Abstract
BACKGROUND: The possible causative relationship between migraine and postpartum depression (PPD) is examined in this study. Prior research has shown a strong correlation between the two conditions, but the exact cause is unknown. METHODS: A bidirectional Mendelian randomization (MR) approach was employed to assess causality, utilizing discovery and replication samples from publicly available genome-wide association study (GWAS) datasets. Causal effects were estimated using the inverse-variance weighted (IVW) method, MR-Egger regression, and three additional MR approaches. Sensitivity analyses, including tests for heterogeneity, horizontal pleiotropy, and leave-one-out analysis, were conducted to evaluate the robustness of the findings. RESULTS: Overall, no significant causal effect of migraine on PPD risk was identified in either the discovery (IVW: OR=1.018; 95% CI=0.928-1.117; P=0.706) or replication analysis (IVW: OR=2.097; 95% CI=0.328-13.409; P=0.434) in forward MR analysis. Similarly, no causal effect of migraine on PPD was observed in female-only analyses. Moreover, reverse MR analysis found no significant causal effect of PPD on migraine risk in discovery (IVW: OR=1.036; 95% CI=0.999-1.075; P=0.057) or replication (IVW: OR=1.001; 95% CI=1.000-1.002; P=0.274) analysis, and no causal effect was observed in female-only analyses. No evidence of heterogeneity or horizontal pleiotropy was detected in sensitivity tests. CONCLUSION: The current MR study indicates no significant causal relationship between migraine and PPD.