Arterial Stiffness Assessed by Digital Volume Pulse Correlates With Comorbidity in Patients With ESRD

Background: Digital volume pulse (DVP), a noninvasive method for indirect assessment of arterial stiffness, was not tested previously in patients with end-stage renal disease (ESRD). Therefore, we compared the DVP-derived stiffness index (SIDVP) with aortic pulse wave velocity (PWV) determined by means of Doppler ultrasonography in 2 groups of patients with ESRD and analyzed the correlation between SIDVP and comorbidity. Methods: Photoplethysmography was performed on the index finger of the dominant hand or the hand from the nonfistula arm in 49 renal transplant (TX) recipients and 48 hemodialysis (HD) patients. Pulse curves were analyzed with computer assistance. Comorbidity was assessed by using an established index. Results: The intrasubject variability of SIDVP was 5.7%. SIDVP and aortic PWV values correlated significantly (r = 0.66; P = 0.001) in patients with ESRD. SIDVP could not be assessed reliably in 25% and 6% of HD patients and TX recipients, respectively. Multivariate regression analyses showed that SIDVP increased with age in both HD patients and TX recipients (r = 0.61; P < 0.001) and with systolic blood pressure (r = 0.53; P < 0.025), mean arterial pressure (r = 0.47; P < 0.05), and pulse pressure (r = 0.52; P = 0.02) in TX recipients. Severity of comorbid status was associated highly with individual residuals of age-adjusted SIDVP in HD patients and TX recipients (P < 0.001). Conclusion: DVP allows the measurement of arterial stiffness in most, but not all, patients with ESRD. SIDVP values correlate with comorbidity in HD patients and TX recipients.