Relationship between objectively measured sedentary behavior and health outcomes in schizophrenia patients: The PsychiActive project.

This study aimed to investigate possible relationships between sedentary behavior and body mass index (BMI), cardiorespiratory fitness (CRF), and health-related quality of life (HRQoL) in schizophrenia patients. Variables contributing to the variability in sedentary behavior were identified. Eighty-two schizophrenia outpatients (mean age±SD: 41.0±8.7years, 87% men, mean illness duration±SD: 17.1±8.9years) wore a multisensor armband for 7 consecutive full days to objectively measure sedentary behavior. BMI, walking capacity (6-minute walking test) as a proxy for CRF estimation and HRQoL (Short Form 36-Item Health Survey questionnaire version 2) were also assessed. Correlation (Pearson or Spearman coefficients) and multiple regression analysis were used. Sedentary behavior was significantly associated with BMI, CRF, and the physical component summary score of HRQoL (r values, -0.34-0.41; all P<0.001) and remained significant after adjustments for age, illness duration, symptom severity, adherence to Mediterranean diet, smoking, and antipsychotic medication (all P<0.05). BMI, CRF and vitality were identified as determinants of sedentary behavior. Consistent relationships between sedentary behavior and BMI, CRF, and the physical component summary score of HRQoL were found in schizophrenia patients. All the identified determinants of sedentary behavior are modifiable and may be important areas for future interventions in this population.