Increased risk of trigeminal neuralgia in patients with migraine: A nationwide population-based study.

Objectives The objectives of this article are to evaluate the association between migraine and trigeminal neuralgia and to investigate the effects of age, sex, migraine subtype, and comorbid risk factors on trigeminal neuralgia development. Methods This population-based cohort study was conducted using data from Taiwan's National Health Insurance Research Database. Individuals aged ≥ 20 years with neurologist-diagnosed migraine between 2005 and 2009 were included. A non-headache age-, sex-, and propensity score-matched control cohort was selected for comparison. All participants were followed until the end of 2010, death, or the occurrence of trigeminal neuralgia. Cox proportional hazards regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for comparison of the risk of trigeminal neuralgia between groups. Results Both cohorts ( n = 137,529 each) were followed for a mean of 3.1 years. During the follow-up period, 575 patients (421,581 person-years) in the migraine cohort and 88 matched controls (438,712 person-years) were newly diagnosed with trigeminal neuralgia (incidence rates, 136.39 and 20.06/100,000 person-years, respectively). The HR for trigeminal neuralgia was 6.72 (95% CI, 5.37-8.41; p < 0.001). The association between migraine and trigeminal neuralgia remained significant in sensitivity analyses. Among migraine subtypes, patients with migraine with aura were at greater risk of trigeminal neuralgia development. No other significant interaction was identified in subgroup analyses. Conclusions Migraine is a previously unidentified risk factor for trigeminal neuralgia. The association between these conditions suggests a linked underlying mechanism, which is worthy of further exploration.