Executive Functioning as a Predictor of Physical Activity and Treatment-Success of a Lifestyle Intervention for Inpatients in Long-term Psychiatry

Abstract

It has well been established that mortality rates among people with severe mental illness (SMI) are very high compared to the general population. This is often a result from medical conditions such as coronary heart disease. The contribution of sedentary behavior to high mortality rates is receiving increasing attention and has become a target point of lifestyle-interventions in intramural mental healthcare. As emerging evidence shows that engaging in health-behaviors such as physical activity is dependent of self-control mechanisms in the form executive functions, the current study aimed to probe a causal relationship between executive abilities and physical activity in people with SMI. It also aimed to prove that executive functioning predicts the increase in physical activity after participating in a lifestyle intervention. A study was conducted among inpatients (N=54) of long-term mental health care institution ‘Zon en Schild’. Participants were assessed with neuropsychological tests for executive functions. Physical activity (PA) was measured with accelerometers on two separate occasions. The current study failed to demonstrate a predictive role of executive functioning on physical activity for people with SMI. The study was also unsuccessful in supporting the hypothesis that higher levels of executive functioning predict better intervention-outcomes for physical activity. However, Verbal IQ was an unanticipated significant predictor to physical activity. It should be acknowledged that the risk of a type II error is substantial for this study due to power limitations.