Predictors of Health-Related Quality of Life in Indians with Metabolic Syndrome Undergoing Randomized Controlled Trial of Yoga-Based Lifestyle Intervention vs Dietary Intervention

The present study explores the efficacy of 12-week yoga + diet-based lifestyle intervention (YBLI) vs dietary intervention (DI) on health-related quality of life (HRQoL) and identifies the predictors of change in HRQoL in Indians with metabolic syndrome (Met S). Data from the historical randomized controlled trial was used including adults (n = 260, 20-45 years) with Met S. Four domains of HRQoL were measured at baseline, 2 and 12 weeks using WHOQOL-BREF questionnaire. Generalized estimating equation and chi-square test was used to compare 12-week changes in HRQoL domains and proportion of subjects, respectively. Changes in HRQoL were predicted using regression models concerning changes in body mass index (BMI), physical activity, total calorie intake, adiponectin, and superoxide dismutase (SOD) levels. Exploratory mediation analysis was carried out using Baron & Kenny approach. YBLI resulted in a significantly greater increase in the physical domain score of HRQoL than DI. A significantly greater proportion of subjects in YBLI group (71%) showed an increase in physical domain scores compared to DI (51%). A unit change in BMI negatively predicted a unit change in physical, psychological and environmental health. Whereas, a unit change in adiponectin and SOD levels positively predicted a unit change in physical and environmental health. Partial mediation between YBLI intervention and physical HRQoL domain was observed via adiponectin. In conclusion, a 12-week YBLI has a positive and greater effect on HRQoL physical domain score than following DI alone. Changes in BMI, adiponectin, and SOD levels may predict changes in HRQoL domains after lifestyle intervention.