BACKGROUND
Telmisartan, used for the treatment of hypertension, has been shown to function as a partial agonist of peroxime proliferative activated receptor-nu (PPAR-nu). Theoretically, telmisartan which simultaneously blocks the angiotensin II receptor and activates PPAR-nu should be more effective in improving atherosclerotic surrogate markers than angiotensin II receptor blockers alone. Therefore, this pilot study was designed to evaluate and compare the efficacy of telmisartan and valsartan on plasma adiponectin levels and pulse wave velocity as a marker of arterial stiffness in patients with type 2 diabetes. METHODS: Thirty two patients with type 2 diabetes (mean duration 7.6 +/- 5.1 years) taking oral hypoglycemic agents were randomly assigned to receive telmisartan or valsartan for 12 weeks. RESULTS: Telmisartan and valsartan treatment significantly increased circulating adiponectin levels (P = 0.013 and P = 0.013, respectively) and reduced systolic (P = 0.001 and P = 0.002, respectively) and diastolic blood pressure (P = 0.001 and P < 0.001, respectively), and brachial-ankle PWV (P = 0.019 and P = 0.002, respectively), without significant differences between the two treatments. Before and after treatment, the fasting plasma glucose, interleukin-6, homeostasis model of assessment insulin resistance (HOMAIR) levels and lipid profile were unchanged in both treatment groups. CONCLUSION: Contrary to our expectation, telmisartan, even with its partial PPAR-nu activity, is not superior to valsartan in improving plasma adipocytokine levels and arterial stiffness in patients with type 2 diabetes. These data suggest that the partial PPAR-nu activity of telmisartan beyond valsartan may have less significant therapeutic implications than expected in treating patients with type 2 diabetes.