Study on association of serum uric acid levels with bipolar disorder: systematic review and meta-analysis in Chinese patients

BACKGROUND: The purine system represented by uric acid may be involved in the pathogenesis of bipolar disorder, This study intends to explore the association of serum uric acid levels with bipolar disorder in Chinese patients through meta-analysis. METHODS: Electronic databases, including PubMed, Embase, Web of Science, and China National Knowledge Infrastructure (CNKI), searching from inception to December 2022. Randomized Controlled Trials that reported serum uric acid levels and bipolar disorder were included. Two investigators independently extracted data and RevMan5.4 and Stata14.2 were used for statistical analyses. RESULTS: Twenty-eight studies with 4482 bipolar disorder, 1568 depression, 785 schizophrenia, and 2876 healthy control subjects were included in this meta-analysis. The results of the meta-analysis showed that serum uric acid levels in the bipolar disorder group were significantly higher than those in depression [SMD 0.53 (0.37, 0.70), p < 0.00001], schizophrenia [SMD 0.27 (0.05, 0.49), p = 0.02] and healthy control group [SMD 0.87 (0.67, 1.06), p < 0.00001]. Subgroup-analysis showed that in Chinese people with bipolar disorder, uric acid levels of the manic episode were higher than the depressed episode [SMD 0.31 (0.22, 0.41), p < 0.00001]. CONCLUSION: Our results indicated a strong association between serum uric acid levels and bipolar disorder in Chinese patients, but further studies about whether uric acid levels can be a biomarker for bipolar disorder still need to investigate.