Baroreflex Sensitivity and Hemodynamic Parameters at Rest and in Response to Physical and Mental Stress: A Comparative Study of Patients Undergoing Different Dialysis Modalities.

Introduction Cardiac arrhythmias are the leading mortal cause of end-stage kidney disease (ESKD), and autonomic dysfunction plays a predominant role. This is the first study to compare baroreflex sensitivity (BRS) and hemodynamic responses at rest and after mental and physical stimulation maneuvers between hemodialysis (HD) and peritoneal dialysis (PD) patients. Methods A total of 68 ESKD patients (34 HD and 34 PD, matched for age, sex, and dialysis vintage) were included. Continuous recordings from Finometer-PRO at rest and during mental arithmetic, orthostatic, and handgrip exercise tests were used for the calculation of BRS and hemodynamic responses in each individual. Results The two groups were similar in terms of age, sex, dialysis vintage, and major comorbidities. BRS during mental (HD: 3.59±2.62 vs. PD: 5.50±9.40 ms/mmHg, p=0.280) and physical stress tests (orthostatic: HD: 3.23±2.42 vs. PD: 2.07±2.69 ms/mmHg, p=0.777) was similar between HD and PD patients. During the mental test, both groups presented increases in systolic (SBP) and diastolic blood pressure (DBP) levels compared to rest (SBP HD: 156.3±27.7 vs. 142.7±20.0 mmHg, p<0.05; PD: 158.0±25.6 vs. 143.1±23.6 mmHg, p<0.05), but without significant between-group differences (p=0.853/p=0.611). Similarly, no significant between-group differences were noted in the other hemodynamic parameters. Mean SBP levels during the orthostatic test were significantly decreased compared to rest in both groups (HD: 135.4±26.8 vs. 142.2 ±20.1 mmHg; p<0.05; PD 135.3±21.9 vs. 143.1±23.6 mmHg; p<0.05), but the overall response was not different between groups (p=0.937). Finally, the hemodynamic responses during handgrip exercise and recovery did not differ between HD and PD. Conclusions BRS and hemodynamic responses to mental and physical stress tests were similar between HD and PD patients, suggesting that the function of the autonomic nervous system (ANS) in ESKD is not affected by dialysis modality.