Cardiovascular Dysautonomia of Patients With End-Stage Renal Disease and Type I or Type II Diabetes

BACKGROUND: End-stage renal disease and diabetes mellitus are known to cause autonomic dysfunctions that are responsible for poor outcomes. Studies suggest that 24-hour heart rate variability with power spectral analysis is more sensitive to early changes in autonomic function than laboratory-evoked measures. OBJECTIVES: To evaluate cardiovascular autonomic function in patients (a) awaiting kidney or pancreas-kidney transplantation, (b) without diabetes (NonDM), (c) with Type I insulin dependent diabetes mellitus (IDDM), and (d) with Type II noninsulin dependent diabetes mellitus (NIDDM), and to compare the results of the laboratory-evoked cardiovascular autonomic tests with those from 24-hour heart rate variability monitoring with power spectral analysis. METHOD: This cross-sectional study examined autonomic function in prekidney transplant patients with and without diabetes (N=96), comparing laboratory-evoked measures to 24-hour measures. RESULTS: The nondiabetic group had a normal change in heart rate with deep breathing, Valsalva ratio, and change in systolic blood pressure with tilt. Both diabetic groups had poorer values for all measures of heart rate variability; demonstrated abnormal changes in heart rate with deep breathing and borderline Valsalva ratios; demonstrated a greater decrease in circadian rhythmicity; and had lower SDNNS, pNN50s, and rMSSDs than the nondiabetic group. CONCLUSIONS: Results showed that 24-hour measures are more sensitive, that patients with end-stage renal disease and diabetes regardless of type experience significantly poorer function than do patients without diabetes, and that these values approach those associated with sudden cardiac death.