Background/AimsSome observational epidemiologic studies have reported conflicting results on the relationship between hypnotics use and the risk of developing and/or dying from heart disease. We investigated these associations using a meta-analysis of available literatures.MethodsWe searched the databases PubMed and EMBASE, along with the bibliographies of relevant articles to find additional publications in February 2016.ResultsOf 495 articles satisfying our initial criteria, two case-control studies and six cohort studies met our inclusion criteria and were included in the final analyses. Compared with never having used any kind of hypnotics, the odds ratio for overall use was 0.84 for risk of or mortality from heart disease (95% confidence interval, 0.79 to 0.89) in a random-effects meta-analysis of all eight studies. With respect to the geographical region, use of hypnotics was associated with a decreased risk or mortality of heart disease in Asia but not in Western countries. Among various types of sleep medications, zolpidem showed a decreased risk (–29%) of developing or dying from heart disease, but benzodiazepines were related with an increased risk (80%) of or mortality from heart disease.ConclusionsThe current meta-analysis of observational epidemiological studies suggested an evidence of association between hypnotics use and a decreased risk of heart disease.

Background Several studies have suggested that breastfeeding has a positive effect on long-term obesity, diabetes, hypertension, and hyperlipidemia. This study aimed to examine maternal bone health, muscle mass, and obesity based on breastfeeding duration. Methods This study was based on the Korea National Health and Nutrition Examination Survey 2010–2011. We selected 2,027 elderly women by screening survey participants with a history of delivery. Multivariate logistic regression analyses were performed to estimate the odds ratios (ORs) of sarcopenia, osteoporosis, and obesity among four breastfeeding groups. Results The OR of sarcopenia significantly decreased with increasing breastfeeding duration (OR, 0.27; 95% confidence interval [CI], 0.11–0.65; P for trend <0.001), whereas the OR of obesity significantly increased with increasing breastfeeding duration (OR, 2.56; 95% CI, 1.43–4.60; P for trend=0.009) after adjusting for potential confounding variables. We also found a positive correlation between the duration since last delivery and sarcopenia. Conclusion Our results suggest a negative correlation between prolonged breastfeeding and the prevalence of sarcopenia, and a positive correlation between prolonged breastfeeding and the prevalence of obesity. Further studies are needed to clarify the relationship between breastfeeding and sarcopenia in the future.

BackgroundPrevious observational epidemiological studies have shown inconsistent results on the relationship between hypnotics use and risk of cancer. To determine the association between hypnotics use and risk of cancer, we conducted a meta-analysis of available literature.MethodsWe searched databases PubMed, EMBASE, and the bibliographies of relevant articles to locate additional publications in February 2016. Three evaluators independently reviewed and selected eligible studies based on pre-determined selection criteria.ResultsA total of six observational epidemiological studies including three case-control studies and three cohort studies, which involved 1,830,434 participants (202,629 hypnotics users and 1,627,805 non-users), were included in the final analyses. In a random-effects meta-analysis, compared with non-use of hypnotics, the odds ratio for overall hypnotics use was 1.29 for various cancers (95% confidence interval, 1.08–1.53). Subgroup meta-analyses by various factors such as study design, type of case-control study, study region, and methodological quality of study revealed consistent findings.ConclusionOur findings from a meta-analysis of low-biased epidemiological studies suggested evidence linking the use of hypnotics to an increased risk of cancers. The results should be cautiously interpreted because of considerable heterogeneity with a Higgins I2 value.