Causal Association Between Obstructive Sleep Apnea and Migraine: A Bidirectional Mendelian Randomization Study.

Objective: Patients with obstructive sleep apnea (OSA) frequently suffer from migraine, however the causal relationship between OSA and migraine is unknown. Investigating the causation will assist in understanding the etiology of OSA and migraine.

Methods: Bidirectional two-sample Mendelian randomization (MR) and multivariable MR (MVMR) approaches were carried out to investigate the causal link between OSA and migraine. The public genome-wide association study (GWAS) data for OSA, migraine, and subtypes were obtained from the IUE open GWAS project and the FinnGen consortium. To investigate the causal links between OSA and migraine, inverse variance weighted (IVW) analysis was used in conjunction with four additional statistical approaches. Furthermore, sensitivity studies were performed using heterogeneity and pleiotropy tests to assess the estimation's robustness.

Results: In general, our findings suggested that the OSA is causally associated with migraine with aura (MA, IVW: OR = 1.147; 95% CI = 1.016-1.295; P = 0.026), which was confirmed with the MVMR analysis further (OR = 1.184, 95% CI = 1.028-1.364, P = 0.020). In addition, increased risk of migraine and migraine without aura on OSA occurrence were identified in the reverse analysis, but these results were subsequently negated with MVMR analysis.

Conclusion: According to the current findings, there was a preliminary causal effect of OSA on MA among European descendants.

Clinical relevance: These findings suggest a potential causal effect of OSA on migraine and provide new insights to prevent and manage the two disorders.