Prevalence and impact of migraine.

Knowledge of the epidemiology of migraine has expanded because of the recent proliferation of large scale population-based studies using standardized case definitions. Migraine is a highly prevalent disorder, affecting about 6% of men and 15% to 18% of women. Migraine prevalence is highest between the ages of 25 and 55 years, accounting for its enormous impact in the workplace. Migraine imposes a substantial burden on society as measured by direct and indirect costs. Because the indirect costs greatly exceed the direct costs and because migraine is underdiagnosed and undertreated, improvements in treatments in treatment should reduce individual suffering and reduce work loss in a cost-effective manner.