Heart failure in people younger than 50 years is more common in black than white americans and is closely associated with poorly treated and controlled hypertension: the cardia study

Abstract

HEART FAILURE IN PEOPLE YOUNGER THAN 50 YEARS IS MORE COMMON IN BLACK THAN WHITE AMERICANS AND IS CLOSELY ASSOCIATED WITH POORLY TREATED AND CONTROLLED HYPERTENSION: THE CARDIA STUDY Heart failure (HF) is a major public health issue that leads to substantial morbidity and mortality in the United States. Age, hypertension, and coronary ischemia are all well-documented risk factors for HF in older adults, but less is known about the incidence, risk factors, and demographics associated with HF in younger people. The Coronary Artery Risk Development in Young Adults (CARDIA) study, a 20-year multicenter longitudinal study of black and white men and women designed to investigate the development of coronary artery disease in young adults, offered an opportunity to explore these relationships. Beginning in 1985–1986, persons 18 to 30 years of age were enrolled from 4 American cities: Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; and Oakland, California. The cohort was well balanced with respect to self-reported race (52% black) and sex (55% women). Multiple clinical measurements, including blood pressure (BP), were obtained at baseline and after 2, 5, 7, 10, 15, and 20 years. BP was measured in standardized fashion, with hypertension defined as a BP of at least 140 ⁄90 mm Hg or use of antihypertensive medications. During both their study examinations and in yearly telephone follow-up, participants were asked about overnight hospitalizations. For each hospitalization, records were obtained and adjudicated for the presence of incident HF, defined as a hospitalization where the final diagnosis of HF was made by a treating physician and HF was treated with at least a diuretic and either digitalis or an afterload-reducing agent. Death was also reported to the study centers every 6 months, and each death was adjudicated to determine whether it was due to HF. In year 5, as part of the examination, participants underwent echocardiography. Systolic function was considered abnormal if the ejection fraction (EF) was either <40% or qualitatively described as abnormal; systolic function was considered borderline if the EF was 40% to 60%. Left ventricular hypertrophy (LVH) was defined as a left ventricular mass index at least 51 g ⁄m. Using multiple statistical tools, the CARDIA investigators compared baseline and subsequent development of risk factors in participants in whom HF did and did not develop. The CARDIA study enrolled 5115 individuals with a mean age of 25 years and a mean baseline BP around 110 ⁄70 mm Hg. The retention rate in the study was exceptionally high, with 87.5% of the original cohort completing the yearly telephone interview at year 20 and 71.8% completing the year 20 in-person examination. During the 20 years of follow-up, incident HF occurred in 27 patients (0.5%), which was more common than the incidence of myocardial infarction. Twenty-six of the 27 patients who developed incident HF were black. The cumulative incidence of HF was 1.1% in black women and 0.9% in black men, compared with 0.08% in white women and 0% in white men. From the Division of General Internal Medicine ⁄ Division of Cardiology, University of Nevada School of Medicine; Risk Reduction Center, Saint Mary’s Regional Medical Center, Reno, NV; Primary Care Service Line, Ralph H. Johnson VA Medical Center; and Division of General Internal Medicine ⁄Geriatrics, Medical University of South Carolina, Charleston, SC Address for correspondence: Michael J. Bloch, MD, Risk Reduction Center, Saint Mary’s Regional Medical Center, 645 North Arlington Street, Suite 460, Reno, NV 89503 E-mail: mbloch@aol.com