Telmisartan/hydrochlorothiazide versus valsartan/hydrochlorothiazide in obese hypertensive patients with type 2 diabetes: the SMOOTH study.

Background: The Study of Micardis (telmisartan) in Overweight/Obese patients with Type 2 diabetes and Hypertension (SMOOTH) compared hydrochlorothiazide (HCTZ) plus telmisartan or valsartan fixed-dose combination therapies on early morning blood pressure (BP), using ambulatory BP monitoring (ABPM).

Methods: SMOOTH was a prospective, randomized, open-label, blinded-endpoint, multicentre trial. After a 2- to 4-week, single-blind, placebo run-in period, patients received once-daily telmisartan 80 mg or valsartan 160 mg for 4 weeks, with add-on HCTZ 12.5 mg for 6 weeks (T/HCTZ or V/HCTZ, respectively). At baseline and week 10, ambulatory blood pressure (ABP) was measured every 20 min and hourly means were calculated. The primary endpoint was change from baseline in mean ambulatory systolic and diastolic blood pressure (SBP; DBP) during the last 6 hours of the 24-hour dosing interval.

Results: In total, 840 patients were randomized. At week 10, T/HCTZ provided significantly greater reductions versus V/HCTZ in the last 6 hours mean ABP (differences in favour of T/HCTZ: SBP 3.9 mm Hg, p < 0.0001; DBP 2.0 mm Hg, p = 0.0007). T/HCTZ also produced significantly greater reductions than V/HCTZ in 24-hour mean ABP (differences in favour of T/HCTZ: SBP 3.0 mm Hg, p = 0.0002; DBP 1.6 mm Hg, p = 0.0006) and during the morning, daytime and night-time periods (p < 0.003). Both treatments were well tolerated.

Conclusion: In high-risk, overweight/obese patients with hypertension and type 2 diabetes, T/HCTZ provides significantly greater BP lowering versus V/HCTZ throughout the 24-hour dosing interval, particularly during the hazardous early morning hours.