A unique cardiovascular disease (CVD) risk calculator for black adults may not be necessary, a study found, despite that fact that current prediction models were developed with predominantly white populations.
Using data from the Jackson Heart Study (JHS), a community-based study of 5,301 black adults in Jackson, Miss., researchers developed and validated risk prediction models for CVD incidence in black adults, incorporating standard risk factors, biomarkers, and subclinical disease. The studied outcome was the first occurrence of myocardial infarction, coronary heart disease death, congestive heart failure, stroke, incident angina, or intermittent claudication.
Model performance was compared with the American College of Cardiology/American Heart Association (ACC/AHA) CVD risk algorithm (Pooled Cohort Equations) and the Framingham Risk Score (FHS) refitted to the JHS data. The study appeared Feb. 24 in JAMA Cardiology.
The study cohort included 3,689 participants. Over a median of 9.1 years, 270 participants (166 women) experienced a first CVD event. Six models composed of different risk variables were constructed and externally validated using 2 independent black adult data sets from the Atherosclerosis Risk in Communities (ARIC) study and the Multi-Ethnic Study of Atherosclerosis (MESA). Statistical analysis included the C statistic, a measure used to estimate the probability that a model is able to predict an outcome, with values ranging from 0.5, indicating that the outcome is no different than chance, to 1.0, in which the model predicts the outcome perfectly.
A simple combination of standard CVD risk factors, B-type natriuretic peptide, and ankle-brachial index (model 6) yielded modest improvement over a model without B-type natriuretic peptide and ankle-brachial index (C statistic, 0.79; 95% CI, 0.75 to 0.83 [relative integrated discrimination improvement, 0.22; 95% CI, 0.15 to 0.30]). However, the reclassification improvement was not substantially different between model 6 and the ACC/AHA CVD Pooled Cohort risk equations or between model 6 and the FHS. The models discriminated reasonably well in the ARIC and Multi-Ethnic Study of Atherosclerosis data (C statistic range, 0.70 to 0.77).
“Previous risk algorithms were developed in predominantly white populations, and validation in black populations has been limited,” the authors wrote. “Based on our results, these selected models that are readily available in the primary care setting are likely generalizable to other black populations originating from different geographical regions within the United States.”
An editorial stated that the study reinforces the usefulness of ACC/AHA CVD Pooled Cohort risk equations and the importance of efforts to implement the current guidelines to prevent atherosclerotic cardiovascular disease in African Americans.
“Because African Americans are a high-risk population, the ability to estimate that risk is an important step forward in efforts to prevent ASCVD and eliminate health disparities,” the editorial stated. “We believe that future research on risk estimation could usefully focus on several issues, including risk estimation in other racial/ethnic groups, prediction of an expanded outcome to include HF [heart failure], and the role of easily attainable measures of subclinical disease in risk prediction.”