Increased risk of essential tremor in migraine: A population-based retrospective cohort study

Purpose To examine the long-term risk of essential tremor (ET) in migraine. Methods Using population-based administrative data from a subset of the National Health Insurance Research Database (NHIRD) of Taiwan, we identified 22,696 newly diagnosed migraineurs (mean age 44.5 years) and a matched migraine-free cohort of 90,784 individuals in the period 2000-2008. Multivariable Cox proportional hazards regression analysis was conducted for assessing the ET risk for the migraine cohort compared to the migraine-free cohort. Results After adjusting for covariates, the migraine cohort had a 1.83-fold increased risk (95% CI 1.50-2.23) of subsequent ET in comparison to the migraine-free cohort (8.97 vs. 4.81 per 10,000 person-years). In the subgroup analysis, patients with migraine were associated with higher risks of ET, regardless of gender, age or the existence of comorbidities. Conclusion Our findings demonstrated an association between migraine and ET, suggesting a possible shared pathophysiology underpinning both disorders.