Objectives: To evaluate whether phobic anxiety is associated with increased risk of cardiac mortality in individuals with established coronary heart disease (CHD) and to examine the role of reduced heart rate variability (HRV) in mediating this risk. Previous findings suggest that phobic anxiety may pose increased risk of cardiac mortality in medically healthy cohorts.
Methods: We performed a prospective cohort study in 947 CHD patients recruited during hospitalization for coronary angiography. At baseline, supine recordings of heart rate for HRV were collected, and participants completed the Crown-Crisp phobic anxiety scale. Fatal cardiac events were identified over an average period of 3 years.
Results: Female CHD patients reported significantly elevated levels of phobic anxiety when compared with male patients (p < .001), and survival analysis showed an interaction between gender and phobic anxiety in the prediction of cardiac mortality (p = .058) and sudden cardiac death (p = .03). In women, phobic anxiety was associated with a 1.6-fold increased risk of cardiac mortality (hazard ratio, 1.56; 95% confidence interval, 1.15-2.11; p = .004) and a 2.0-fold increased risk of sudden cardiac death (hazard ratio, 2.02; 95% confidence interval, 1.16-3.52; p = .01) and was unassociated with increased mortality risk in men (p = .56). Phobic anxiety was weakly associated with reduced high-frequency HRV in female patients (r = -.14, p = .02), but reduced HRV did not alter the association between phobic anxiety on mortality.
Conclusions: Phobic anxiety levels are high in women with CHD and may be a risk factor for cardiac-related mortality in women diagnosed with CHD. Reduced HRV measured during rest does not seem to mediate phobic anxiety-related risk.