Abstract 2095: Racial Patterns in the Evaluation of Coronary Artery Disease in Asymptomatic Patients with Type 2 Diabetes
Prior research suggests that African-Americans (AAs) are less likely to be referred for invasive coronary evaluation. There are limited data, however, on referral patterns in AAs with diabetes (DM), despite their higher risk of cardiovascular (CV) complications. Performance of coronary angiography (CA), along with extent and treatment of coronary artery disease (CAD) risk factors were assessed in 1123 subjects enrolled in the Detection of Ischemia in Asymptomatic Diabetics (DIAD) Study; 522 were randomized to CAD screening with pharmacological stress myocardial perfusion imaging. Subjects’ physicians were informed of results and further evaluation was left to their discretion. Over the next 3–5 years, cardiac stress testing (CST) was also performed in 139 subjects outside of the study protocol. Baseline demographic characteristics: 54% male; 22% ethnic minority (17% AA); mean age 61±6 years; and mean duration of type 2 DM of 8±7 years. AAs were more likely to smoke (16%) vs Whites (8%; p = .003), have hypertension or be on an anti-hypertensive (66% vs 55%; p = .003), have elevated body mass index (p < .0001), HbA1c (p < .0001), systolic (p = .004) and diastolic blood pressure (p = .0001) levels, and were less likely to be prescribed a lipid-lowering drug (41% vs 49%; p = .02). A total of 661 (59%) subjects had CST, and of these 175 (27%) had an abnormality (AAs 22%, Whites 28%; p = .42). Of subjects with an abnormal CST, 60 (34%) underwent CA (AAs 24%, Whites 37%; p = .26). In multivariate logistic regression analyses, adjusting for age (OR = 0.96 per year; 95% CI 0.92,0.99), DM duration (OR = 1.06 per year; 95% CI 1.03,1.09), income (OR = 0.47 for > $50K; 95% CI 0.24,0.92), and presence of an abnormal CST (OR = 7.9; 95% CI 4.8,12.9), AAs were less likely to undergo CA (OR = 0.38; 95% CI 0.16,0.91). The presence of moderate or severe CAD on CA was similar: 52% of Whites and 40% of AAs (p = .55). Thus, invasive evaluation following abnormal CST is less common in AAs with type 2 DM than in Whites, despite more adverse CV risk profiles. Further investigation into the disproportionate follow-up of silent CAD requires further investigation.