Previous studies demonstrated that different parameters of arterial stiffness are related to cardiovascular mortality in hemodialysis patients. The relative prognostic value of these parameters has not previously been evaluated in one cohort.
Patients and methods: Carotid-femoral pulse wave velocity, carotid augmentation index, carotid pulse pressure and carotid-brachial pulse pressure amplification were measured in 98 patients before and after hemodialysis. Patients were followed for a median of 29 months (1-34) and the association of these parameters with cardiovascular mortality was assessed using log-rank tests and Cox proportional hazards regressions.
Results: During follow-up, 40 patients died (mortality rate 20.7/100 patient-year), of which 25 died of cardiovascular causes. Increasing pre- and postdialysis pulse wave velocity tertiles and decreasing predialysis pulse pressure amplification tertiles were significantly related to cardiovascular mortality (p-values are 0.012 and 0.011 for pre- and postdialysis pulse wave velocity, and <0.001 and 0,321 for pre- and postdialysis pulse pressure amplification, respectively). Neither the carotid augmentation index nor carotid pulse pressure was related to cardiovascular mortality. In the Cox-regression, the adjusted hazard ratios for 1 m/s higher pre- and postdialysis pulse wave velocity were 1.24 (1.07-1.44) and 1.17 (1.06-1.28), respectively. The hazard ratio for 10% lower predialysis pulse pressure amplification was 1.41 (1.03-1.92). When included in the same model, both predialysis pulse wave velocity and pulse pressure amplification remained significantly associated with cardiovascular mortality (relative risk: 1.23 [1.07-1.42] and 1.39 [1.02-1.89]).
Conclusion: Among different stiffness parameters, pulse wave velocity is consistently related to cardiovascular mortality, irrespective of the timing of measurement. Predialysis pulse pressure amplification seems to provide additional prognostic information.