Syncope in migraine - The population-based CAMERA study

Objective: To examine the association between migraine and syncope-related autonomic nervous system (ANS) symptoms. Methods: A population-based study among migraineurs with and without aura (n = 323) and control subjects (n = 153) was conducted. A systematic questionnaire and cardiovascular measurements during rest, while standing, and after venipuncture addressed the prevalence of syncope, orthostatic intolerance, orthostatic hypotension (OH), and the postural tachycardia syndrome (POTS) in migraineurs and control subjects. Results: The lifetime prevalence of syncope in all participants was 41%, more often in women (45 vs 32%; p = 0.02). Compared with control subjects, migraineurs had a higher lifetime prevalence of syncope (46 vs 31%; p = 0.001), frequent syncope (five or more attacks) (13 vs 5%; p = 0.02), and orthostatic intolerance (32 vs 12%; p = 0.001). There was no association between ANS symptoms and the severity of migraine or migraine subtype. Cardiovascular measurements and the prevalence of POTS and OH did not differ significantly between migraineurs and control subjects. Conclusion: This population-based study demonstrated an elevated prevalence of syncope and orthostatic intolerance in migraineurs without clear interictal signs of autonomic nervous system dysfunction.