Health-related quality of life and aerobic fitness in people with schizophrenia

The purpose of this cross-sectional study was to investigate whether aerobic fitness contributes to the health-related quality of life (HRQoL) in people with schizophrenia, while adjusting for other previously-established contributory factors. Thirty-four male (34.1 +/- 12.0 years) and 13 female (34.3 +/- 9.2 years) participants performed a submaximal Astrand-Rhyming cycle ergometer test and completed the 36-item Short-Form Health Survey, the International Physical Activity Questionnaire, and the Psychosis Evaluation tool for Common Use by Caregivers. After controlling for age and sex, illness duration (12.4 +/- 11.2 years, r(2)=0.38, P<0.001), fewer positive (9.3 +/- 4.3, r(2)=0.30, P=0.006) and cognitive (8.4 +/- 3.8, r(2)=0.28, P=0.011) symptoms, and higher aerobic fitness (34.5 +/- 8.7ml O(2)min(-1)kg(-1), r(2)=0.36, P=0.001) were found to be independent significant predictors of physical HRQoL (mean score 66.6 +/- 18.5). However, when all variables were included in the same regression model, only illness duration (P=0.004) and positive symptoms (P=0.045) remained significant predictors, while there was a trend (P<0.10) for age and aerobic fitness. The final model explained 54% of the variability in physical HRQoL. No significant correlates for mental HRQoL (54.9 +/- 18.5) were found. People with schizophrenia might improve their physical HRQoL by improving their aerobic fitness. Mental health nurses should assist in facilitating improvements in aerobic fitness through facilitating physical activity participation in patients with schizophrenia.