Cardiovascular risk assessment using pulse pressure in the First National Health and Nutrition Examination Survey (NHANES I)

Increased stiffness of the conduit arteries has been associated with increa sed risk of death and cardiovascular death in a number of populations. None of these populations, however, are fully representative of the US populati on. The cohort examined in the First National Health and Nutrition Examinat ion Survey (NHANES I) that was free of overt cardiovascular disease was sel ected to be representative of the US population. We assessed and quantified the increased risk of death associated with elevated pulse pressure in thi s population. A cohort of 5771 subjects from NHANES I was used to determine the value of adding pulse pressure to standard cardiovascular disease risk factors for assessment of the risk of death during a mean follow-up period of 16.5 years. Analyses were performed by use of the SUDAAN statistical pa ckage for performing Cox proportional regression, logistic regression, and other standard methods in complex, weighted samples. Pulse pressure increas ed with increasing age, body mass index, cholesterol level, and mean arteri al pressure. With increasing pulse pressure, the percentage of cigarette sm okers decreased and the percentage of diabetics increased. Despite these as sociations with known risk factors, pulse pressure was independently predic tive of an increased risk of death from cardiovascular disease, coronary he art disease, and all-cause mortality. It provides independent prognostic in formation beyond that provided by known risk factors that were evaluated in this study, including the Sixth Joint National Committee on Prevention, De tection, Evaluation, and Treatment of High Blood Pressure hypertension clas sification. A 10 mm Hg increase in pulse pressure in persons 25 to 45 of ag e was associated with a 26% increase in risk of cardiovascular death (95% c onfidence interval [CI], 5 to 50) and with an 10% increase (95% CI, 2 to 19 ) in persons 46 to 77 years of age. In a cohort designed to be representati ve of the US population, elevated pulse pressure has been shown to provide independent prognostic information. This variable may be a marker for the e xtent of vascular disease and may contribute to the occurrence of clinical events.