Lower Pulse Pressure Hikes MortalityReduced mean arterial pressure (MAP) and pulse pressure (PP) are associated with increased mortality in hemodialysis patients, according to a study.
“Although low or normal PP reflects good vascular health in the normal population, PP is also a function of cardiac ejection characteristics and so may be reduced in patients with failing ventricles.” said lead investigator Mark Rohrscheib, MD, assistant professor of internal medicine in the department of nephrology at the University of New Mexico Health Science Center in Albuquerque.
Since most incident hemodialysis patients have left ventricular hypertrophy, a marker of reduced vascular compliance, and since arteriosclerosis accelerates in hemodial-ysis, it's most likely that the high mortality in our patients with low PP's is explained by left ventricular failure overriding the effect of stiff vessels.”The findings, from a study of 16,959 hemodialysis patients (8,088 women, 8,871 men) from centers across the United States, suggest that nephrologists may need to closely monitor hemodialysis patients with normal BP because patients in the lower range of normal may be at increased mortality risk.
In the study, 39% of patients were aged 45-64 years; 16% were younger and 45% were older. The study population had 6,211 deaths, of which 2,630 were cardiovascular. Increases in both MAP and PP were associated with decreased mortality. Compared with a MAP of 95-99 mm Hg, all lower values were associated with increased mortality. At each level of MAP, a decrease in PP also was associated with an elevated death risk.