Frequency of angina pectoris and secondary events in patients with stable coronary heart disease (from the Heart and Soul Study)

Abstract

The extent to which angina pectoris (AP) predicts secondary cardiovascular events beyond independent of measures of disease severity is unknown. We evaluated the association between AP frequency and secondary events in patients with stable coronary heart disease (CHD). We administered the Seattle Angina Questionnaire to 1,023 participants with stable CHD enrolled from September 2000 to December 2002 and followed for a median of 8.9 years. We used Cox proportional hazards to evaluate the association of AP frequency with death and subsequent hospitalization for AP, revascularization, myocardial infarction (MI), or heart failure. At enrollment, 633 (62%) participants reported no AP, 279 (27%) reported monthly AP, and 111 (11%) reported daily or weekly AP. During follow-up, 396 participants died, 204 were hospitalized for AP, 194 for revascularization, 140 for MI, and 188 for heart failure. Compared with participants without AP, participants with daily or weekly AP were more likely to be hospitalized for AP (hazard ratio [HR] 3.3; 95% confidence interval [CI] 2.3 to 4.7; p<0.001), revascularization (HR 2.0; 95% CI 1.3 to 2.9; p=0.001), or heart failure (HR 1.6; 95% CI 1.0 to 2.5; p=0.03) and more likely to die (HR 1.5; 95% CI 1.1 to 2.0; p=0.01). AP was not independently associated with MI (HR 1.3; 95% CI 0.8 to 2.3; p=0.29). After adjusting for demographics, co-morbidities, treadmill exercise capacity, ejection fraction, and inducible ischemia, frequency of AP remained independently associated with hospitalization for AP (HR 2.4; 95% CI 1.6 to 3.6; p<0.001), revascularization (HR 1.7; 95% CI 1.1 to 2.7; p=0.02), and death (HR 1.4; 95% CI 1.0 to 2.0; p=0.045). In conclusion, in outpatients with stable CHD, AP frequency predicts higher rates of secondary cardiovascular events and death, independent of objective measures of disease severity.