Association between pulse pressure and mortality in patients undergoing peritoneal dialysis

Pulse pressure has been shown to be associated with adverse outcomes in the general population and in patients on hemodialysis (HD). However, the significance of pulse pressure has not been studied in peritoneal dialysis (PD) patients. This study examined the association between pulse pressure and mortality in patients undergoing chronic PD.

All patients aged 18 years or older that commenced PD between 1 January 2000 and 31 December 2005 at the University Health Network, Toronto, were included. The association between pulse pressure and mortality was assessed using the Cox proportional hazards model.

A total of 306 patients were included in the study. Mean pulse pressure of the study cohort was 56.8 +/- 17.8 mmHg. Age and diabetes were significant predictors of elevated pulse pressure (p < 0.001). After adjusting for the level of systolic blood pressure and other demographic and clinical parameters, multivariable Cox proportional hazards modeling showed a direct and consistent association between pulse pressure and death risk. Each increment of 1 mmHg in pulse pressure was associated with a 2.7% increased hazard of all-cause death [95% confidence interval (CI) 1.001 - 1.054, p = 0.039] and a 4.1% increase in risk for cardiovascular mortality (hazard ratio 1.041, 95% CI 1.003 - 1.081; p = 0.035).

Elevated pulse pressure is associated with an increased risk of all-cause and cardiovascular death in patients on PD. Recognition of this characteristic as an important predictor of mortality suggests that one goal of antihypertensive therapy in PD patients should be to decrease elevated pulse pressure.