Dynamic cerebral autoregulatory capacity is affected early in Type 2 diabetes

Authors:
Publisher website
Google Scholar
Abstract
Type 2 diabetes is associated with an increased risk of endothelial dysfunction and microvascular complications with impaired autoregulation of tissue perfusion. Both microvascular disease and cardiovascular autonomic neuropathy may affect cerebral autoregulation. In the present study, we tested the hypothesis that, in the absence of cardiovascular autonomic neuropathy, cerebral autoregulation is impaired in subjects with DM+ (Type 2 diabetes with microvascular complications) but intact in subjects with DM− (Type 2 diabetes without microvascular complications). Dynamic cerebral autoregulation and the steady-state cerebrovascular response to postural change were studied in subjects with DM+ and DM−, in the absence of cardiovascular autonomic neuropathy, and in CTRL (healthy control) subjects. The relationship between spontaneous changes in MCA Vmean (middle cerebral artery mean blood velocity) and MAP (mean arterial pressure) was evaluated using frequency domain analysis. In the low-frequency region (0.07–0.15 Hz), the phase lead of the MAP-to-MCA Vmean transfer function was 52±10 ° in CTRL subjects, reduced in subjects with DM− (40±6 °; PPVmean to postural change was comparable for all groups (−12±6% in CTRL subjects, −15±6% in subjects with DM− and −15±7% in subjects with DM+). HbA1c (glycated haemoglobin) and the duration of diabetes, but not blood pressure, were determinants of transfer function phase. In conclusion, dysfunction of dynamic cerebral autoregulation in subjects with Type 2 diabetes appears to be an early manifestation of microvascular disease prior to the clinical expression of diabetic nephropathy, retinopathy or cardiovascular autonomic neuropathy.

This publication has 47 references indexed in Scilit: