High blood pressure increased 30 percent over the last decade in the U.S.

The number of adults in the United States with high blood pressure increased 30 percent over the last decade (from 1988-94 to 1999-2000), according to a study published in today’s Hypertension: Journal of the American Heart Association.

The study found that at least 65 million Americans have hypertension, defined as blood pressure of 140/90 millimeters of mercury (mm Hg) or higher, using blood-pressure lowering medications, or having been told at least twice by a physician or other health professional that they had high blood pressure (medical history). By that definition, almost a third of U.S. adults have hypertension.

“The bottom line is that the estimated number of adults with high blood pressure has increased,” said Larry E. Fields, M.D., lead author of the study and senior executive advisor to the assistant secretary of the Department of Health and Human Services (DHHS).

“High blood pressure is a major risk factor for coronary heart disease, kidney failure, heart failure, stroke and other conditions. From a public and health professional perspective, it is important to be aware of high blood pressure, to have blood pressure checked regularly, and if blood pressure is elevated, to initiate appropriate counseling and treatment,” he said.

The findings came from an analysis of data from the U.S. Census Bureau and the 1999–2000 National Health and Nutrition Examination Survey (NHANES) IV, which included 4,531 people. The study was limited to people at least 18 years old. The new estimate is much higher compared to the previous NHANES report (16,351 participants from 1988-94) that estimated at least 50 million U.S. adults had high blood pressure.

Blood pressure values were based on three measurements that a physician took once in a mobile examination center.

Fields and his associates estimated that 59.2 million people had hypertension on the basis of blood pressure measurements or prescriptions for blood pressure medication. More than 6 million people had high blood pressure based on their medical history, resulting in an estimated total of 65.2 million hypertensive adults.

Reflecting the age-related association with high blood pressure, the number of people with hypertension was about 4.4 million in the 18–34 age group; 8 million in the 35–44 group; 12.7–12.8 million in the 45–54 and 55–64 age groups; 13.2 million in the 65–74 age group, and 14.1 million in the 75-and-older age group.

The 1999-2000 survey shows that 28.7 percent of women and 28.3 percent of men have high blood pressure. When prevalence was divided along racial/ethnic categories, non-Hispanic black Americans have the highest prevalence at 38.8 percent. High blood pressure is prevalent in 28.7 percent of the Mexican American population, and in 27.2 percent of the non-Hispanic white population.

The study did not specifically examine potential reasons for the increased prevalence of high blood pressure. However, the investigators cited the aging of the U.S. population and the growing proportion of overweight and obese Americans as potential major contributors. Older age, excess weight and lack of physical activity all increase the risk of hypertension.

The investigators hope increased awareness of the prevalence and health risks of high blood pressure will lead to better evaluation and treatment of the condition and to a greater focus on prevention.

“It has been demonstrated that interventions that center on health behavior, such as getting regular physical activity, controlling weight, and eating a nutritious diet that includes lots of fruits and vegetables and moderate amounts of salt, can reduce a person’s chances of developing high blood pressure,” said Fields, who is on leave as associate professor of medicine at Washington University in St. Louis.

Co-authors are Vicki L. Burt, ScM, R.N.; Jeffery A. Cutler, M.D., M.P.H.; Edward J. Roccella, Ph.D., M.P.H.; Paul Sorlie, Ph.D.; and Jeffery Hughes, M.P.H.