Studies on PA in schizophrenia: What did we learn? What is effective?

Abstract

Schizophrenia is frequently associated with abnormal physical activity (PA) per se (e.g., hypokinesia, motor retardation, etc.) or related to antipsychotic medications (e.g., extrapyramidal symptoms including bradykinesia, tremor, etc.). Daily amounts of PA for subjects diagnosed with schizophrenia tend to decrease over the illness course and contribute to metabolic and cognitive disturbances. PA intervention for schizophrenia patients may result in increased well-being, improved cognitive functioning, fewer negative symptoms and increased self-efficacy, leading to improved management of psychosocial life domains. However, PA trials conducted among people suffering from schizophrenia show several methodological limits: small sample sizes, lack of randomized patients’ allocation, heterogeneity of interventions and inappropriate outcome measures.

Firth et al. (2015) have recently conducted a systematic review and meta-analysis of 11 trials on structured PA in schizophrenia (n = 659, median age of 33 years). The conclusions of this recent review are the following:

– aerobic exercise (for instance exercise bike) of moderate-to-vigorous intensity done at least 90 minutes per week is effective in improving cardiovascular fitness; studies (n = 7) using VO_2max as an assessment of fitness have reported clinically significant increases in VO_2max, “defined as sufficient to reduce cardiovascular disease risk by 15% and mortality by 20%”;

– several low-dose aerobic interventions did not shown any effect;

– there was a “strong effect of exercise on total psychiatric symptoms” (both positive and negative symptoms were reduced);

– total attrition rate was 32%. Group exercise showed a much lower attrition rate than solitary exercise;

– caregivers’ supervision increased compliance as compared to unsupervised intervention;

– in the only study that compared per-protocol and intention-to-treat analysis, a significant improvement in fitness, psychiatric symptoms and overall functioning only occurred in participants who attended > 50% of exercise sessions.

Disclosure of interest

The authors have not supplied their declaration of competing interest.