Seasonal Variation and Diurnal Rhythmicity of Migraine Attacks in Patients from a North Indian Tertiary Care Center.

Migraine is a widespread and debilitating disorder. Recent evidence suggests a role of seasonal and circadian rhythmicity in migraine episodes. We investigated the pattern of migraine attacks over 1 year in the North Indian population. A questionnaire was provided to 120 migraine patients at the end of each of the six seasons according to the Indian calendar. The frequency, pain intensity, and duration of migraine episodes were significantly higher during the hot summer (7.92 ± 0.70, 6.63 ± 0.17, and 8.73 ± 0.99, respectively) and monsoon (8.11 ± 0.72, 6.64 ± 0.17, and 8.00 ± 0.94, respectively) compared to the cold winter months. There was a gradual decrease from summer to winter, with 77.2% of patients reporting diurnal rhythmicity to their attacks, and 34.5% of patients reporting occurrences in the afternoons, increasing from colder to hotter months. Increased incidence during summer, monsoon, and afternoons should be considered in planning prophylactic and therapeutic interventions.