Racial disparity in the control of hypertension contributes to the deaths of almost 8,000 black men and women in the United States annually, according to a first-of-its-kind study published today in the Annals of Family Medicine by University of Rochester Medical Center researchers.

The researchers concluded that the deaths could be avoided or postponed if blacks had their hypertension, or high blood pressure, controlled to the same level as whites.

"Disparity in the control of blood pressure is one of the most important, if not the most important, contributor to racial disparity in cardiovascular mortality, and probably overall mortality," said Kevin Fiscella, M.D., M.P.H., lead author of the article and associate professor of family medicine and of community and preventive medicine at the Medical Center.

"If we as clinicians are going to reduce cardiovascular and stroke-related deaths, we need to pay attention to all the barriers to improving blood pressure control, particularly for minority patients" Fiscella said.

Although not clearly known, the likely causes of the racial disparity include differences in access to care, clinician management and communication, hypertension severity, and patient adherence.

"There is evidence from previous studies that access barriers and financial and interpersonal communication barriers affect the ability of black patients to get medical care or to take their medication as prescribed," Fiscella said.

Fiscella and Kathleen Holt, Ph.D., adjunct professor of community and preventive medicine at the Medical Center, are authors of the articles, which is the first effort to quantify the toll of racial disparity in blood pressure control. The article is part of a package of articles on racial disparity in the Annals of Family Medicine that is accompanied by editorials from former U.S. Surgeon General David Satcher, M.D., Ph.D., and Crystal Wile Cené, M.D., M.P.H., and Lisa A. Cooper, M.D., M.P.H. They call on clinicians, researchers, health care administrators, health care planners and policy makers to work together to gain a better understanding of the barriers faced by ethnic minorities.

Hypertension is a precursor to cardiovascular disease, which is the leading cause of death in the United States and which occurs at the highest rate among black Americans. The researchers analyzed data of 1,545 black adults and 1,335 white adults. The mean blood pressure among blacks with hypertension was approximately six mm/Hg (millimeters of mercury) higher than that for the total adult black population and seven mm/Hg higher than that for whites with hypertension.

A reduction in mean blood pressure among blacks to that of whites would reduce the annual number of deaths among blacks from heart disease by 5,480 and from stroke by 2,190, the researchers concluded.

"There is evidence for racial disparity in patient adherence to antihypertensive medication, including studies conducted within the Veterans Administration Health System, where fewer differences in access appear to exist," the researchers state in the article. "Differences in adherence by race may be due to affordability of medicines, personal beliefs, anticipated adverse effects, and health literacy that disproportionately affect blacks. Although multiple causes may contribute to racial disparity in blood pressure control, this disparity is not inevitable. Disparity in hypertension control is significantly smaller in the Veterans Administration Health System, where access barriers are fewer."

Elimination of racial disparity in blood pressure control is an attainable goal, provided sufficient resources are available to discover and address adherence barriers, the researchers conclude.

Funding for the research was provided by the Robert Wood Johnson Foundation and through a grant from the National Heart, Lung, and Blood Institute.

Michael Wentzel
University of Rochester Medical Center