed to meet mental health care needs among older adults .


Aging is accompanied by changes in the quantity and quality of sleep. Obstructive sleep apnea (OSA) is also more prevalent in the older population. Although severe OSA has been linked to a higher risk of cardiovascular disease regardless of adult age, clinical consequences of mild-to-moderate OSA in the older adults are still uncertain.To investigate the relationships between severity and metabolic, cognitive, and functional characteristics in community-dwelling older adults from a representative sample of the city of São Paulo.In total, 199 participants of the first follow-up of the São Paulo Epidemiologic Sleep Study  >60 years were cross-sectionally assessed through questionnaires, physical evaluations, laboratory tests, and full in-lab polysomnography (PSG). Three groups according to the OSA severity were compared according to sociodemographic characteristics, anthropometric measures, PSG parameters, the frequency of comorbidities, and the use of medications.2) (p = 0.049) and waist circumference (p = 0.005) were significantly higher in the participants with moderate OSA, but not among those with severe OSA. Participants with severe OSA had a higher arousal index (p = 0.007). Multivariate analysis showed that severe OSA was significantly associated with hypertension (p = 0.005), heart diseases (p = 0.025), and the use of two or more medications (p = 0.035).Participants' age ranged from 60 to 87 years with a mean of 70.02 ± 7.31, 59.8% female. In the univariate analysis, body mass index (BMI, kg/mIn a population-based study, severe, but not mild-to-moderate, OSA in older adults was associated with hypertension and the use of more medications. As age advances, anthropometric indicators of obesity may not increase the risk of severe OSA. However, controversies remain whether current severity criteria is associated with higher risks of particularly in older adults , comprising a general population-based sample of São Paulo, Brazil, for this study. Baseline's survey design was comprehensively described elsewhere . In the via questionnaires. Previous clinical history of diseases and medications in use were checked when volunteers came to sleep lab. Participants were instructed to bring their medication lists or boxes to an in-person interview. Medications were checked and grouped according to their categories: cardiac medications, psychoactive medications, hypoglycemiants, and other.Sociodemographic and previous clinical characteristics were assessed All medical conditions and medications used by participants were checked through a personal interview. We considered the number of medications in use and classified according to the body system . Hypertension was considered according to a previous diagnosis; medication check or blood pressure higher than 140 × 90 mm Hg . Diabete2). Circumference measures were part of the anthropometric evaluation, including neck circumference, abdominal circumference, and waist circumference.Height (stadiometer to the nearest 0.1 cm) and weight  were used to calculate the body mass index  using a digital EMBLA system . The exam included electroencephalogram record, electrooculogram record, electromyogram of the submentonian muscles and tibial record, electrocardiogram (ECG) record, oronasal flow record, thoracic and abdominal movement, and record of snoring records, body position, and oximetry. Sleep efficiency was considered decreased when registered as below 85% and the rate of awakening was considered as normal when registered up to 10 events/h. An objective polysomnographic diagnosis of apnea was defined when the AHI was ≥5 obstructive events /hour and the occurrence of periodic leg movements (PLMs) more than 15 events/h (n = 83); group 1 (G1), moderate OSA (n = 56); and group 2 (G2), severe OSA (n = 60).Full in-lab polysomnography (PSG) was performed at the events/h . ParticiZ-score was used for the analysis of the outliers and was used for the variables with no normal distribution. The characteristics of participants were described using means and standard deviations (SDs) or absolute and relative frequency.Assumptions for statistical analysis were assessed by the Kolmogorov–Smirnov test, histograms, and Q–Q plots. The post-hoc of Bonferroni was used. For multivariate regression analysis, the potential predictors for OSA were investigated by the Pearson correlation test and were excluded due to potential multicollinearity. Subsequently, linear regression modeling using enter method was performed. Having evaluated the relationships between the variables, multiple linear regression analysis was then performed to assess inflammatory profiles and comorbidities adjusted by anthropometric variables. For each output (dependent) variable, all the possible combinations of the predictor variables were assessed, with the lowest Akaike information criterion (AIC) used to select the strongest model. The Durbin–Watson (DW) test was used for an autocorrelation, and the variance inflation factor (VIF) and tolerance were performed to determine the presence of multicollinearity. We calculated tolerance and VIF values to evaluate multicollinearity between the variables, with tolerance >0.2 and VIF <10 considered indicative of no collinearity among the independent variables.The p < 0.05 was adopted as the criterion for statistical significance. All the analyses were performed using SPSS statistical software (version 24.0 for Windows).Contrasts were used to test for differences between the levels of a factor. The value of p = 0.007). When stratified by gender, we noted a significant difference in N1 sleep. The percentage was higher in severe OSA. The N3 sleep was lower according to the severity of OSA in both genders . Around 90% of older adults with severe OSA reported taking 2 or more medications, as shown in The use of medications was significantly higher according to OSA, with the highest severity among those classified as severe OSA (G2) (p: 0.01), waist circumference (p: 0.031), hypertension (0.005), and heart problems (p: 0.025) with AHI. Of note, the inclusion of lipid metabolism, total cholesterol, LDL, HDL, and triglycerides did not change the final results.This study evaluated whether the frequently described associations between OSA and clinical comorbidities were present in the sample of older adults from a population-based cohort. Among our findings, severe OSA was not associated with anthropometric indicators of obesity, including BMI and waist circumference. On the other hand, those with severe OSA were more likely to have hypertension and to use two or more medications, as well as to have a higher arousal index. Severe OSA in this aged sample was not associated with other commonly described OSA-related comorbidities, such as diabetes. However, when performing regression analysis considering AHI as a whole, neck and waist circumferences, and waist were significantly with increased AHI.Obesity is characterized as the main risk factor for OSA and is present in approximately 60% of apneic individuals –22. AccoAirway anatomy/collapsibility thus may play a pathogenic role in older adults, whereas a sensitive ventilator control system is a more prominent trait in younger adults with OSA .With regard to cardiovascular consequences of OSA in the elderly, there has been an also controversial finding.Aging by itself is a well-known risk factor for hypertension . Some stA recent meta-analysis, involving 20 original studies demonstrated that OSA increases the risk of hypertension in a dose-response manner . The patMedication use and polypharmacy vary according to the demographic characteristics and tend to increase with age and the presence of comorbidities. The average number of medications used by the older adults ranges from two to five medicines , 38. TheAlthough the literature brings other comorbidities, such as diabetes and depression as associated with the severity of sleep apnea in adults, we did not find this association in our sample , 41. TheA German population-based study investigated the prevalence of OSA in different age and gender groups. The continuous increase of OSA with age challenges the current theory that mortality due to OSA and cardiovascular comorbidities affects the prevalence of OSA at an advanced age . The patObesity is undoubtedly one of the most significant risk factors as it increases the risk by 10–14 times for OSA and weight loss reduces the risk of obesity for this condition . HoweverStudies have reported that the increase in mortality in patients with OSA from cardiovascular causes was only seen in patients under the age of 50 and when the sleep-disordered breathing was severe , whereasTo explain these discrepancies between mortality and sleep apnea in the elderly, Kobayashi et al. proposed that there are two clinically different phenotypes of OSA in the older population: one in which the disease appears in middle age and has more symptoms and consequences; and another in which it appeared in old age and is less serious . Thus, tHowever, a major potential confounder in the association between OSA and mortality is the co-occurrence of comorbidities. Several studies have shown that cardiovascular morbidity and mortality are significantly higher in severe OSA and accompanied by other comorbidities , 55. Whein vitro study in mice subjected to intermittent hypoxia was protected against post-ischemic damage, mediated by HIF-1α  production increases in a gravity-dependent manner and appears to protect the myocardium during periods of severe ischemia with myocardial neovascularization , 59. HypThis study has some limitations. The cross-sectional design does not allow causal inferences. The assessment of medical conditions relied on self-report although all information was reconfirmed as well as all the medicines used throughout an in-person interview. The standardization of hypopneas definition has changed over time, and so has the recent definition adopted by the American Academy of Sleep Medicine. This definition can influence to a greater or lesser degree of the main discretion of OSA severity, which is given by the AHI per hour of sleep . The lacStudies have shown that an estimated 80–90% of people with OSA remain undiagnosed and untreated .Obstructive sleep apnea in the elderly seems not to be a benign condition as it has also been associated with higher healthcare utilization. Systematic surveys, however, that characterize the continuum of disordered breathing during sleep and the associated health impairment in the older population are not yet available , 62.In our study, the association of OSA with hypertension, medication, and a higher arousal index suggests a possible bidirectional association between OSA and comorbidities. These findings emphasize the importance of thorough phenotype evaluation regarding possible gender and age-specific differences in OSA pathogenesis, mechanism, and susceptibility. In a next step, we recommend further investigation of the influence of age and all alterations on the prevalence of OSA. It is becoming more and more important to investigate not only OSA defined purely by the AHI but also OSA syndrome and its symptoms as an apparent disease . TherefoThe original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.The studies involving human participants were reviewed and approved by Ethical Committee of the Federal University of São Paulo. The patients/participants provided their written informed consent to participate in this study.All authors listed have made a substantial, direct, and intellectual contribution to the work and approved it for publication.This work was funded by AFIP (Associação Fundo de Incentivo à Pesquisa) for funding the study and CAPES  PRINT grants number (88887.194874/2018-00).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The participants’ spines were evaluated with Formetric® 4D rasterstereographic analysis at the beginning (BL), in the middle (INT), and at the end (FIN) of the season. Twenty-five parameters were measured in an average 4D modality. The results showed that the intervention factor (BL vs. FIN) had a significant effect on dimple distance (p < 0.05) and on left lateral deviation . Statistical differences were found for the sport typology factor for pelvic antero-retroversion and right lateral deviation. For left lateral deviation, no modulation was found for the sport typology. Asymmetric versus symmetric sport loads showed small statistical differences in a non-professional sample of adult athletes. The practice of asymmetric sports should also be encouraged without exceeding the total number of hours per week.The relation between specific sport practice and possible spine modifications is unclear. The aim of this study was to investigate the effects of different sports on the spine in adult varsity athletes across a six month sports season. Forty-four athletes (24.5 ± 3 years) were divided into two groups according to the typology of the sport practiced: the symmetric sports group (S, 22 athletes: track and field running,  Sports disciplines are commonly divided into symmetric ones like gymnastics and running and asymmetric ones like tennis, fencing, and javelin throwing, despite the lack of a clear categorization ,2,3,4.Although several studies have highlighted this topic, there is still debate on the role that specific sports practices could exert on the postural and musculoskeletal systems.Zaina  stated tMoreover, the relationship between the asymmetric load and possible spine modifications or muscle asymmetry is still not clear, although several studies have been carried out ,13,14,15Regarding spinal loading and sports practice, Wojtys et al.  reportedOther studies suggested that training for different sports can generate significant asymmetry in the trunk muscles’ activation, particularly in the flexors , and thaConversely, Zaina et al.  concludeThus, even if it has been hypothesized that asymmetric load, over several years of practice, could induce chronic modifications on the spine of expert athletes, this argument is not confirmed by the research conducted, which showed sharply contrasting results.Moreover, to our knowledge, no studies have investigated the chronic effects of different sports disciplines on the spine over a period of several months or examined a non-professional population. Our previous study investigated the acute effects of asymmetric load  in two dTherefore, the aim of this study was to evaluate the effects of a 6 month sport practice on the variables related to the dorso-lumbar spine in two groups of varsity athletes, one practicing symmetric sports and the other asymmetric sports.n = 14) and cyclists (n = 8). The second group was formed by 22 subjects practicing an asymmetric discipline .A priori analysis with G*Power indicated that 44 subjects were sufficient to detect a medium effect size (f = 0.25) with a coefficient of correlation of r = 0.5, 95% power, and an α = 0.05 using a within-between subjects design. Therefore, 44 male varsity athletes were recruited from the sport center of the university and were divided into two groups according to the typology of the sport team they belonged to . The fir-Healthy skeletal system;-Eligibility for medical certification for competitive sports;-Age older than 19 years;-Right-handed laterality in order to isolate this variable;-At least 6 years of practice in the respective sport;-A participation in the national university championships.The study inclusion criteria were:-Profiles of elite or high-level athletes from the past or present;-Skeletal or muscular pathologies.Exclusion criteria were:All athletes were monitored during their usual training under the supervision of the university coaches and had a similar lifestyle.The study was a non-interventional/observational study based on the definitions of the European Directive 2001/20/EC, for which the approval of an ethics committee was not requested . However, an Institutional Review Board  has approved the study, which was conducted according to the Declaration of Helsinki and followed the International Code of Ethics for Occupational Health Professionals . All participants gave their written informed consent before participating in the study.Participants underwent three different spine evaluations, respectively, at the beginning, in the middle, and at the end of the academic year, which roughly corresponds to three significant moments in the university sport center schedule plan: the initial evaluation was conducted in November, when the sport center usually ends the initial recruiting selection and training activities start; the intermediate evaluation was conducted in February, after the first half of training sessions; and the final evaluation was conducted in May, when they had concluded the second half of training sessions and before the participation at the national university championships. An assessment was carried out in the morning in laboratory conditions by the same expert operator, who had also followed the manufacturer training course and who conducted all the evaluations for both groups. Subjects were evaluated without shoes and wearing only underwear under the bottom. Subjects were positioned on a hard, flat, even surface, and the position was standardized and kept for the three measurements across the season.Both groups trained with their respective sports teams with an average frequency of three times per week; each single session lasted between one hour and a half and two hours. In order to evaluate the contribution of the different sports disciplines on athletes’ spines, a pre-training meeting was held with the coaches responsible for each sports team. The standardization of the training schedule plan and the modulation of training parameters (volume and intensity) were carried out. As the participants all belonged to the same university sport center, the three different disciplines considered  shared the same periodization and scheduling of the sport season as follows: in the first part of the year, the training program was focused on the general physical preparation and on the sport discipline’s motor skills enhancement (off-season preparation period); in the second part, it was focused on the technical skills’ improvement (pre-competition period); and in the third part, it was focused on the preparation of the competitions (in-season period), i.e., the participation in the national university championships. At the end of each training period, the corresponding spine evaluation was performed, namely baseline (BL), intermediate (INT), and final (FIN), respectively.Athletes’ dorsal and lumbar spines were evaluated using back surface rasterstereographic analysis with the Formetric 4D system , which allows for a tridimensional reconstruction of the dorso-lumbar spine starting from the surface analysis of the back .Previous studies had shown from good to excellent reliability for this device ,25 and gt-test. Thus, analysis of variance (ANOVA) for repeated measurements was applied to compare spine alteration changes (the intervention effect), accounting for sport typology (S vs. A) and intervention (BL vs. INT vs. FIN). Thus, for all variables a 2 × 3 mixed-model analysis of variance (ANOVA) for repeated measures with the between-group factor sport typology (S vs. A) and within-subjects factor intervention (BL vs. INT vs. FIN) was performed. The effect size was also calculated using Cohen’s definition of small, medium, and large effect sizes as partial ƞ2 = 0.01, 0.06, and 0.14, respectively [p ≤ 0.05. The statistical package SPSS  version 24.0 for Windows was used for all statistical analyses.The mean scores and standard deviations (m ± s) for BL, INT, and FIN intervention evaluations were calculated separately for the symmetric (S) and asymmetric (A) groups. Between the groups, differences in the baseline spinal variable scores were verified by means of an unpaired comparison ectively . SignifiThe mean values and SD for BL, INT, and FIN intervention spinal assessments of S and A athletes are shown in p ≤ 0.05), and significant differences were revealed for right lateral deviation and pelvic antero-retroversion. Specifically, for right lateral deviation, mean values and standard deviations at BL were 10.43 ± 5.68 mm and 5.93 ± 3.81 mm (p < 0.01) for the A and S groups, respectively, while for pelvic antero-retroversion, mean values and standard deviations were 20.77 ± 7.60° and 16.27 ± 7.32° (p < 0.05) for the A and S groups, respectively.Differences in the BL spine assessment scores of groups S and A were verified  and on left lateral deviation VPDM . Specifically, athletes significantly increased their dimple distance after intervention  and lateral deviation VPDM (right) . Specifically, athletes of group A showed higher pelvic antero-retroversion values  and higher lateral deviation VPDM (right) values  with respect to athletes of group S.ANOVA revealed a significant main effect of intervention on dimple distance  of adult varsity athletes, respectively practicing symmetric and asymmetric sports, three times across a 6 month season through rastersterographic analysis. The current paper is a natural extension of a previous study conducted by the authors in acute  over a mIndeed, results showed small statistical differences for the factor sport typology for two of the twenty-five parameters measured. Pelvic antero-retroversion and right lateral deviation were found to be higher in the A group, also before intervention, possibly because all the subjects belonging to this group were right-handed and the years of practice could have led to this statistical but not clinical difference; moreover, both parameters are not linked to rotation on the transverse plane as they are, respectively, referred to the sagittal and frontal planes, thus not having incidence on a possible tridimensional spine modification.Furthermore, while the subjects in this study had previously competed in university national championships, and the majority of them had also competed in individual competitions in their respective disciplines, they were not elite or high-level athletes. Therefore, due to the sample characterization, the load induced by the sport discipline may have produced ineffective changes. Thus, it could be argued that asymmetric sports, such as tennis, are not able to induce significant modifications in the main postural parameters if not practiced in a large and professional setting. These results are in line with Zaina et al. , who repp < 0.05) and left lateral deviation . Dimples distance is an invariant parameter, i.e., it is not dependent on the subject’s positioning in relation to the machine; it could be hypothesized that a six month sport season would result in an increase in this parameter in all participants due to the pelvic mass hypertrophy process. With reference to left lateral deviation, no modulation was found for sport typology, but for all athletes, intervention had an increasing effect, suggesting that a deviation on the frontal plane can occur independently by the symmetric/asymmetric load especially in the pre-competition period (INT), which has shown statistical differences in respect to the BL and FIN; in fact, in this period, training is more focused on technical elements that are hypothetically less stressing for the spine, though INT values showed a decrease trend for all participants. However, these two parameters showed statistical variations much lower, respectively, than the between-day smallest detectable changes (SDC) reported by Degenhardt et al. [Instead, referring to the intervention effect, results showed statistical significance for the parameters dimples distance (BL vs. FIN, t et al. .Thus, the present findings support the idea that 6 months of asymmetric/symmetric sport practice do not lead to significant differences in young adult athletes’ spines. It must also be considered that, although not elite or high-level athletes, all subjects involved in the study were healthy and trained students from a physical education university course, thus likely representing an above-average sample.On the other hand, previous research ,32 suggeNonetheless, it has been suggested that double-major adolescent idiopathic curves were more related to physical and sport activities practice, especially gymnastics, than the single-major curve, implying a potential beneficial compensatory effect of sport practice . Indeed,a priori the practice of asymmetrical sports.Therefore, the general finding of the present study, in line with the above-mentioned studies, suggests that therapists and physicians should encourage their patients to regularly and non-intensively practice physical and sport activities to help increase balance, proprioception, and sensorimotor levels without discouraging The present study has some limitations, including the non-elite sport level of the sample, the duration of the observation period, which lasted six months, and the number of evaluations performed, which was limited to three. We did not perform a diagnostic evaluation because of the healthy status of our sample. However, rasterstereography offers a non-invasive, low-cost, and X-ray-free evaluation that has good accuracy and reliability ,31.In line with previous studies, the present findings support the idea that the practice of asymmetric sports does not per se represent a danger for the dorso-lumbar spine of healthy young adults who train for college competitions, especially when this practice does not exceed a weekly amount of 4–5 h. Therefore, and in accordance to the specific existing literature, practitioners and sport educators could play a role in reassuring pupils and their families that it is tendentially safe to practice asymmetric disciplines, albeit not excessively, without negative consequences on musculoskeletal development. However, compensatory and harmonic sport training is advisable to optimize performance and reduce non-contact injuries and stress overloading in general, and especially for asymmetrical sports disciplines.


Owing to the reduced dental treatment infrastructure in the Tanzanian highlands, maintaining good oral health is a challenge for not only the general population but also individual professional groups. In this study, the caries prevalence and, subsequently, the prosthetic treatment needs of the nurses of the Ilembula Lutheran Hospital (ILH) and Ilembula Institute of Health and Allied Sciences (IIHAS), Tanzania, were investigated.One hundred and sixty-eight ILH and IIHAS nurses and nursing students  participated in this cross-sectional study conducted in February 2020. The participants were examined at the dental office of ILH. The Decayed, Missing, and Filled Teeth (DMF/T) Index, Simplified Oral Hygiene Index, and details regarding edentulism, nutrition habits, and socioeconomic factors were collected. Linear regression and binary logistic regression were used for statistical analysis.The mean DMF/T-Index was 6.30 ± 4.52. In 7.14% of the investigated nurses, no dental plaque was detected. An enhanced prosthodontic treatment (Kennedy Class III) demand was identified in 31.50% of the participants, and 4.80% of the participants required treatment for acute malocclusion. Oral hygiene products were used by 99.4% of the patients.The current oral health situation of the study participants showed a moderate restorative and prosthetic treatment demand in the rural area of Tanzania. The development of an interdisciplinary oral health prophylaxis system could be a means to remedy this situation. The most common global diseases associated with social and behavioral factors are dental caries and periodontal disease . CompareSince the trade liberalization of East Africa, there has been an increase in the consumption of refined sugar foods . This haThe aim of the current study is to assess oral hygiene, oral health status, orthodontic and prosthodontic treatment need in nursing staff of the ILH and IIHAS in order to determine if nurses in rural areas without adequate dental treatment facilities could generally screen and educate their patients regarding oral health-related diseases and how to prevent them.A total of 168 adult nurses and nursing students were eligible for participation and all of them  participated in this cross-sectional study. They were a sample of the employees of the IIHAS and ILH, who were available for participating in the oral examinations during their working time and have reached the minimum age of 18 years. Pregnancy was not an exclusion criterion. Data were collected in February 2020. All the participants provided their informed consent before participation.Ilembula is situated in Wanging’ombe District in the Njombe region in the southern highlands of Tanzania. The IIAHS is located at the ILH, which is a Designated District Council Hospital. ILH is a health facility that belongs to the Evangelical Lutheran Church in Tanzania (ELCT)—Southern Diocese (SD) and has operated as a hospital since 1950. The ILH is one of four hospitals of the Iringa-region with a commuter area of up to 2.7 million inhabitants (Morogoro-Mbeya-Region). In 2017, a total of 35.544 patients were treated in the ILH .Data collection was based on standardized case report forms and consisted of a questionnaire and a clinical oral examination according to WHO guidelines. The questionnaire used was structured close-ended. The study supporting administrator was bilingual (Kiswahili and English) and was being held in readiness to clarify any occurring questions regarding to the questionnaire or any other component of the investigation straightforward in the native language of the study participants. The following data were collected using the questionnaire: (1) personal data: age, gender, and nursing specialization (if present); (2) medical and dental history: general diseases, infectious diseases, impairment of wound healing, medication intake, and existing pregnancy (for women); (3) oral homecare: frequency and utensils; (4) luxury foods: frequency and consumption of alcohol, tobacco, coffee, tea, sugar-sweetened beverages, and food; (5) frequency of daily meals.The study included a one-time examination of the oral cavity of the participants. Clinical examinations were carried out by trained and calibrated dentists  in a classroom with natural daylight and a headlight as sources of illumination and with an assistant recording the observations. According to the WHO recommendation for oral health examinations, instrumentation included the following components: dental mouth mirror, dental probe, WHO probe, rubber gloves, and mouthguard. All instruments used were disposable, and they were discarded after each participant’s examination. The following data were collected clinically: the numbers of decayed, missing, and filled teeth were documented according to the decayed, Missing, and Filled Teeth (DMF/T) Index. The WHO definition was used to detect caries. Oral hygiene was measured using the Simplified Oral Hygiene Index (OHI-S) to determine the presence of plaque (debris) and calculus. It was calculated for six tooth surfaces. The buccal surfaces were inspected in teeth 11, 16, 26, and 31, and lingual surfaces in teeth 36 and 46. The categories and corresponding scores of the OHI-S were as follows: good (0.0–1.2), moderate (1.3–3.0), and bad (3.1–6.0). To investigate the malocclusion of the participants, the basic Angle classification was used; that is, sagittal molar occlusion was detected. Additionally, the following intraoral characteristics were described if present: presence of a medial diastema, gingival recession, and dental attrition. The degree of attrition was assessed by the following criteria: No loss of enamel surface characteristics versus loss of enamel surface characteristics. Partial edentulism was described using Kennedy’s classification. The Kennedy classification is a topographic classification that evaluates each jaw separately. Edentulous arches are divided in four major classes . The further subdivision of the major classes I-III is effected according to the number of existing gaps .p value of ≤ 0.05. Due to the explorative nature of the study, p values were interpreted descriptively only.Statistical analysis was performed using the Statistical Package for Social Science . Linear regression was used to analyze the factors associated with DMF/T and OHI-S. In addition, binary logistic regression analysis was performed. Differences were considered significant at a The results with regard to general medical history and dental medical history can be taken from Table The results with regard to dietary history can be taken from Table p = 0.003), gender (p ≤ 0.001), angle class (p ≤ 0.001), frequency of teeth brushing (0.040), and the number of sweets per day (p = 0.013) had a significant influence on the DMF/T (Table p = 0.008), angle class (p = 0.011), and frequency of tooth brushing (p = 0.019) had a significant influence on OHI-S  reported that they did not suffer from general diseases. This could be due to the relatively low median age (22 years) of the participants in this study. Moreover, the entire anamnestic data collection could be causative for the low rate of general diseases. This may be especially true for the prevalence of infectious diseases. Therefore, the prevalence of HIV-positive participants is significantly lower than the average rate of infection in Tanzania (0% vs. 4.8%) . Only 8.The majority of the study participants n = 167) had their own toothbrushes and brushed their teeth using toothpaste n = 153) , 11. In 3 , 11. I7 had theNearly one-third of the participants reported that they had sought dental treatment within the two years prior to study participation . The mosMost study participants (83.3%) had three meals a day . The conThe overall prevalence of caries in the population in this study was 88.7%. This value was significantly higher than other findings of dental caries in Tanzanian adults , 26. HowIn the present study, the observed personal oral hygiene was good, but it was only half as good as the other reported rural areas . PredomiThe orthodontic treatment needs in this study were achievable. The most frequent orthodontic occlusion position was neutral occlusion, followed by distal occlusion, and rarely observed mesial occlusion , 34. HerThe incidence of diastema varies depending on the study region . In the The average tooth loss in the study participants was moderate. However, in nearly two-thirds n = 111) of the participants, at least one tooth was missing, including wisdom teeth. These results are comparable and depend on the relatively young median age of the study participants . Therefo11 of theThe study was limited to the nursing staff of the IIHAS and ILH in Ilembula, Tanzania. There was no randomization of the rural area or the hospital where the study was implemented. Therefore, no significance between the oral health situation of rural or urban regions could be considered. Moreover, it is challenging to transfer the impact of the results of the present study to the oral health situation of the surrounding population because the nursing staff might have different socio-economic backgrounds, levels of education, and availability of medical and dental treatment compared to the average population . NeverthIt can be concluded that most nursing staff of the ILH and IIHAS had good personal oral hygiene and low DMF/T values. The reported recall visits to dental treatment facilities were poor. However, the use of personal oral health items and practice of daily oral hygiene was better than expected. Against the background that the majority of Tanzanian adults mostly seek dental care for pain relief, it is important to sensitize nursing staff in rural areas regarding the prevention of oral diseases. Nurses in rural areas without adequate dental treatment facilities should screen and educate their patients regarding oral health-related diseases and how to prevent them. Therefore, advanced oral health knowledge should be inculcated into the structured education of nursing students. This study should be territorially extended to rural areas in Tanzania due to the lack of similar studies.