To explore the efficacy of aerobic exercise (AE) on the cognitive function in patients with schizophrenia using meta-analysis.

A systematic online search was performed for eligible randomized controlled trials using the electronic databases of PubMed, EMBASE, Cochrane Library, China national knowledge infrastructure (CNKI), Wanfang data (Wanfang), VIP, China biology medicine disc (CBMdisc), and Google Scholar. The search was performed from database inception until September 14, 2020. The essential demographic characteristics, intervention programs, outcome indicators, and the average change values of cognitive scale were extracted from the included literatures. For the studies that did not directly report the change values, the change values were calculated by baseline, intervention endpoint, and follow-up endpoint. Stata 14 software was used for meta-analysis, and Q-test was used to measure heterogeneity. The GRADE quality of evidence system was used to evaluate the quality of evidence.

Seven studies involving 355 patients were included. Meta-analysis showed that AE could improve verbal learning (SMD=0.42, 95%CI 0.13-0.70, P<0.05), working memory (SMD=0.40, 95%CI 0.19-0.61, P<0.05), processing speed (SMD=0.45, 95%CI 0.10-0.80,P<0.05), attention/vigilance(SMD=0.40, 95%CI 0.04-0.76, P<0.05), reasoning and problem solving (SMD=0.43, 95%CI 0.06-0.80,P<0.05) of schizophrenia, but it may not improve visual learning (SMD=-0.18, 95%CI -0.70-0.33, P>0.05). Besides, At 2-3 months after cessation of aerobic exercise intervention, compared with the baseline, the scores of verbal learning (SMD=0.52,P<0.05), working memory (SMD=0.39,P<0.05), and processing speed (SMD=0.44,P<0.05) in the experimental group were higher than those in the control group at the endpoint of follow-up. Simultaneously, there was no significant difference in the scores of attention/vigilance and reasoning and problem solving between the two groups. Also, there was no significant difference in the cognitive function scores between the experimental and control groups at the endpoint of follow-up. The GRADE results showed that the evidence level of working memory was high, the level of verbal learning and attention/vigilance was moderate, and the level of processing speed, reasoning and problem-solving, visual learning were low.

Aerobic exercise help to improve the cognitive function in patients with schizophrenia, however, the improvement of visual-spatial memory is not significant. After stopping aerobic exercise, cognitive function tended to decrease gradually.

Schizophrenia; Cognition; Meta-analysis; Aerobic exercise