Abstract
Data on the association of the MTHFR 677C→T and ACE D/I polymorphisms with migraine severity, measured by attack frequency, are scarce. We performed an association study among 24 961 women participating in the Women's Health Study. Migraine, aura status and attack frequency were self-reported. Multinomial logistic regression was used to investigate the genotype-migraine association. Among the 3186 migraineurs with complete genotype and attack frequency data, 1270 reported migraine with aura (MA) (attack frequency 76 ≥ weekly; 219 monthly; 123 every other month; 852 fewer than six times/year) and 1916 migraine without aura (MoA) (attack frequency: 85 ≥ weekly; 414 monthly; 208 every other month; 1209 fewer than six times/year). The MTHFR 677TT genotype was associated with a reduced risk for MA, which only appeared for attacks fewer than six times/year (age-adjusted odds ratio 0.78; 95% confidence interval 0.61, 0.99). We did not find a specific pattern of association of the ACE D/I polymorphism with attack frequency for MA or MoA.