#2599 LONG-TERM LONGITUDINAL CHANGES OF PULSE WAVE VELOCITY AND THEIR ASSOCIATION TO CARDIOVASCULAR RISK FACTORS IN MAINTENANCE HEMODIALYSIS PATIENTS
Authors: Lattermann Moritz , Matschkal Julia , Braunisch Matthias , Wassertheurer Siegfried , Mayer Christopher , Guenthner Roman , Heemann Uwe , Schmaderer Christoph 
Published: June 2023

Abstract

Background and Aims
The incidence of end-stage renal disease (ESRD) is increasing worldwide. The mortality rate in this patient cohort remains unacceptably high. The WHO estimates ESRD as one of the ten global causes of premature death. Approximately half of all death cases are due to cardiovascular complications. A main cardiovascular risk factor is enhanced arterial stiffness. The measurement of pulse wave velocity (PWV) for evaluation of progressive atherosclerosis is known to be an independent risk predictor for cardiovascular and all-cause mortality in chronic dialysis patients.

Method
The study cohort contains patients from the “Risk stratification in end-stage renal disease - the ISAR study”, a multicenter prospective longitudinal observatory cohort study. A total of 105 patients on maintenance hemodialysis were examined and followed-up for up to 72 months. Pulse wave velocity was obtained by the Mobil-O-Graph 24h PWA Monitor device at baseline and follow-up. We assessed the PWV change over time and correlated PWV with known cardiovascular risk factors using Pearson correlation coefficient adjusting for age. Longitudinal changes were examined using t-tests for paired and independent samples.

Results
Patients had a median age of 61,2 years (IQR 23,2), 36 (34%) were female. Median baseline dialysis vintage was 105 months (IQR 71), and median adapted Charlson Comorbidity Index 2 (IQR 3). During a median follow-up of 74,1 months there was a significant increase in PWV from baseline (9,25 m/s) to 6YFU (10,18 m/s, p = &lt;0,001), a delta-PWV of 0,92 m/s, appropriate to a yearly change of 0,15 m/s. Patients with hypertension had a significant higher PWV (10,47 m/s) than those with normal blood pressure (8,91 m/s, p = 0,034). The Pearson correlation coefficient analysis showed after adjustment for age a significant correlation between blood pressure and both 6YFU-PWV (systolic r = 0,89 diastolic r = 0,62, p = &lt;0,001) and delta-PWV (systolic r = 0,71 diastolic 0,48, p = &lt;0,001). Additionally, after adjustment for age delta-PWV correlated with LDL-cholesterol (r = 0,27, p = 0,023). Neither 6YFU-PWV nor delta-PWV showed significant associations to other traditional cardiovascular risk factors such as diabetes, high cholesterol or obesity.

Conclusion
In this cohort, we found a longitudinal increase of pulse wave velocity over 6 years. However, the average change in PWV per year was significantly lower in our cohort compared to other studies with a shorter observation period. A main reason might be the long follow-up time, with the occurrence of several deaths in the primary cohort of the ISAR-Study before reaching the follow-up point and therefore including more younger and possibly healthier patients. Nevertheless, in this cohort blood pressure in contrast to diabetes, high cholesterol or obesity was a primary factor in the change of PWV. The reasons for the deceleration of cardiovascular and mortality risk after a long term in this sub cohort remains unclear and requires further investigation.