The association between cardiac autonomic neuropathy with metabolic and other factors in subjects with type 1 and type 2 diabetes.

BACKGROUND: Cardiac autonomic neuropathy (CAN) is a common diabetes complication associated with poor prognosis. This cross-sectional study aimed to examine for associations between CAN and metabolic and other parameters in patients with either type 1 (T1DM) or type 2 (T2DM) diabetes.

PATIENTS AND METHODS: A total of 600 patients (T1DM, n=200; T2DM, n=400) were recruited. Participants with overt nephropathy, macrovascular complications, and treated hypertension were excluded. CAN was diagnosed when two of the four classical autonomic function tests were abnormal.

RESULTS: CAN was diagnosed in 42.0% and in 44.3% of the participants with T1DM and T2DM, respectively. Multivariate logistic regression analysis demonstrated that, in T1DM, the odds [OR (95% confidence intervals)] of CAN increased with higher waist circumference [1.36 (1.01-2.02)], systolic blood pressure [1.16 (1.03-1.31)], hypertension [1.19 (1.03-2.67)], smoking [1.10 (1.12-1.40], fasting glucose [1.01 (1.00-1.01)], HbA(1c) [1.69 (1.07-2.76)], pubertal diabetes onset [1.08 (1.03-1.24)], LDL cholesterol [1.01(1.00-1.02)], triglycerides [1.58 (1.24-1.48)], retinopathy [1.13 (1.04-1.41)], peripheral neuropathy [2.53 (1.07-2.99)], glomerular filtration rate [0.93 (0.87-0.99)], and microalbuminuria [1.24 (1.12-1.36)]. The same analysis in T2DM demonstrated that the odds of CAN increased with higher waist circumference [1.08 (1.00-1.39)], systolic blood pressure [1.06 (1.02-1.12)], hypertension [1.50 (1.24-2.03)], smoking [1.22 (1.14-1.49)], diabetes duration [1.20 (1.09-1.34)], fasting glucose [1.21 (1.12-1.31)], HbA(1c) [1.25 (1.08-1.45)], LDL cholesterol [1.35 (1.04-1.75)], triglycerides [1.30 (1.00-1.68)], retinopathy [1.24 (1.16-1.35)], peripheral neuropathy [1.79 (1.07-2.01)], glomerular filtration rate [0.96 (0.95-0.97)], and microalbuminuria [1.20 (1.14-1.36)].

CONCLUSIONS: CAN is common in diabetes and is associated with modifiable factors including central fat distribution, hypertension, dyslipidemia, worse diabetes control, and smoking, and with the other microvascular complications of diabetes. Our findings emphasize the need for a multifactorial intervention for the prevention of CAN.