Effect of glycemic status on carotid artery stiffness and cerebral blood flow

Increase in arterial stiffness with age and/or disease increases risk for cardiovascular events such as myocardial infarction and stroke. The brain is a high flow organ, particularly susceptible to hemodynamic pulsatility. Diabetes is a group of chronic diseases characterized by hyperglycemia. The injurious effects of hyperglycemia are classified into macrovascular complications (coronary artery disease, peripheral arterial disease, and stroke) and microvascular complications (diabetic nephropathy, neuropathy, and retinopathy). It is important for physicians to understand the relationship between diabetes and vascular disease.

Thus, this study was undertaken to test the hypothesis that elevated blood glucose levels in diabetes mellitus increases arterial stiffness, which further leads to increase in carotid pressure/flow pulsatility and CBFv pulsatility.

Fifty six (56) patients with type 2 DM and 60 age-matched healthy volunteers were prospectively enrolled. Arterial stiffness was measured using non-invasive PC based cardiovascular risk analysis system (Periscope TM). The TCD examination was performed by using Trans-Cranial Doppler.

CFPWV of diabetic group showed significantly higher mean values (Group 1=931.00±215.98cm\s, Group 2=1241±152.03 cm\s) than control subjects (758±151.82 cm\s). CFPWV was significantly (p<0.05) increased among two diabetic groups. Glycosylated Hemoglobin was most significantly correlated to CFPWV (r=1.00, p<0.05) followed by weak correlation between CFPWV and PI (r=0.2, p>0.05).

Type 2 Diabetes Mellitus (T2DM) increases carotid artery stiffness and pressure pulsatility index, without affecting cerebral blood flow pulsatility. This study depicts TCD findings of diabetes related cerebral hemodynamic changes and suggest that the PI reflects microangiopathic changes of cerebral vessels.