Where You Live Is a Factor in Hypertension

Dec. 6, 2010 -- Race, place, and gender appear to be strongly associated with high blood pressure, a major risk for heart disease and stroke, according to new data.

A 20-year study involving more than 3,400 young, initially healthy adults in four urban areas found that the risk of developing high blood pressure was higher in the South compared to the North; hypertension rates were highest in African-American women and lowest in white women.

Understanding which regions and populations are at greatest risk could help experts target better interventions for these groups.

Researchers led by Deborah A. Levine, MD, MPH, assistant professor of internal medicine at the University of Michigan Medical School in Ann Arbor, analyzed data from the Coronary Artery Risk Development in Young Adults (CARDIA) study. This study included information on black and white men and women who were between the ages of 18 and 30 during 1985 and 1986, when the study began, and who lived in Birmingham, Ala.; Chicago; Minneapolis, Minn.; or Oakland, Calif.

The participants were followed for the next 20 years to see who developed high blood pressure. The groups were matched for race, gender, and initial health status.

Even after taking account many of the lifestyle factors that are known to contribute to high blood pressure -- such as obesity, smoking, family history, and physical activity -- geography, race, and gender were still independently associated with a higher incidence of high blood pressure.

Tracking Blood Pressure by Geography, Race, and Gender

Among the researchers’ findings:

• High blood pressure was more likely to affect African-Americans compared with whites, and the highest rates were seen in African-American women. By the end of the study, 37.6% of African-American women and 34.5% of African-American men had developed hypertension, whereas the rates were lower in white men at 21.4% and lowest among white women at 12.3%.
• Birmingham, Ala., had the highest incidence of hypertension at 33.6% and Minneapolis, Minn., had the lowest at 19%. High blood pressure incidence was 27.4% in Oakland, Calif., and 23.4% in Chicago.

The results are published in the January 2011 issue of Hypertension: Journal of the American Heart Association.

Cardiovascular disease-related deaths dropped by 65% between 1968 and 2006. Heart disease, however, remains the most common cause of death, and there are pockets of the U.S. as well as certain groups of people in which the risk for cardiovascular disease remains high. According to the American Heart Association, based on 2006 data, more than 81 million people in the U.S. have one or more forms of cardiovascular disease; more than 73 million have high blood pressure.

Researchers have questioned whether socioeconomic factors play a role in cardiovascular disease risk and why disparities in cardiovascular disease rates exist between geographical regions and groups of people. Levine and her colleagues note that high blood pressure may account for up to 44% of the cardiovascular disease disparity between whites and African-Americans.

“Where you live, your race, and your gender strongly influence your risk of developing high blood pressure as you move from young adulthood into middle age -- and hypertension is a major risk factor for heart disease and stroke,” Levine says in a news release.  “The gaps may be widening, particularly for blacks. The reasons for the variations are not clear.” 

Until more is known, Levine says, “People at higher risk can benefit from close monitoring of their blood pressure and paying attention to risk factors such as obesity and [lack of] physical activity.”