The Effects of Telmisartan and Losartan on Insulin Sensitivity

ABSTRACT

Purpose: Telmisartan has been reported to increase insulin sensitivity by acting as a partial PPAR-gamma agonist, regardless of its renin-angiotensin system inhibition, but losartan has no such activity. In this study, we compared the effects of telmisartan and losartan on insulin sensitivity among type 2 diabetic patients.
Material and Method: Age-, sex- and weight-matched patients, who had been on telmisartan or losartan treatment for at least 3 months, were included. Their anthropometric measurements were performed, blood pressures were recorded. Fasting venous blood samples were obtained for analyzing the levels of glucose, HbA1C, insulin and adiponectin. HOMA-IR was calculated. An euglycemic hyperinsulinemic clamp procedure was performed in each subject and M index was calculated. Thereafter, telmisartan and losartan were withdrawn in both groups. A cross-over design was planned; following a wash-out period of 15 days, losartan group (Group 1) was given telmisartan 80 mg/day, telmisartan group (Group 2) was administered losartan 50 mg/day. After 12 weeks of therapy, all measurements, calculations and the euglycemic hyperinsulinemic clamp test were re-performed.
Results: General characteristics of the patients at inclusion were similar. Nine cases in group 1 and 8 cases in Group 2 concluded the follow-up. In Group 1, among all follow-up parameters, only weight exhibited a significant decrease at final evaluation (p=0,034). In Group 2, only M value was found to increase (p=0,028).
Discussion: Our findings indicated that losartan improved insulin sensitivity in patients with concomitant hypertension and type 2 diabetes, and telmisartan use resulted in more weight loss.