One-Fifth of Patients with Stable CAD Experience Monthly Angina

More than 20% of stable outpatients with coronary artery disease (CAD) reported experiencing angina at least once per month, according to a study published in JAMA Network Open.

“Angina pectoris (angina) is a common symptom of obstructive CAD and is associated with major adverse cardiovascular events, reduced quality of life, and higher costs of care,” wrote the authors.

What Is the Prevalence of Angina in Patients with CAD?

This study involved telephone-based administration of the Seattle Angina Questionnaire–7 (SAQ-7) between February and July 2017. The investigators identified and contacted 4,139 patients aged ≥30 years with established CAD receiving primary care through an integrated primary care network. In total, 1,612 patients (38.9%) responded to the survey. Average age of respondents was 71.8 years, and 577 (35.8%) were women. The majority of patients were white (82.8%), 4.7% were Black, and 5.7% were Hispanic. More than half of patients (60.4%) were insured by Medicare. One-third were insured by commercial insurance and 5.2% were insured by Medicaid.

Compared to non-respondents, patients who responded to the survey tended to be younger (mean age, 73.2 vs. 71.8 years), were more likely to speak Spanish (5.3% vs. 9.1%), and were more likely to have Medicaid insurance (4.2% vs. 5.2%).

Incidence of angina at least monthly was 21.2%. Among these patients, 12.5% reported experiencing daily or weekly angina, compared with 8.7% who reported angina occurring once monthly. More than three-quarters of patients (78.8%) reported no incidence of angina. The mean SAQ-7 score was 93.7 (standard deviation [SD], 13.7).

“Understanding this baseline prevalence and covariates associated with having angina among primary care patients is important for several reasons,” wrote the authors. “Primary care physicians (PCPs) are the primary source of care continuity for most patients with known and unknown CAD and are, therefore, ideally positioned to screen for and identify underrecognized and undertreated angina.”

What Factors Are Associated with Angina?

After multivariate analysis, factors associated with more frequent angina included speaking a language other than Spanish or English (odds ratio [OR], 5.07; 95% confidence interval [CI], 1.39-18.50), Black race (OR, 2.01; 95% CI, 1.08-3.75), current smoking (OR, 1.88; 95% CI, 1.27-2.78), former smoking (OR, 1.69; 95% CI, 1.13-2.51), atrial fibrillation (OR, 1.52; 95% CI, 1.02-2.26), and chronic obstructive pulmonary disease (OR, 1.61; 95% CI, 1.18-2.18). Male sex (OR, 0.63; 95% CI, 0.47-0.86), peripheral artery disease (OR, 0.63; 95% CI, 0.44-0.90), and novel oral anticoagulant use (OR, 0.19; 95% CI, 0.08-0.48) were associated with less frequent angina incidence.

According to the authors, limitations of the study include the survey response rate, which “may limit the generalizability” of the findings. In addition, the study only assessed angina incidence at a single point in time and cannot draw conclusions about patterns in incidence.

In conclusion, the authors wrote, “Among stable outpatients with CAD receiving primary care through an integrated primary care network, 21.2% of surveyed patients reported experiencing angina at least once monthly. Several objective demographic and clinical characteristics were associated with angina frequency. Proactive assessment of angina symptoms using validated assessment tools and estimation of patients at higher risk of suboptimally controlled angina may be associated with reduced morbidity.”