Lightning and its association with the frequency of headache in migraineurs: an observational cohort study.

AimThe aim of this article is to determine if lightning is associated with the frequency of headache in migraineurs.MethodsParticipants fulfilling diagnostic criteria for International Headache Society-defined migraine were recruited from sites located in Ohio (n = 23) and Missouri (n = 67). They recorded headache activity in a daily diary for three to six months. A generalized estimating equations (GEE) logistic regression determined the odds ratio (OR) of headache on lightning days compared to non-lightning days. Other weather factors associated with thunderstorms were also added as covariates to the GEE model to see how they would attenuate the effect of lightning on headache.ResultsThe mean age of the study population was 44 and 91% were female. The OR for headache was 1.31 (95% confidence limits (CL); 1.07, 1.66) during lighting days as compared to non-lightning days. The addition of thunderstorm-associated weather variables as covariates were only able to reduce the OR for headache on lightning days...