Clinical Study On Diabetic Autonomic Neuropathy

[Objective] :To evaluate autonomic nervous function in type 2 diabetes mellitus patients through the study of symptoms of diabetic autonomic neuropathy(DAN), cardiovascular reflex tests(CRT) and heart rate variability(HRV).[Methods] :According to evaluation of symptoms of DAN, 50 cases with type 2 diabetetes mellitus were divided into DANS-group(patients with symptoms of DAN)and the DANS+ group (patients without symptoms of DAN);According to the results of CRT, diabetic patients were divided into CRT" group(patients with scores of CRT<2) and CRT≥ group(patients with scores of CRT≥2).HRV were analysized in all the diabetic patients and 25 controls. [Results]:1 The duration of diabetic history in DANS+ group was longer than in DANS" group. And the HbA1c level was higher in DANS+ group. 2. The overall positive rate of CRT in 50 diabetic patients was 48%. 3. Compared with control group, the indices of frequency-domain HRV [LF(nor)10, HF(nor)10, LF(nor)4, HF(nor)4] were markedly reduced in both DANS" group and DANS+ group,especially in DANS+ group. 4. Compared with control group, the indices of frequency-domain HRV[HF(nor)10,LF(nor)4, HF(nor)4] were markedly reduced and LF/HF(nor)4 was higher in DANS" group. The indices of frequency-domain HRV [LF(nor)10,HF(nor)10,LF(nor)4,HF(nor)4] were also lower significantly in DANS≥ group than in DANS" group.5. In diabetic patients indices of frequency-domain HRV were inservely correlated with the duration of diabetic history, the HbA1c level and the CRT results. But they were no correlated with gender, age, free blood glucose, fructosamine and symptoms of DAN. [Conclusion] :1.The indices of frequency-domain HRV are markedly reduced in type 2 diabetes mellitus patients without symptoms of DAN and the scores of CRT≥2. With the appearance of symptoms of DAN and increaseing CRT scores, they are more reduced. 2, DAN is a progressive process. In diabetic patients the longer the duration of diabetic history and the higher of the level of HbA1c are, the lower the indices of frequency-domain HRV are.