ABSTRACT
BACKGROUND AND OBJECTIVES: Telmisartan has been reported to have beneficial effects on insulin resistance and lipid profiles by acting as a peroxisome proliferator-activated receptor-γ (PPARγ) agonist. In this study we investigated the relationship between telmisartan dose and glycaemic control in Japanese subjects with type 2 diabetes mellitus and hypertension. METHODS: Patients (n = 263) who were prescribed telmisartan 20, 40 or 80 mg/day at our clinic were retrospectively identified from our clinical database. Only patients without changes in their treatments for diabetes and hypertension for 6 months after starting telmisartan were included in this study. Glycosylated haemoglobin A(1c) (HbA(1c)) levels were measured at 0, 3 and 6 months after starting telmisartan. RESULTS: At 3 and 6 months after starting telmisartan, HbA(1c) levels were significantly decreased in patients treated with telmisartan 40 or 80 mg/day but not in patients treated with telmisartan 20 mg/day (mean ± standard error change at 6 months: -0.29 ± 0.10%, p < 0.001; -0.48 ± 0.15%, p < 0.001; and -0.03 ± 0.10%, p = 0.33; respectively). When patients were classified into two groups by telmisartan dose (20 vs ≥40 mg/day), there was no significant correlation between baseline HbA(1c) and change in HbA(1c) levels over time in the 20 mg/day group. However, in patients treated with ≥40 mg/day of telmisartan, baseline HbA(1c) was negatively correlated with the change in HbA(1c) at 6 months. Multiple regression analysis confirmed that baseline HbA(1c) and telmisartan dose were the predictive factors. CONCLUSION: Our results suggest that telmisartan influences glycaemic control in a dose-dependent manner; doses ≥40 mg/day may be needed to improve glycaemic control. Our data also suggest that patients with higher baseline HbA(1c) may experience greater improvements in glycaemic control with telmisartan.
