Reduced baroreflex effectiveness index in hypertensive patients with chronic renal failure.
BACKGROUND
Impaired arterial baroreflex function has been associated with an increased risk of ventricular arrhythmia and sudden death. This has also been suggested for patients with chronic renal failure (CRF) who are at high risk for cardiovascular morbidity. The aim of this study was to investigate the arterial baroreflex function in CRF patients with emphasis on analyzing the time during which the arterial baroreflex is active, the baroreflex effectiveness index (BEI).


METHODS
Beat-to-beat blood pressure (measured with Portapres) and electrocardiography were continuously registered during 30 min rest in 216 hypertensive CRF patients on hemodialysis (n=95), continuous ambulatory peritoneal dialysis (n=59), or conservative treatment (n=59). The spontaneous sequence method was used to calculate BRS and BEI. Age-matched healthy subjects (n=43) were examined for comparison.


RESULTS
The BRS was reduced by 51% and the BEI by 49% in CRF patients compared with healthy subjects (P<.001 for both). In addition, CRF patients with diabetes showed further reductions compared with patients without diabetes (15% reduction of BRS and 44% of BEI, P<.01 for both). The treatment modality for renal failure had no effect on BRS or BEI. In a multivariate linear regression analysis, age, body mass index, and systolic blood pressure were independent predictors of BRS, whereas age and diabetes were independent predictors of BEI in patients with CRF.


CONCLUSIONS
We conclude that BEI, which is markedly reduced in hypertensive patients with CRF, may convey information on arterial baroreflex function that is complementary to BRS.
Johansson
Mats
M
Department of Clinical Physiology, Sahlgrenska University Hospital, Göteborg, Sweden. m.johansson@medfak.gu.se
Gao
Sinsia A
SA
Friberg
Peter
P
Annerstedt
Marita
M
Bergström
Göran
G
Carlström
Jan
J
Ivarsson
Ted
T
Jensen
Gert
G
Ljungman
Susanne
S
Mathillas
Oivind
O
Nielsen
Finn-David
FD
Strömbom
Ulf
U
D000959:Antihypertensive Agents / Q000627:therapeutic use; D017704:Baroreflex / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology*; D007676:Kidney Failure, Chronic / Q000150:complications / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive; D006435:Renal Dialysis
D000959:Antihypertensive Agents