The prevalence of diabetic autonomic neuropathy indicated by abnormal R-R interval variation.

The variation in R-R interval in ECG has been reported to decrease in diabetics with autonomic neuropathy. To investigate the diagnostic value of heart rate monitoring and the prevalence of diabetic autonomic neuropathy, R-R interval variations (CVs) were measured, and the relationships between CV and MCV, FCV, SCV, retinopathy, nephropathy, peripheral neuropathy, and duration of diabetes were investigated. 70 diabetics aged 19 approximately 74 were studied. A total of 100 consecutive R-R intervals on ECG were analyzed by computer. 16 patients (22.8%) of 70 had one or more symptoms of autonomic neuropathy, while the prevalence of diabetic autonomic neuropathy indicated by abnormally low CV was 41.4%. Diabetics with retinopathy, nephropathy or peripheral neuropathy had significantly lower CVs than diabetics without these complications (p less than 0.01). The correlation coefficients for CV and duration of diabetes, and CV and SCV were -0.69 and 0.57 respectively (p less than 0.01). CV (%) of R-R interval was a useful parameter for the determination of diabetic autonomic neuropathy and our results showed that autonomic nerve damage was more prevalent than were symptoms of autonomic neuropathy.