Study of the Central and Peripheral Autonomic Function in Short Evolutions Type 2 Diabetes and it’s Risk Categories

Abstract

Objective: Early detection of Diabetic Autonomic Neuropathy (DAN) could help prevent serious complications and mortality associated with this condition in type 2 diabetes. We aimed to determine the prevalence of Sudomotor Autonomic Dysfunction, Cardiac Autonomic Dysfunction (SAD, CAD) in the early stages of glucose metabolism alterations, ranging from risk categories for type 2 diabetes (prediabetes) to recently established type 2 diabetes. Research Design and Methods: It is a longitudinal, prospective and observational study (population consisting in 30 control subjects, 30 patients with increased risk for type 2 diabetes and 30 patients with type 2 diabetes ≤8 years of evolution. Study was carried out by designing a modified battery of Ewing. To study autonomic: resting Heart Rate (HR), deep inspiration, controlled breathing, 30/15, Valsalva maneuver, Sustained handgrip test (SHGT) and prolonged QTc indexes) and to study sudomotor: measurement of the Skin Conductance Response (SCR) deep inspiration, controlled breathing, standing to orthostasis, Valsalva maneuver and SHGT. The ECG and the Electrodermal response signal (EDR) was recorded while the patients execute the tests. Results: Results were statistically analyzed by taking into account the group the patients belonged to, their anthropometric variables (directly measured) and their results from blood tests. Obtained results allowed us to determine the order in which every autonomic index passes from normal to abnormal and the corresponding nerve fibers involved. Cardiac autonomic variables: resting HR: it is average value increases as the dysglicaemia progressed, significant differences were only found between the control and the type 2 diabetes group (p=0.041). Deep inspiration index: significant differences were only found between the increased risk group and the type 2 diabetes group (p=0.047). 42.9% of the control subjects, 39.1% of the increased risk patients and 59.3% of type 2 diabetes presented anomalous values for this index.