Decreased b-Cell Function is Associated with Cardiovascular Autonomic Neuropathy in Chinese Patients Newly Diagnosed with Type 2 Diabetes

摘要

The influence of b-cell function on cardiovascular autonomic neuropathy(CAN), an important diabetesrelated complication, is still unclear. In this study, we aimed to investigate the association between residual b-cell function and CAN in patients newly diagnosed with type 2 diabetes. We enrolled 90 newly-diagnosed type 2 diabetic patients and 37 participants with normal glucose tolerance as controls. The patients were divided into a CAN? group(diabetic patients with CAN, n = 20) and a CAN-group(diabetic patients without CAN, n = 70) according to the standard Ewing battery of tests. Fasting and postprandial plasma glucose, insulin, and C-peptide were measured.Homeostasis model assessment-beta cells(HOMA-B) and HOMA-insulin resistance(IR) were calculated. The prevalence of CAN in this population was 22.2%. Compared with the CAN-group, the CAN? group had significantly lower fasting plasma insulin(6.60 ± 4.39 vs 10.45 ± 7.82 l/L, P = 0.029), fasting C-peptide(0.51 ± 0.20 vs0.82 ± 0.51 nmol/L, P = 0.004), and HOMA-B(21.44 ± 17.06 vs 44.17 ± 38.49, P = 0.002). Fasting C-peptide was correlated with the Valsalva ratio(r = 0.24, P = 0.043) and the 30:15 test(r = 0.26,P = 0.023). Further analysis showed that fasting C-peptide(OR: 0.041, 95% CI 0.003–0.501, P = 0.012) and HOMAB(OR: 0.965, 95% CI 0.934–0.996, P = 0.028) were independently associated with cardiovascular autonomic nerve function in this population. The patients with fasting C-peptide values 0.67 nmol/L were more likely to have CAN than those with C-peptide levels C0.67 nmol/L(OR:6.00, 95% CI 1.815–19.830, P = 0.003). A high prevalence of CAN was found in patients with newly-diagnosed type 2 diabetes. Decreased b-cell function was closely associated with CAN in this population.