Dongming Wang

Sleep duration and risk of stroke events and stroke mortality: A systematic review and meta-analysis of prospective cohort studies

BACKGROUND Numerous studies have suggested the relationship between sleep duration and risks of stroke mortality and morbidity, however, the effect estimates varied substantially across studies and it remains unknown how many hours of habitual sleep are associated with the lowest risk of stroke outcomes. Therefore, we performed a dose-response meta-analysis of prospective cohort studies to evaluate the relation of sleep duration with risk of total mortality and stroke events. METHODS PubMed and Embase databases were searched through January 2016, and multivariate-adjusted relative risks were pooled by using fixed-effects models. Semiparametric and dose-response methods were used to assess the relationship of sleep duration and risk of stroke and stroke mortality. RESULTS Eleven articles with 16 independent reports were included in our meta-analysis. An approximate J-shaped relationship was detected between sleep duration and risk of stroke and stroke mortality. No evidence of a curve linear relationship was seen between sleep duration and risk of stroke or stroke mortality. Compared with 7-h sleep duration per day, the pooled relative risks for stroke events were 1.07 (95% CI 1.02-1.12) for each 1-h shorter sleep duration among individuals who slept <7h per day and 1.17 (1.14-1.20) for each 1-h increase of sleep duration among individuals with longer sleep duration and the pooled RR for stroke mortality was 1.17 (95% CI 1.13-1.20) per 1-h increase of sleep duration. CONCLUSIONS Both short and long duration of sleep are predictors of stroke outcomes, and long sleep duration is significant marker of stroke mortality.

Sleep duration and risk of coronary heart disease: A systematic review and meta-analysis of prospective cohort studies

BACKGROUND Epidemiological studies suggest an association between sleep duration and risk of coronary heart disease, however, the results are controversial. We conducted this systematic review and meta-analysis to summarize the potential dose-response relationship between sleep duration and risk of coronary heart disease. METHODS The electronic reference databases (PubMed and Embase) were searched through January 2016 with selection criteria for relevant studies. Both semiparametric and parametric methods were used to calculate the pooled risk estimates. RESULTS Seventeen articles with 22 independent reports involving 17,841 incident cases of coronary heart disease among 517,440 participants were included in our meta-analysis. A U-shaped relationship was detected between sleep duration and risk of coronary heart disease, with the lowest risk at 7-8h per day. Compared with 7h sleep duration per day, the combined relative risk of coronary heart disease were 1.11 (95% CI=1.05-1.16) for an reduction of 1h and 1.07 (95% CI=1.00-1.15) for an increment of 1h. And the results almost did not change in the subgroup analysis of gender and fatal cases. Exclusion of any single study did not alter the combined relative risk. In addition, visual inspection of funnel plots, Beggs and Eggers tests failed to identify publication bias. CONCLUSIONS Both short and long sleep durations are significantly associated with increased risk of coronary heart disease. Compared with 7h sleep duration per day, the risk of coronary heart disease increases 11% for an hour decrease and increases 7% for an hour increase.

Tryptophan for the sleeping disorder and mental symptom of new-type drug dependence: A randomized, double-blind, placebo-controlled trial

Introduction: New-type drugs are popular with adolescents and could lead to psychiatry disorders, but no medications have been proven to be effective for these disorders of new-type drug dependence. We aimed to evaluate the efficacy of tryptophan on sleeping disorders and mental symptoms in detoxified individuals with new-type drug dependence. Methods: This randomized, placebo-controlled trial included 80 detoxified individuals with new-type drug dependence, recruited successively from a Compulsory Residential Drug Abstinence Institution in Wuhan, China, from April 2012 to November 2012. Eligible participants were randomly allocated to be treated with tryptophan (1000 mg/d, n = 40) or placebo (n = 40) for 2 weeks. The sleeping disorders and mental symptoms were assessed using Athens Insomnia Scale and Symptom Check-List-90 at baseline and 2 weeks. Results were analyzed according to the “intention-to-treat” approach. Results: Forty-five participants completed the 2-week study, 24 in the tryptophan group and 21 in the placebo group. There were no statistically significant differences in baseline characteristics between groups and the treatment adherence was similar between groups. The reduction in the Athens Insomnia Scale score in the tryptophan group was significantly greater than that in the placebo group (P = 0.017). However, no significant differences were found in Symptom Check-List-90 scores (either by individual dimension or the overall score) between groups (all P > 0.05). The frequency of adverse events was similar and no serious adverse events were reported during the study. Conclusion: Tryptophan was unlikely to be effective for mental symptoms, but could alleviate sleep disorders in short term among detoxified individuals with new-type drug dependence. Future large-scale trials are required to confirm findings from this study.

The cross-sectional and longitudinal effect of hyperlipidemia on knee osteoarthritis: Results from the Dongfeng-Tongji cohort in China

To quantify the cross-sectional and longitudinal effects of hyperlipidemia on knee osteoarthritis (KOA), we studied 13,906 middle-aged or older participants from the Dongfeng-Tongji cohort. Physical examinations were performed at baseline and follow-up. Knee pain was diagnosed by self-reported pain or stiffness. Clinical KOA was diagnosed from knee pain complains and clinical X-ray radiographs. The prevalence of knee pain and clinical KOA was 39.0% and 6.7% at baseline, respectively. Hyperlipidemia was associated with knee pain (OR 1.34, 1.23–1.45) and clinical KOA (1.34, 1.15–1.55). Compared with the participants without hyperlipidemia or use of lipid-lowering drugs, those with hyperlipidemia but no use of lipid-lowering drugs had higher risks of knee pain (1.28, 1.15–1.43) and clinical KOA (1.20, 0.97–1.48), those with hyperlipidemia and use of lipid-lowering drugs had the highest risks of knee pain (1.40, 1.26–1.56) and clinical KOA (1.45, 1.21–1.75). The risks were not elevated among participants without hyperlipidemia but using lipid-lowering drugs for prevention of other diseases. Furthermore, each 1-unit increase in triglyceride was associated with 9% and 5% increases in the risk of clinical KOA prevalence and clinical KOA onset, respectively. In conclusion, hyperlipidemia is associated with elevated risks of knee pain and clinical KOA among middle-aged or older adults.

Association of regular physical activity with total and cause-specific mortality among middle-aged and older Chinese: a prospective cohort study

Association between physical activity and mortality has rarely been investigated among the Chinese population. Furthermore, the most appropriate amount of physical activity for longevity benefits remains unclear. We used data from the Dongfeng-Tongji cohort, including 24,606 middle-aged and older retired adults in 2008 and followed to 2013, to quantify linear and non-linear dose-response relationships between regular physical activity and mortality risks by Cox proportional hazards model. Compared with participants who did not engage in regular physical activity, those performing regular physical activity had significantly 46%, 56%, and 49% decreased risks of mortality from all causes, circulatory, and respiratory diseases, respectively. Each one-SD increase in regular physical activity was associated with 32% decrease of respiratory disease mortality. There were significant nonlinear dose-response associations between regular physical activity and mortality from all causes and circulatory diseases. Mortality risks decreased monotonically with increased regular physical activity amount, and appeared to reach a threshold at around 100 MET-hours/week. More mortality benefits were found among non-smokers than that among current and former smokers. Our results suggest that middle-aged and older Chinese adults can achieve mortality benefits from regular physical activity at the WHO recommended minimum, and the benefit threshold appears at approximately 100 MET hours/week.

The effect of body mass index and physical activity on hypertension among Chinese middle-aged and older population

Few studies have been conducted to explore the independent and combined associations of body mass index (BMI) and physical activity with risk of hypertension in Chinese population. A cross-sectional study of 5291 individuals (aged ≥ 40 years) selected using multi-stage sampling method was conducted from October 2013 to December 2015. In the present analysis, 55.64% of the participants were women, and the mean age of participants was 55.37 ± 10.56. Compared with individuals in normal group, the risks of hypertension were nearly double in overweight subjects (odds ratio [OR] 1.77, 95% confidence interval [CI] 1.53–2.05) and more than three times higher in obese subjects (3.23, 2.62–4.13). Multi-adjusted odds for hypertension associated with low, moderate, and high physical activity were 1.44 (1.17–1.86), 1.40 (1.09–1.79) and 1.000, respectively. In comparison with normal weight subjects who reported high levels of physical activity, subjects who reported both low levels of physical activity and obesity showed the highest risk of hypertension (5.89, 3.90–8.88). In conclusion, both elevated BMI and reduced physical activity appear to play an important role in the risk of hypertension among Chinese middle-aged and older population. The risk of hypertension associated with overweight and obesity can be reduced considerably by increased physical activity levels.

The cross-sectional and longitudinal associations of chromium with dyslipidemia: A prospective cohort study of urban adults in China

Chromium exposure can induce altered lipoprotein metabolism in animals, but the health effects of chromium on dyslipidemia in humans have not been fully evaluated. In this study, we aimed to investigate the cross-sectional and longitudinal effects of urinary chromium on lipid levels and dyslipidemia risk among urban adults from two cities in China. A total of 3762 urban adults from the Wuhan-Zhuhai cohort were included in the initial investigation, and followed up three years later. Urinary chromium concentration was measured at baseline and repeated at follow-up. Associations of urinary chromium concentration with lipid levels and risk of dyslipidemia were analyzed by generalized linear and binary logistic regression models, respectively. We found significant relationships between increased urinary chromium concentration and both reduced triglyceride (TG) level and elevated high-density lipoprotein cholesterol (HDL-C) level at baseline and follow-up. In the cross-sectional analysis, each 1-unit increase in log-transformed urinary chromium was associated with a 0.25 mmol/L decrease in TG and a 0.05 mmol/L increase in HDL-C (P < 0.05); also, downward trends for odds ratios of hyperTG (TG level ≥ 1.7 mmol/L) and hypoHDL-C (HDL-C level < 1.0 mmol/L) were significantly associated with increasing quartiles of urinary chromium (P trend < 0.05). In the longitudinal analysis, each 1-unit increase in log-transformed urinary chromium concentration was associated with a 3% and 6% decrease in the risk of developing hyperTG and hypoHDL-C, respectively (P > 0.05). Our study indicated that significant dose-response relationships between urinary chromium concentration and lipid levels were observed at baseline and at follow-up.

Author Correction: The effect of body mass index and physical activity on hypertension among Chinese middle-aged and older population

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Effects of Shift Work on Knee Pain and Knee Osteoarthritis Among Retired Chinese Workers

Objectives: To evaluate the association between shift work with the risk of knee pain and knee osteoarthritis (KOA), we studied 13,906 retired workers from the Dongfeng-Tongji cohort.

Factors influencing government insurance scheme beneficiary acceptance of the gatekeeper policy: a cross-sectional study in Wuhan, China

BackgroundGatekeeper policy, requiring a patient to visit a primary care provider first, and the patient needs to get his or her primary care provider’s referral before seeing a specialist or going to a hospital, has been implemented in China for about ten years, and it is necessary to assess the patients’ acceptance of gatekeeper policy and to explore the factors influencing patients’ acceptance.MethodsA cross-sectional study with 1162 respondents was conducted between July and September 2015 at four community health centers (CHCs) in Wuhan, China. Face-to-face interview was used to collect information on demographics, acceptance of the gate keeper policy and satisfaction with community health services. Patients’ satisfaction with community health service was evaluated using the European Patients Evaluate General/Family Practice scale and binary logistic regression model was used to examine the factors influencing patients’ acceptance of community health services as gate keepers.ResultsA total of 512 (43.06%) patients accepted gatekeeper policy. Mandatory reimbursement provision (OR: 1.63, 95% CI: 1.23–2.15), patient satisfaction with the aspects of medical care (OR: 1.92, 95% CI: 1.12–3.29) and organization of care (OR: 1.66, 95% CI: 1.05–2.62) were associated with acceptance of gatekeeper policy, after adjusting for potential confounders. Moreover, young people (OR: 0.35, 95%CI: 0.22–0.56) seemed to be more reluctant to accept the policy, when compared with the elder.ConclusionsOur study suggests that mandatory reimbursement provision greatly affects patients’ acceptance of gatekeeper policy, therefore, the policy-maker should pay attention to the negative effect of its mandatory reimbursement provision on patients’ acceptance of the policy. However, improving the aspects of medical care and organization of care will contribute to implementation of gatekeeper policy.