July 20, 2004
Study Reveals High Burden of Peripheral Arterial Disease
High-risk groups, such as the elderly, current smokers, African-Americans and people with reduced kidney function, are at high risk for peripheral arterial disease (PAD), according to a study by researchers from the Johns Hopkins Bloomberg School of Public Health. The study provides nationally representative estimates for the prevalence of PAD and the first solid numbers on who is most affected by the disease in the general U.S. population. The study warns that PAD – the progressive narrowing of arteries in the lower extremities due to atherosclerosis – is a risk factor for cardiovascular disease and mortality. Common symptoms of PAD include cramping in the leg muscles when walking. The study, “Prevalence of and Risk Factors for Peripheral Arterial Disease in the United States,” is published in the July 19, 2004, rapid access online edition of Circulation: Journal of the American Heart Association.
Elizabeth Selvin, MPH, the study’s lead author and a PhD candidate in the School’s Department of Epidemiology, said, “The current recommendation is for only those people over the age of 50 who have diabetes to obtain screenings for PAD. Our study suggests that there are other high risk groups who might also be considered for screening.”
Data on ankle brachial blood pressure, a method for detecting PAD, for 2,174 people aged 40 and over were analyzed by the study authors. The data were obtained from the 1999-2000 National Health and Nutrition Examination Survey, which is an ongoing, cross-sectional survey of the civilian, non-institutionalized U.S. population.
The researchers found that PAD affects over 4 percent of adults age 40 and over, which is about 5 million people. Over 14 percent of adults 70 and over have PAD. In addition, African-Americans are more than twice as likely to have PAD as caucasians. Current smokers, diabetics and people with reduced kidney function are all at a greater risk of having PAD.
The researchers also noted that more than 95 percent of people with PAD had one or more traditional cardiovascular risk factors, such as hypertension, high cholesterol, smoking or diabetes. “The presence of PAD points to a high risk of coronary heart disease. People with PAD should have their cardiovascular risk factors treated aggressively,” Selvin said.
The authors said that people who are at high risk should discuss being screened for PAD with their physicians. According to Selvin, PAD can be diagnosed easily by taking blood pressure measurements in the arm and ankle, which is a simple, non-invasive procedure.
“Understanding who is most affected by this disease can help us understand what the implications of screening might be. Solid prevalence estimates of the burden of PAD in the United States are also important for policy makers when setting agendas for screening and allocating healthcare resources,” said Selvin.
The study’s lead author was supported by a training grant from the National Heart, Lung and Blood Institute.
Thomas P. Erlinger, MD, MPH, assistant professor in the Johns Hopkins Bloomberg School of Public Health Department of Epidemiology, co-authored the study.