Hypertension, But not "Prehypertension," Increases Stroke Risk -- and Should Combination Therapy Include a Calcium Antagonist?

March 16, 2004

In This Article

Global Prevalence of Hypertension May Be Close to 30%

A review of recent community-based studies on the prevalence of hypertension in different regions of the world conducted by researchers from Tulane University (New Orleans, Louisiana) has concluded that the true global prevalence of hypertension is approximately 30%.[19] The 41 studies selected for the review were all cross-sectional surveys that included descriptions of blood pressure measurement methods and defined hypertension as an average blood pressure of ≥ 140/90 mm Hg and/or the use of antihypertensive medications. Ten studies that provided information on selected aspects of hypertension prevalence were also included. All these studies were published between January 1980 and July 2003, in English or other languages.

The review found that the prevalence of hypertension varies widely around the world. The lowest rate (3.4%) was recorded in rural Indian men, and the highest (72.5%) in Polish women. In economically developed countries, the prevalence of hypertension is 20% to 50%. In the United States, it has been calculated as 27.1% in men and 30.1% in women, with similar rates in Canada. In Western Europe, rates tended to be higher than in North America. National studies from Latin America have estimated that about one third of the population have hypertension. In China, almost 130 million people aged 35-74 years are estimated to be hypertensive. The highest prevalence in Sub-Saharan Africa has been reported in urban Zimbabwe, which has rates close to those in economically developed countries.

Countries differ as to whether or not rates are similar in urban vs rural areas; studies in Cameroon, Egypt, Korea, Paraguay, Spain, and Thailand showed higher rates in urban areas. The prevalence of hypertension has been reported as higher in blacks than in whites in the United States and, to a lesser extent, in Cuba. In South Africa, however, white men have a higher prevalence of hypertension than black men, although the situation is reversed in women.

The studies showed that over the past decade, the prevalence of hypertension has remained stable or decreased in economically developed countries, but increased in economically developing countries. The most recent NHANES survey, however, reported that the prevalence of hypertension in the United States is increasing.[20] The authors who conducted this survey reported that levels of hypertension awareness, treatment, and control also vary throughout the world, tending to increase in China, the United States, and Western Europe. The authors of this review, published in JAMA, stress the low rates of hypertension awareness and diagnosis and the inadequacy of treatment among people who are diagnosed with hypertension. They believe that their data should provide an impetus for population-level approaches to the prevention and treatment of hypertension worldwide.