Pulse pressure (the difference between systolic and diastolic blood pressures) rises with age as a result of arterial stiffening, and arterial stiffness is a known risk factor for cardiovascular disease. To evaluate whether an increased pulse pressure could serve as a predictor of congestive heart failure in the elderly, Chae and colleagues conducted a prospective cohort study of the possible relationship between increased pulse pressure and the occurrence of congestive heart failure in 1,621 elderly persons.
The study population included participants in the National Institute on Aging's Established Populations for Epidemiologic Studies of the Elderly. None showed evidence of congestive heart failure at the time of entry into the study. The mean age of the study population was 77.9 years, and 66.1 percent of the group were women. At baseline, 54.6 percent had been diagnosed with hypertension. Diabetes was present at baseline in 19.3 percent, coronary heart disease in 10.3 percent, atrial fibrillation in 2.8 percent and valvular heart disease in 1.8 percent. The development of congestive heart failure was the primary end point, and it was subsequently diagnosed in 221 of the participants during the 3.8 years of follow-up.
Blood pressure values were obtained by measuring the blood pressure three times at 30-second intervals and using the average of the three values. The mean arterial pressure was calculated by using the following formula:
Gender, the presence of coronary heart disease or atrial fibrillation, and smoking history were not related to an increased pulse pressure. An increased pulse pressure, however, was related to age, use of antihypertensive medications and presence of diabetes mellitus. The risk of congestive heart failure was linearly and significantly related to the pulse pressure. There was an age-adjusted 17 percent increase in the risk of congestive heart failure with every 10 mm Hg rise in the pulse presure. Those who had the highest tertile pulse pressures had a 75 percent increased risk of congestive heart failure compared with those whose pulse pressures were in the lowest tertile. The mean arterial pressure was not associated with an increased risk of congestive heart failure.
The authors conclude that pulse pressure is an independent predictor of the risk of congestive heart failure. Knowing that a patient is at increased risk of congestive heart failure is important because the risk may be modified by drug therapy with angiotensinconverting enzyme inhibitors, which may cause left ventricular hypertrophy regression, and nitrates, which may improve arterial distensibility, and by other therapeutic interventions, such as a low-salt diet.