The impact of physical activity on psychotic symptoms: A network analysis


Context: In people with psychotic disorders, the positive role of physical activity (PA) on symptomatology is becoming better understood. In the network approach to psychopathology, mental disorders are conceptualized as complex systems of interconnected symptoms mutually influencing each-other. Therefore, the exact way in which the symptoms and the network structure are influenced by PA remains unknown. Objectives: study the impact of PA on network density, then compare the network structure pre and post intervention. Method: data from a randomized controlled trial is used. 36 men and 25 women (aged 18-55) with a diagnostic of psychotic disorder and obesity participated in a 6-month training program. The Positive and Negative Syndrome Scale (PANSS) assesses symptom severity using semi-structured interviews. 30 items, rated from 1 (absent) to 7 (extreme), cover three dimensions: positive, negative, and psychopathological symptoms. The symptom networks before and after PA are modelized by ggm and stability is re-estimated by Bootstrap, allowing the comparison of density and structure. Results: PA densified the intervention group network. The most influential symptoms are essentially from negative and psychopathological domains. Network structure is different between groups (M=0.48, p = 0.04) as well as connectivity (S = 5.29, p = 0.02). Conclusion: PA seems to ameliorate symptom connectivity compared to control group, providing a first mechanism of action requiring more exploration.