Around-the-clock ambulatory pulse pressure monitoring is a better predictor of adverse cardiovascular events than conventional office pulse pressure monitoring, especially in older patients with isolated systolic hypertension, according to an article in the October issue of the American Journal of Hypertension.

For the current analysis, investigators used the ambulatory blood pressure data of 808 patients enrolled in the Systolic Hypertension in Europe (Syst-Eur) Trial to determine whether ambulatory pulse pressure was a better predictor of adverse cardiovascular outcomes than ambulatory mean pressure, pulse pressure or mean pressure calculated from conventional blood pressure readings.

The eligible participants (311 men and 497 women) were at least 60 years old and had seated systolic blood pressures of 160 to 219 mm Hg, with diastolic pressure less than 95 mm Hg. Patients were assigned to either medication or placebo. The median follow-up was 4.4 years.

Investigators found that in the untreated older patients with systolic hypertension, higher ambulatory pulse pressure increased the risk of cardiovascular mortality and cardiovascular complications. Conventionally measured pulse pressure predicted only cardiovascular mortality.

The authors noted there was a 4 to 6 mm Hg reduction in conventional and ambulatory pulse pressures in those patients taking hypertension medication or medications. They also found 24-hour and nighttime ambulatory pulse pressure predicted cardiovascular outcome "over and beyond" pulse pressure calculated from conventional blood pressure measurements.

"Our observations are in line with the growing body of evidence proving that, especially in older people, pulse pressure measured by conventional sphygmomanometry is an independent risk factor," they said.

"The greater number of measurements, the absence of digit preference and observer bias, and the minimization of the white coat effect probably contributed to the predictive superiority of ambulatory over conventional pulse pressure," the investigators explained. "Furthermore, in keeping with established hemodynamic concepts, ambulatory pulse pressure may more accurately reflect the interplay between the heart and the central
arteries."

Journal editor Michael A. Weber, M.D., said "The study further confirms that pulse pressure is a powerful predictor of cardiovascular outcomes in the elderly. Ambulatory monitoring provides an important reproducible measurement and is especially valuable in
overcoming the white coat effect of physician measurement."

"In addition, the investigators confirmed the importance of monitoring isolated systolic blood pressure, especially in people aged 50 years and older," Weber said. "Systolic blood pressure increases with age and is often higher in women than in men. High systolic pressure is a strong warning sign for strokes and heart attacks."