FLOW MEDIATED-DILATATION IS ALREADY ABNORMAL IN PRE-IMPAIRED GLUCOSE TOLERANCE (PRE-IGT) AND WITH NO CORRELATION WITH SYSTOLIC BLOOD PRESSURE AND DIASTOLIC BLOOD PRESSURE

Abstract

Objective: Pre-impaired glucose tolerance (Pre-IGT) is a stage of compensatory hyperinsulinemia to maintain normoglycemia. It is the earliest stage of glucose dysmetabolism, where beta cells can still compensate for the insulin resistance thru hyperinsulinemia. Endothelial dysfunction is a critical part in the pathogenesis of macrovascular and microvascular chronic complications in type 2 diabetes, ordinarily due to uncontrolled hyperglycemia. In pre-IGT the main problem is hyperinsulinemia on a background of normal blood sugar. C-peptide, a segment cleaved off from pro-insulin is equimolar to insulin, and has shown to cause intima media thickening. This study was undertaken to determine endothelial function of patients with pre-IGT thru flow-mediated dilatation of the brachial artery and to correlate the FMD with the insulin level, systolic blood pressure and diastolic blood pressure. Design and method: This is a cross-sectional analytical study of adult patients with risk factors for developing diabetes such as, having first-degree relative with diabetes, obesity, history of gestational diabetes, and polycystic ovary syndrome (PCOS). Systolic and diastolic BP, BMI, 2-hour serum insulin, blood sugar, and lipids were determined. Patients with pre-IGT underwent brachial artery FMD. Results: Of the 27 subjects, 21 (77.8%) had pre-IGT. The mean oral glucose tolerance test at 2-hours post-prandial was normal at 109.53 mg/dL (SD = 30.26). Results of the laboratory tests were as follows: mean Hba1c and insulin at 2 hours were 5.34% (SD = 0.44) and 112.21 uIU/mL (SD = 111.24, normal range 2.60–24.90), respectively. Comparative analyses of the demographic and clinical profiles showed similar characteristics between the normoinsulinemic and the pre-IGT subjects (p > 0.05), although there were more with positive history of type 2 DM and obesity on the latter group. Systolic and diastolic BP levels were normal. Of the 27 subjects, four (4) had abnormal FMD which had a small positive correlation with thee insulin level, systolic BP, and diastolic BP, although not statistically significant (p > 0.05). Conclusions: Endothelial dysfunction has shown to exist already in the pre-IGT subjects depicted in the abnormality in the arterial flow-mediated dilatation study. Systolic BP and diastolic BP levels have not shown any significant correlation with the FMD finding, and the insulin level.