Background: Age, race, education, and diabetes have been associated with differences in anginal symptoms, treatments, and outcomes among outpatients with coronary artery disease (CAD), but there is little data on whether such characteristics affect relationships between anginal symptoms and mortality.
Methods: Using a prospective cohort design, we examined associations of anginal symptoms, as assessed by the Seattle Angina Questionnaire, with total mortality among 8908 outpatients with CAD to investigate whether this relationship is influenced by patient demographic or clinical characteristics. Potential effect modification was primarily assessed for age, race, education, and diabetes, and secondarily assessed for smoking, prevalent congestive heart failure (CHF), myocardial infarction, and coronary revascularization.
Results: Over 2 years mean follow-up, there were 896 deaths. After adjustment for potential confounders, persons reporting greater physical limitation due to angina had higher mortality: 27% higher with mild limitation (hazard ratio [HR] 1.27, 95% CI 0.98-1.64), 61% higher with moderate limitation (HR 1.61, 95% CI 1.27-2.05), and 2.5-fold higher with the greatest limitation (HR 2.55, 95% CI 1.97-3.30), compared with little or no limitation (P for trend <.001). Anginal instability was also independently predictive of mortality. There was little evidence that these relationships varied by age, race, education, diabetes, smoking, or presence of CHF, prior myocardial infarction, or prior coronary revascularization (P for each interaction >.28). Anginal symptoms predicted higher mortality risk comparable to a decade of age difference, presence of diabetes, or presence of CHF.
Conclusions: Among outpatients with CAD, self-reported anginal symptoms consistently predict mortality irrespective of differences in age, race, education, or clinical comorbidities.