Metabolic syndrome, psychological status, and quality of life in obesity. The QUOVADIS Study

Objective: We aimed to investigate the association of the clinical variables of the metabolic syndrome (MS) and psychological parameters on health-related quality of life (HRQL) in obesity. In particular, our aim was to investigate the relative impact of physical symptoms, somatic diseases and psychological distress on both the physical and the mental domains of HRQL. Design: Cross-sectional study Subjects: 1822 obese outpatients seeking treatment in medical centers. Measurements: HRQL was measured by the standardized summary scores for physical (PCS) and mental (MCS) components of the Short Form 36 Health Survey (SF36). Patients were grouped according to tertiles of PCS and MCS. The profiles of individual components of MS and the psychological status in the various tertiles were compared by discriminant analysis. Results: The profile of metabolic and psychological variables was tertile-specific in 62.4% and 68.3% of patients in the lowest and highest tertiles of PCS, respectively, while concordance was low in the mid tertile (32.8%). Concordance was very high in the lowest (74.4%) and in the highest (75.5%) tertile of MCS, and was fair in the mid tertile (53.2%). The main correlates of PCS were obesity-specific and general psychological well-being, BMI, body uneasiness, binge eating, gender and psychiatric distress. Only raised blood pressure and glucose qualified as correlates among the components of MS. The components of MS did not define MCS. Conclusions: Psychological well-being is the most important correlate of HRQL in obesity, both in the physical and in the mental domains, whereas the features of MS correlate only to some extent with the physical domain of HRQL.