Habitual sleep disturbances and migraine: a Mendelian randomization study.
Daghlas I., Vgontzas A., Guo Y., Chasman DI., International Headache Genetics Consortium None., Saxena R.
OBJECTIVE: Sleep disturbances are associated with increased risk of migraine, however the extent of shared underlying biology and the direction of causal relationships between these traits is unclear. Delineating causality between sleep patterns and migraine may offer new pathophysiologic insights and inform subsequent intervention studies. Here, we used genetic approaches to test for shared genetic influences between sleep patterns and migraine, and to test whether habitual sleep patterns may be causal risk factors for migraine and vice versa. METHODS: To quantify genetic overlap, we performed genome-wide genetic correlation analyses using genome-wide association studies of nine sleep traits in the UK Biobank (n ≥ 237,627), and migraine from the International Headache Genetics Consortium (59,674 cases and 316,078 controls). We then tested for potential causal effects between sleep traits and migraine using bidirectional, two-sample Mendelian randomization. RESULTS: Seven sleep traits demonstrated genetic overlap with migraine, including insomnia symptoms (rg = 0.29, P