RESUMEN
Work-related stress represents a relevant public health issue and solution strategies are mandatory. Yoga is a common approach to manage stress and its effectiveness has been extensively confirmed. Therefore, this study aims systematically to review the effectiveness of Yoga interventions carried out at workplace on work-related stress among employees and to assess their impact quantitatively. Springerlink, MEDLINE, PubMed, CINAHL, Web of Science, Scopus, Cochrane CENTRAL and PEDro databases were searched. Clinical trials comparing workplace Yoga interventions to control groups, and evaluating perceived stress as outcome measure, were assessed for eligibility. All forms and styles of Yoga were considered for the analysis. Out of 3392 initially identified, 6 studies were included in the meta-analysis; 266 participants practicing Yoga interventions at worksite were compared to 221 subjects in control group. Included studies showed "some concerns" about different domains of source of bias. Quantitative analysis showed an overall effect size of -0.67 [95% confidence interval (CI): -0.86, -0.49] in favor of Yoga intervention in reducing stress outcome measures. Hence, workplace Yoga interventions were more effective when compared to no treatment in work-related stress management. Further high-quality studies are needed to improve the validity of these results and to specify more characteristics of the Yoga intervention, such as style, volume, and frequency.
RESUMEN
OBJECTIVE: High selenium status has been associated with adverse cardiometabolic outcomes in selenium-replete populations such as the US. In populations with lower selenium status such as in Italy, there is little epidemiological evidence about the association of selenium with cardiometabolic risk factors. We therefore examined cross-sectional and prospective relationships of serum selenium concentrations with cardiometabolic risk factors including blood pressure, diabetes and blood lipids in the Olivetti Heart Study. METHODS: The study population consisted of 445 adult male individuals for whom baseline serum selenium measurement and cardiometabolic risk factors at baseline (1994-1995) and follow-up examination (2002-2004: average follow-up=8 years) were available. Serum selenium was measured by atomic absorption spectrophotometry. RESULTS: Average serum selenium concentration at baseline was 77.5 ± 18.4 µg/L. In cross-sectional analyses, serum selenium levels were positively associated with serum total cholesterol (p for trend <0.0001) and prevalent diabetes (p for trend <0.05). In prospective analysis, serum selenium at baseline was likewise a strong predictor of serum total cholesterol (p=0.002) and LDL-cholesterol (p=0.001) at follow-up, after adjustment for age, BMI, cigarette smoking, physical activity, and lipid-lowering medication. These associations, however, were no longer significant after additional adjustment for baseline blood lipids. Selenium at baseline did not predict changes in total cholesterol levels between the baseline and follow-up examinations [ß-coefficient (± SE)= 0.09 ± 0.12 (p=0.46)]. CONCLUSION: These findings corroborate previous cross-sectional associations of high selenium status with adverse blood lipid profile and diabetes. However, prospective analyses do not support the causality of these relations. Randomized and experimental evidence is necessary to clarify the mechanisms underlying the observed cross-sectional associations.