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 reninangiotensin 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 Thereafter, telmisartan and losartan were withdrawn in both groups.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. Turk Jem 2013; 17: 92-97 Key words: Telmisartan, losartan, insulin resistance Amaç: Anjiotensin Reseptör Blokörleri (ARB) insülin direncini düzeltmektedir. ARB grubundan telmisartanın Renin-anjiotensin-sistemi inhibisyonundan bağımsız, parsiyel PPAR-gamma aktivitesi göstererek insülin duyarlılığını arttırdığı gösterilmiştir. Bir başka ARB olan losartanda bu aktivite bulunamamıştır. Çalışmamızda tip 2 diyabetik hastalarda telmisartan ve losartanın insülin direnci üzerine etkilerini karşılaştırmayı amaçladık. Gereç ve Yöntem: Çalışmaya üç aydır telmisartan yada losartan alan, sulfonilüre tedavisi ile metabolik kontrolü sağlanmış 2 diyabetli hastalar alındı. Hastaların antropometrik ölçümleri alındı, açlık plazma glukozu, HbA1C, bazal insülin ve serum adiponektin düzeyleri belirlendi; HOMA-IR hesaplandı. Hiperinsülinemik-öglisemik klemp testiyle insülin duyarlılığını yansıtan M değerleri bulundu. Takiben hastaların almış olduğu ARB kesildi. On beş günlük ilaçtan temizlenme periyodunu takiben önceden losartan almış olan gruba (Grup 1) telmisartan (80 mg/gün), önceden telmisartan almış gruba (Grup 2) losartan (50 mg/gün) verildi. On iki hafta takip sonunda hastalara bahsedilen antropometrik ölçümler ve laboratuvar testleri ile hiperinsülinemik öglisemik klemp testi tekrarlandı. Bulgular: Çalışmayı 1. Gruptan dokuz, 2. Gruptan sekiz hasta tamamladı. Başl...