BACKGROUND

Previous observational studies have discovered a connection between depression and mineral status. Confirming this potential connection is challenging due to confounding factors and potential reverse causality which is inherent in observational studies.

MATERIALS AND METHODS

We performed a Mendelian randomization (MR) analysis to estimate the causal association of serum minerals with depression. Leveraging summary-level data on depression, a genome-wide association study (GWAS) was applied. The data on serum minerals were collected from the FinnGen Biobank database. MR assessments representing causality were produced by inverse-variance weighted approaches with multiplicative random and fixed effects.

RESULT

Sensitivity analyses were performed to validate the reliability of the results. A noteworthy correlation emerged between serum zinc levels and reduced risk of depression. An odds ratio (OR) of 0.917 for depression associated with a one standard deviation increase in serum zinc levels (OR = 0.968; 95% CI = 0.953-0.984, p = 1.19 × 10-4, random effects model inverse variance weighted (IVW)); (OR = 0.928; 95% CI = 0.634-1.358, p = 0.766, MR Egger). Sensitivity assessments supported this causation. However, the risk of depression did not exhibit an association with other minerals.

CONCLUSIONS

In summary, a higher zinc concentration is causally associated with a reduced depression risk. This MR outcome may assist clinicians in the regulation of specific mineral intake, particularly for high-risk patients with serum zinc deficiencies.