Influence of Visceral Adiposity on Cardiovascular Autonomic Neuropathy in Patients with Type 2 Diabetes Mellitus

Background: The aim of this study was to investigate the influences of visceral adiposity on cardiovascular autonomic neuropathy (CAN) in patients with type 2 diabetes mellitus. Methods: Two hundred eleven patients with type 2 diabetes participated in this study. Anthropometric and metabolic parameters were measured, and the visceral fat area was assessed using computed tomography. CAN was diagnosed using a cardiovascular reflex test. We analyzed the correlation between the visceral fat area and each parameter in this test. Results: The mean age, body mass index (BMI), and duration of diabetes of the study population were 60 +/- 14 years (mean +/- standard deviation), 25.1 +/- 4.2 kg/m(2), and 12.3 +/- 8.9 years, respectively. The visceral fat area showed positive correlations with age, BMI, waist circumference, and subcutaneous fat area. There was no statistically significant difference in the cardiovascular reflex test outcome between genders. Univariate linear regression analysis showed that an increased visceral fat area diminished good heart rate response to a Valsalva maneuver (R-2=4.9%, P=0.013 in an unadjusted model), but only in women. This statistical association was preserved after adjusting for age and BMI (R-2=9.8%, P=0.0072). Conclusion: The results of this study suggest that visceral adiposity contributes to an autonomic imbalance to some degree, as demonstrated by the impaired cardiovascular reflex test among women with type 2 diabetes.