CONTEXT: Previous studies have documented an association of depression and phobic anxiety with cardiovascular morbidity and mortality, but little is known about the cardiovascular sequelae of panic anxiety. OBJECTIVE: To determine whether panic attacks are associated with risk of cardiovascular morbidity and mortality in postmenopausal women. DESIGN: Prospective cohort survey. SETTING: Ten clinical centers of the 40-center Women's Health Initiative. PARTICIPANTS: A total of 3369 community-dwelling, generally healthy postmenopausal women (aged 51-83 years) enrolled between 1997 and 2000 in the Myocardial Ischemia and Migraine Study who completed a questionnaire about occurrence of panic attacks in the previous 6 months. MAIN OUTCOME MEASURES: Cardiovascular/cerebrovascular outcomes (fatal and nonfatal myocardial infarction and stroke) and all-cause mortality were ascertained after a mean of 5.3 years of follow-up. RESULTS: A 6-month history of full-blown panic attacks, endorsed by 10% of postmenopausal women in this cohort, was associated with both coronary heart disease (hazard ratio, 4.20; 95% confidence interval, 1.76-9.99) and the combined end point of coronary heart disease or stroke (hazard ratio, 3.08; 95% confidence interval, 1.60-5.94) after controlling for multiple potential confounders. The hazard ratio for all-cause mortality, excluding those with a history of cardiovascular/cerebrovascular events, was 1.75 (95% confidence interval, 1.04-2.94). CONCLUSION: Panic attacks are relatively common among postmenopausal women and appear to be an independent risk factor for cardiovascular morbidity and mortality in older women.