Background: Because depression has been consistently demonstrated to be a risk factor for cardiac events, it is reasonable that anxiety might play a similar role. Higher rates of coronary heart disease have been reported in patients with phobia-related anxiety, including a six-fold increase in sudden death among male health professionals. The Myocardial Ischemia and Migraine Study (MIMS) previously reported that recent panic attacks in postmenopausal women were associated with a higher incidence of ischemic and nonischemic chest pain. Smoller and colleagues examined whether this trend could also be associated with increased cardiovascular morbidity and mortality.

The Study: The authors reviewed data from MIMS, a prospective auxiliary study performed in conjunction with the Women's Health Initiative (WHI) Observational Study. MIMS participants completed annual questionnaires about their health status, including whether they had experienced panic attacks in the previous six months. The presence of depression, other health conditions, and a history of coronary heart disease, stroke, or hypertension was also recorded at baseline. The health status of each patient was monitored annually by questionnaire, clinical data, and, when necessary, death certificates and autopsy reports. Participants who were enrolled in the WHI clinical trials of hormone therapy were excluded from MIMS.

Results: The analysis included 3,369 post-menopausal women, 51 to 83 years of age, who were followed for a mean duration of 5.3 years after enrollment; there were 41 coronary heart disease events (fatal and non-fatal myocardial infarction) and 40 strokes reported during this period.

Women who had reported at least one panic attack in the six months before study initiation were more likely to have had a history of cardiovascular disease and associated risk factors (e.g., smoking, higher body mass index, diabetes, hypertension) at baseline. After adjusting for these conditions, full-blown panic attacks remained independently associated with a greater likelihood of having coronary heart disease, the combined end point of coronary heart disease or stroke, and overall mortality (hazard ratios of 4.20, 3.08, and 1.75, respectively), an association that remained after adjusting for depression. Patients who exhibited some symptoms of panic attacks but not enough to meet the strict clinical definition showed similar, although less marked, associations with these outcomes.

Conclusion: Postmenopausal women who had experienced panic attacks in the preceding six months had a fourfold greater risk of coronary heart disease and a nearly twofold increase in overall mortality during a five-year follow-up period. After controlling for cardiac risk factors and depression, panic attacks appear to be an independent marker for cardiovascular illness among postmenopausal women.