Effect of Telmisartan Versus Captopril on Insulin Resistance in Hypertensive Type 2 Diabetic Patients

Abstract

Background and objectives: Hypertension is an extremely common co-morbid condition in diabetes.Peripheral insulin resistance (IR) plus compensatory hyperinsulinaemia is a common mechanismunderlying both hypertension and diabetes. The aim of this study was to compare the effects oftelmisartan and captopril on IR in type2 diabetes mellitus with hypertension.Materials and Methods: This study was conducted in the Department of Pharmacology, Mosul Collegeof Medicine, University of Mosul and Al-Wafaa center for diabetes management, Mosul, Iraq, from 1March, 2012 to 30 March, 2013. Sixty-eight patients on oral hypoglycemic agents were assigned toreceive two month treatment of either telmisartan (n = 34) or captopril (n = 34). Forty diabeticnormotensive patients, with age and BMI, matched to the diabetic hypertensive patients, served as acontrol group. The oral hypoglycemic agents remained unchanged during the two- months study period.Insulin resistance was estimated by homeostasis model assessment of insulin resistance (HOMA-IR) andquantitative insulin sensitivity check index (QUICKI).Results: This study showed that the two groups of diabetic hypertensive patients who were assigned toreceive captopril or telmisartan have a non-significant difference in fasting serum glucose (FSG), fastingserum insulin (FSI), QUICKI and HOMA- IR before starting therapy. Telmisartan and captopril groupsshowed insignificant change in body mass index (BMI). HOMA-IR, QUICKI, FSI and FSG werechanged non-significantly in telmisartan group; while FSI, FSG and HOMA-IR decreased significantly(from 18.1± 9.69 to 15.14 ± 7.49, p=0.022; and from 187.32± 65.34 to 162.95 ± 56.87, p=0.048; and from8.27 ± 6.28 to 6.02 ± 3.73, p-value= 0.027, respectively) and QUICKI increased significantly (from 0.293± 0.024 to 0.306 ± 0.031, p-value = 0.022) in the captopril group versus baseline.Conclusion: Captopril, but not telmisartan, significantly improves insulin sensitivity in diabetichypertensive patients.Keywords: Captopril, HOMA-IR, telmisartan, type 2 diabetes.