A Critical Evaluation of the Representation of Black Patients With Heart Failure and Preserved Ejection Fraction in Clinical Trials

BACKGROUND: In the United States, heart failure costs $34.4 billion annually and is associated with a mortality rate of 20% within 5 years of diagnosis. Heart failure preserved ejection fraction (HFpEF) accounts for 50% of all hospital admissions for heart failure. Black patients develop HFpEF at a significantly earlier age than do white patients, and the 5-year mortality rate for blacks with HFpEF is 30% to 44% higher compared with white patients. Current trials may not represent black patients proportionately to the general population. OBJECTIVE: The primary aim of this literature review was to critically evaluate the representation of black patients in HFpEF trials and propose solutions for future research. METHODS: PubMed and CINAHL were queried for peer-reviewed journal articles from 1997 to 2014 using 2 sets of search terms that included HFpEF or preserved left ventricular function and all relevant search terms for black patients. Initially, 182 articles were identified; however, after exclusionary criteria were applied, 22 articles remained. After critical review of each article for relevance, a total of 9 articles remained for the review. RESULTS: For the 9 trials reviewed including a total of 63,065 patients with HFpEF, 10,436 (17%) of the patients were black. Three of the 9 trials included less than 10% black patients, 4 trials included 10% to 20% black patients, and 2 trials included greater than 20% black patients. In 2 studies, the percentage of black patients in the HFpEF trial (13% and 17%) was significantly less than the percentage of black patients in the general regional population (53% and 39%), respectively. DISCUSSION: Although the mortality rate for black patients with HFpEF is 30% to 45% higher than the rate for white patients, 2 of the 9 studies did not have a representative sample of the general HFpEF population and none of the studies reported the objective of establishing a representative study population.