Comparison of the effects of telmisartan and nifedipine gastrointestinal therapeutic system on blood pressure control, glucose metabolism, and the lipid profile in patients with type 2 diabetes mellitus and mild hypertension: a 12-month, randomized, double-blind study

Abstract

Background: Angiotensin receptor blockers (ARBs) provide effective blood pressure control. Whereas none of the ARBs appear to affect glucose homeostasis, some ARBs have been associated with a decrease in cholesterolemia.

Objective: This study was conducted to evaluate blood pressure control glucose homeostasis, and the plasma lipid profile in patients with type 2 diabetes mellitus and mild hypertension during 12 months of treatment with the ARB telmisartan or nifedipine gastrointestinal therapeutic system (GITS).

Methods: In this double-blind trial, patients taking oral hypoglycemic agents were randomized to receive telmisartan 40 mg or nifedipine GITS 20 mg once daily for 12 months. At the time of enrollment, patients were given advice on diet (1400-1600 kcal/d) and exercise (stationary bicycle for > or =30 min, 4 d/wk). Assessments of systolic blood pressure (SBP), diastolic blood pressure, body mass index (BMI), fasting plasma glucose concentrations, glycosylated hemoglobin, fasting plasma insulin concentrations, the homeostasis model assessment of insulin resistance, and the lipid profile were performed at baseline and after 6 and 12 months of treatment.

Results: One hundred sixteen patients were divided into 2 age- and sex-matched treatment groups (58 men, 58 women; mean [SD] age, 52.5 [5] years). All patients were in good general health at baseline; had achieved adequate glycemic control with diet and oral hypoglycemic agents; were taking antihypercholesterolemic drugs; and had no evidence of macroangiopathy, microalbuminuria, or neuropathy. There were significant reductions from baseline in seated trough SBP after 12 months of treatment with both telmisartan and nifedipine GITS (from 139 [4] to 132 [4] mm Hg and from 140 [4] to 130 [4] mm Hg, respectively; both, P < 0.01). No change in BMI or glucose metabolism was observed with either treatment. After 12 months, there were significant improvements in concentrations of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) with telmisartan (-9% and -11.5%, respectively; both, P < 0.01) compared with nifedipine GITS (-2% and -1.5%).

Conclusions: In this selected sample of patients with type 2 diabetes and mild hypertension, both telmisartan and nifedipine GITS produced significant reductions in blood pressure. Telmisartan was associated with a slight but statistically significant improvement in plasma TC and LDL-C concentrations compared with nifedipine GITS.