Heart Rate Variability in Patients with Diabetic Nephropathy

Kidney 09/2009; 18(5):241-246. DOI: 10.1007/s00596-009-0094-1


BackgroundPatients with diabetic nephropathy are likely to have neurological complications including cardiovascular autonomic dysfunction,
which is related to increased risk of mortality and it probably had an earlier onset and may precede the appearance of autonomic
symptoms. The aim of this study was to assess cardiovascular autonomic functions by using heart rate variability analysis and its relationship
with left ventricular function in type 2 diabetic patients with and without nephropathy.

Materials and MethodsThis study was conducted on 45 diabetic patients, 15 without nephropathy, 15 with nephropathy and 15 diabetic nephropathy
on hemodialysis, as well as 15 age- and sex-matched healthy controls. All of them were subjected to analysis of heart rate
variability (HRV) by Holter ECG, Echocardiography, and analysis of the lipid profile.

ResultsAll time domain and frequency domain measures of HRV were significantly reduced in diabetic patients with and without nephropathy
compared to healthy controls (p < 0.0001). There was a significant decrease in ejection fraction (EF) and increase in left ventricular mass index (LVMI)
in diabetic patients with and without nephropathy compared to healthy controls (p < 0.0001). Also there was a significant increase in cholesterol, triglycerides and LDL with significant decrease in HDL in
diabetic patients with and without nephropathy compared to healthy controls (p < 0.0001).

ConclusionCardiac autonomic dysfunction (as manifested by decreased HRV) was demonstrated in diabetic patients and its degree was enhanced
in patients with nephropathy than in those without.

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