Migraine headache in a prepaid health plan: ascertainment, demographics, physiological, and behavioral factors.

BACKGROUND

Migraine is a prevalent disorder whose relationship to other conditions remains poorly understood.

METHODS

Associations between migraine and physiological, behavioral, and demographic characteristics were assessed in a retrospective cohort study of 79,588 enrollees in a large prepaid health maintenance organization who underwent a multiphasic preventive health checkup in 1971-1973.

RESULTS

Migraine was found to be inversely associated with age and education and strongly associated with the female sex. The likelihood of migraine was significantly higher among blacks, smokers, those who drink more than six cups of coffee per day, those with Raynaud's syndrome, and those with a family history of migraine. The magnitude of associations between migraine and other factors was, in general, reduced among those with a self-reported physician diagnosis of migraine compared to those whose migraine status was defined on the basis of reported symptoms.

CONCLUSIONS

Migraine prevalence was found to be higher in blacks and other unspecified minorities than in the white population. The magnitude of the associations between migraine and behavioral risk factors was strongly influenced by the method of migraine ascertainment. The inverse association with level of education suggests that social causation or drift may have been operating in this disease in the early 1970s, 15 to 20 years earlier than recent population-based studies would suggest. Further research is needed to fully appreciate the spectrum of disease and behaviors associated with migraine.