Comparison of therapies between fixed-dose telmisartan/hydrochlorothiazide and losartan/hydrochlorothiazide in patients with mild to moderate hypertension

Abstract

Among angiotensin receptor blockers (ARBs), telmisartan is suggested to function as a partial agonist of peroxisome proliferator-activated receptor-γ (PPAR γ) and to improve lipid and glucose metabolism. Clinical benefits of telmisartan over other ARBs may be apparent in combination with diuretics. which have harmful influences on lipid and glucose metabolism. In the present study, 21 patients treated with mild to moderate hypertension (13 women and 8 men aged 63.1 ± 11.6 years) underwent a 24-week treatment period with telmisartan 40 mg and HCTZ 12.5 mg once daily, or a 24-week treatment period with losartan 50 mg and HCTZ 12.5 mg once daily, without a wash-out period, in a quasi-randomized cross-over manner. Their ambulatory blood pressure and metabolic parameters were measured after the 2 treatment periods. Ambulatory systolic and diastolic blood pressures did not differ signilicantly between the 2 treatment periods during 24 hours, daytime, night-time, and early-morning hours (06:00-08:00). Serum uric acid was insignificantly higher in the treatment period with telmisartan/HCTZ than in the treatment period with losartan/HCTZ (P = 0.086). Although serum total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol did not differ significantly, serum triglycerides were slightly higher in the treatment period with telmisartan/HCTZ than in the treatment period with losartan/HCTZ (P = 0.060). Parameters of glucose metabolism did not differ significantly between the 2 treatment periods. In conclusion. antihypertensive efficacy was similar between the 2 regimens throughout 24 hours, despite different elimination half-lives of telmisartan and losartan. Although telmisartan is suggested to function as a partial agonist of PPAR, no clinical benefit was found in combination with HCTZ with respect to lipid and glucose metabolism.