Association of impaired baroreflex sensitivity and increased arterial stiffness in peritoneal dialysis patients.
BACKGROUND
Peritoneal dialysis patients have high cardiovascular morbidity and mortality. The underlying mechanism of cardiovascular dysfunction remains unclear. Large arterial stiffness in chronic kidney disease (CKD) patients leads to increase in pulse wave velocity (PWV) and decrease in baroreflex sensitivity (BRS). Impairment in baroreflex function could be attributed to the alteration in mechanical properties of large vessels due to arterial remodeling observed in these patients. The present study was designed to study the association of BRS and PWV in peritoneal dialysis (PD) patients.


METHODS
42 CKD patients (21--without dialysis and 21--on PD) and 25 healthy controls were recruited in this study. BRS was determined by spontaneous sequence method. Short-term heart rate variability (HRV) and blood pressure variability (BPV) were assessed using power spectrum analysis of RR intervals and systolic blood pressure by time domain and frequency domain analysis. Arterial stiffness indices were assessed by carotid-femoral PWV using Sphygmocor Vx device (AtCor Medical, Australia).


RESULTS
CKD patients had significantly high PWV and low BRS as compared to healthy controls. PWV had a significant negative correlation with BRS in CKD patients (Spearman r = -0.7049, P < 0.0001; BRS-Systolic BP). On subgroup analysis, PWV was higher with lower BRS in CKD patients on peritoneal dialysis (CKD-PD) as compared to those not on dialysis (CKD-ND). Negative relationship between PWV and BRS was found in both the groups. In addition, BRS was found to have a positive correlation with HRV in CKD patients as well as both the subgroups.


CONCLUSIONS
Reduction in BRS is strongly associated with increase in PWV in PD patients. Large arterial stiffness probably explains this simultaneous impairment in baroreflex functioning and increase in pulse wave velocity observed in these patients. CKD patients are characterized by poor hemodynamic profile (low BRS, high PWV, and low HRV), and peritoneal dialysis patients had further worsened profile as compared to non-dialysis group.
Department of Nephrology, All India Institute of Medical Sciences, New Delhi, India.
Amit
A
Gupta
Department of Physiology, All India Institute of Medical Sciences, New Delhi, India.
Gaurav
G
Jain
Department of Physiology, All India Institute of Medical Sciences, New Delhi, India.
Manpreet
M
Kaur
Department of Physiology, All India Institute of Medical Sciences, New Delhi, India.
Ashok Kumar
AK
Jaryal
Department of Physiology, All India Institute of Medical Sciences, New Delhi, India.
Kishore Kumar
KK
Deepak
Department of Nephrology, All India Institute of Medical Sciences, New Delhi, India. dmbhowmik@yahoo.co.in.
Dipankar
D
Bhowmik
Department of Nephrology, All India Institute of Medical Sciences, New Delhi, India.
Sanjay Kumar
SK
Agarwal
D000328:Adult; D017704:Baroreflex; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis; D063177:Pulse Wave Analysis; D059289:Vascular Stiffness
Baroreflex sensitivity; Blood pressure variability; Chronic kidney disease; Heart rate variability; Peritoneal dialysis; Pulse wave velocity