Individuals with diagnosed hypertension in the United States appear to have lower blood pressure readings and better hypertension control than patients in five Western European countries, according to a report in the January 22 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Hypertension (high blood pressure) affects many individuals and is a strong risk factor for cardiovascular disease, according to background information in the article. Studies suggest that hypertension is widely under-diagnosed and under-treated in the United States and Europe. Guidelines regarding the blood pressure at which treatment should begin differ in various countries, but tend to be more aggressive in the United States.
Y. Richard Wang, M.D., Ph.D., of Temple University Hospital and University of Pennsylvania, Philadelphia, and colleagues analyzed data from a survey of patients with hypertension visiting 291 cardiologists and 1,284 primary care physicians in the United States and five Western European countries: France, Germany, Italy, Spain and the United Kingdom. In 2004, the physicians in the survey were randomly selected, and those who agreed to participate completed two-page diaries for 15 cardiovascular patients. Information collected included patient characteristics, initial blood pressure level before treatment, any co-occurring diseases and the use of seven types of antihypertensive drugs.
Among the total of 21,053 patients from all six countries, 53 percent were male, 23 percent had diabetes and the average age was 65 years. At least 92 percent of patients with hypertension in each country were receiving medication for high blood pressure. The initial blood pressure level before treatment was available for 61 percent to 80 percent of patients per country and was lowest in the United States (average of 161/94 millimeters of mercury, vs. an average of 167 to 173/96 to 99 in Europe). The most recent blood pressure reading was also lower in the United States than in any other country (average of 134/79 millimeters of mercury, vs. an average of 139 to 144/80 to 84 millimeters of mercury in Europe). Only 65 percent of U.S. patients had an initial pre-treatment blood pressure level of 160/100 millimeters of mercury or higher, compared with 81 to 90 percent of European patients.
"The rate of hypertension control (latest blood pressure level, 140/90 millimeters of mercury or lower) was highest in the United States (63 percent vs. 31 percent to 46 percent of patients across European countries)," the authors write. "In addition, of the 11,969 patients with inadequately controlled hypertension, the United States had the highest percentage of patients receiving any medication increase during the visit (38 percent vs. 15 percent to 28 percent across European countries)." The use of medications known as thiazides was similar across countries (29 percent to 31 percent), but the use of other drug classes varied by country, and the use of combination drug therapy was highest in the United States (64 percent vs. 44 percent to 59 percent in Europe).
"Together, our findings suggest that better hypertension control in the United States may be explained by lower treatment thresholds and more intensive treatment, both of which are consistent with the more aggressive treatment guidelines in the United States compared with the other countries examined," the authors conclude.
(Arch Intern Med. 2007;167:141-147. Available pre-embargo to the media at www.jamamedia.org.)
Editor's Note: This study was supported by the MacLean Center for Clinical Medical Ethics, a grant from the National Institute of Aging and a grant from the Agency for Healthcare Research and Quality. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
Journal
Archives of Internal Medicine