Correlations of cardiovascular autonomic neuropathy with urinary albumin excretion rate and cardiac function in patients with type 2 diabetes mellitus.

Background: The associations of cardiovascular autonomic neuropathy (CAN) with diabetic nephropathy and heart disease remain elusive. The aim of this study was to explore the correlations of CAN with urinary albumin excretion rate (UAER) and cardiac function in patients with type 2 diabetes mellitus (T2DM).

Methods: A total of 225 T2DM patients were assigned into CAN and non-CAN groups using cardiovascular reflex tests (CARTs). They were divided into macroalbuminuria, microalbuminuria and normoalbuminuria groups according to urinary albumin/creatinine ratio (UACR), or left ventricular diastolic dysfunction and normal groups based on left ventricular peak E/A velocity ratio (E/A). The correlations of CAN with albuminuria and left ventricular diastolic dysfunction, and the predictive values of UACR and E/A were analyzed.

Results: Compared with non-CAN group, CAN group had older age, longer T2DM duration, higher serum urine acid (SUA) level, UACR, systolic and diastolic pressure differences between supine and standing positions, and lower other CARTs parameters and E/A (P<0.001). Macroalbuminuria group had largest positional systolic and diastolic pressure differences, and lowest other CARTs parameters (P<0.001). Compared with normal group, left ventricular diastolic dysfunction group had larger positional systolic and diastolic pressure differences, and lower other CARTs parameters (P<0.001). CAN in T2DM patients was positively correlated with albuminuria and left ventricular diastolic dysfunction (P<0.001). Age, SUA, UACR and E/A were independent predictive factors (P=0.031, P=0.005, P<0.001, P<0.001). UACR and E/A had high predictive values.

Conclusions: In T2DM patients, CAN is positively correlated with declined UAER and cardiac function. UACR and E/A have high predictive values.