Serum uric acid not causally linked to major depressive disorder

There appears to be no significant association between serum uric acid (SUA) and major depressive disorder (MDD), suggest the results of a meta-analysis and two-sample bidirectional Mendelian randomization (MR) study.

“Although previous epidemiological studies have demonstrated that SUA is associated with MDD, these analyses are prone to biases,” the authors said. “Here, we applied the MR approach to determine whether SUA is causally associated with MDD.”

The meta-analysis was carried out to assess the relationship between SUA and MDD. The authors applied summary data from the Global Urate Genetics Consortium and the Psychiatric Genomics Consortium to estimate their causal effect via MR analysis. Then, they further examined the causal effect using genetic risk scores (GRS) as instrumental variables.

Overall, 6,975 patients with MDD and 13,689 controls were included in the meta-analysis, which revealed that SUA was associated with MDD (standardized mean difference, ‒0.690, 95 percent confidence interval, ‒0.930 to ‒0.440; I², 97.4 percent; p<0.001).

On the other hand, the five MR methods showed no causal relationship between SUA and MDD. This finding verified the results obtained from the GRS approach.

“This paper found little evidence that this association between SUA and MDD is casual,” the authors said. “Genetically, there was no significant causal association between SUA and MDD.”