Background: Blood–oxygen-level dependent functional magnetic resonance imaging (BOLD-fMRI) maps cerebral activity by the hemodynamic response. Catechol-O -methyltransferase (COMT ) gene is involved in the metabolism of dopamine. It is reported that both of these can be used to assess the aggression risk in patients with schizophrenia. However, these methods to assess the aggression risk patients with schizophrenia have not been established in China. Therefore, we deliver here a systematic review and meta-analysis based on the studies dealing with Chinese patients.
Method: Nine fMRI studies and 12 gene studies were included. The data of each study were extracted and summarized. Odds ratios with 95% confidence intervals were estimated on allele, dominant, and recessive models. Publication bias was evaluated by Begg’s funnel plot.
Results: Positive BOLD-fMRI values in the lower central neural system (CNS) and negative values in the high-level CNS were observed in the patients with aggression risk. A strong association was derived from the recessive gene model of COMT  polymorphism rs4680 and risk in aggression behavior (odds ratio =2.10). No significant publication bias was identified.
Conclusion: Aggression behavior in patients with schizophrenia can be indicated by positive BOLD-fMRI values in the lower CNS and negative values in the high-level CNS and by a recessive gene model in COMT  polymorphism rs4680. A combined test of fMRI and COMT  gene could increase the predictive value.
Keywords: aggression, schizophrenia, Chinese, fMRI, COMT, meta-analysis