The impacts of aerobic exercise and mind-body exercise (yoga) on neuro-cognition and clinical symptoms in early psychosis : a single-blind randomized controlled clinical trial

Abstract

Motivation Impairments of attention and memory are detectable in early psychosis, and often result in severe, longstanding functional impairments. Pharmacological interventions for cognitive impairments have been largely unsuccessful. The current study aims to explore the effects of aerobic exercise and mind-body exercise (yoga) on cognitive functioning and clinical symptoms in female patients with early psychosis. The potential neuromechanism underlying the clinical consequences was also investigated.

Methods Female patients (n=120) diagnosed with schizophrenia spectrum disorders, brief psychosis, psychosis NOS, or delusional disorder (according to SCID) were recruited from three hospital/clinic sites. They were randomized into integrated yoga therapy group, aerobic exercise programme group, and waiting list as the control group. Both interventions were held three times weekly. At baseline and at 12 weeks, clinical symptoms, cognitive functions, quality of life and fitness levels were assessed in all participants, and completed structural MRI data were collected in 58 patients. Repeated measures ANOVA and ANCOVA analyses of the clinical, cognitive, quality of life and fitness data were compared between baseline and at 12 weeks among the three groups. Post-hoc Bonferroni test was used for comparing between two groups. Structural MRI data was analyzed by FreeSurfer V5.1 and Qdec V1.4 to calculate the brain volume and cortical thickness.

Results Completed clinical and cognitive data were collected in 85 patients, and completed MRI imaging data of good quality were collected in 39 patients. No significant differences in age, education years, and duration of the illness at baseline were observed among the three groups. Both yoga and aerobic exercise groups demonstrated significant improvements in verbal encoding (p<0.01), short-term memory (p<0.05), long-term memory (p<0.01), and working memory (p<0.01) with moderate to large effect sizes compared to control groups. The yoga group showed significantly enhanced attention and concentration (p<0.05). Both yoga and aerobic exercise significantly improved overall clinical symptoms (p<0.05) and depressive symptoms (p<0.05) after 12 weeks. Significant increases were observed in the thickness of the left superior frontal gyrus and the right inferior frontal gyrus (pars triangularis) in the aerobic exercise group. Significant increases were observed in the volume of the postcentral gyrus and the posterior corpus callosum in the yoga group. There was a statistically significant correlation between improvements in working memory and changes in the postcentral gyrus (r=0.54, p<0.01) after controlling for the multiple comparisons with a Bonferroni adjusted alpha level.

Discussion Both types of exercise improved memory in early psychosis patients, with yoga having a superior effect on attention than aerobic exercise. Observed increments in the cortical thicknesses and volume may indicate improved neurogenesis.

Significance There have been few systematic clinical trial studying exercise and psychosis, and none of them has explored the effects of exercise in female patients with early stage psychosis. The present study indicates possible interventions for cognitive impairments in the patients with early psychosis, which are non-invasive and mostly safe. The application of yoga and aerobic exercise as adjunct treatments to treat psychosis in the clinical setting should be advocated.