Meditation-based mind-body therapies for negative symptoms of schizophrenia: Systematic review of randomized controlled trials and meta-analysis

Meditation-based mind-body therapies (yoga, tai-chi, qi-gong, mindfulness) have been suggested to have a potential therapeutic effect on negative symptoms. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) examining effectiveness of yoga, tai-chi, qi-gong and mindfulness on negative symptoms of schizophrenia, using different databases and trial registries. The primary outcome was effect of mind-body therapies on negative symptoms and the secondary outcome was effect on positive symptoms. Fifteen RCTs were included in the meta-analysis (N = 1081 patients). Overall, we found a beneficial effect of mind-body interventions on negative symptoms at endpoint compared to treatment-as-usual or non-specific control interventions, but the effect was small and moderate to high heterogeneity was present. A subgroup analysis for different types of therapy revealed a significant effect of mindfulness-based and yoga interventions on negative symptoms, but heterogeneity within the yoga subgroup was high. Our results did not show an increase of positive symptoms (N = 1051). Our results suggest a potential for meditation-based mind-body therapies in the treatment of negative symptoms, in particular for mindfulness based approaches and to a lesser extent yoga. Limitations in the available comparisons do not allow concluding on a specific effect of these interventions. Overall, the currently available evidence remains limited and does not yet allow one to recommend mind-body therapies for the reduction of negative symptoms. However, the present findings justify further research on mind-body therapies for the treatment of negative symptoms.