title: Effectiveness of hydrochlorothiazide in combination with telmisartan and olmesartan in adults with moderate hypertension not controlled with monotherapy: a prospective, randomized, open-label, blinded end point (PROBE), parallel-arm study.
abstract: BACKGROUND
  The potential combinations of antihypertensive agents are many, and making rational choices depends on the characteristics of each drug and on their complementary mechanisms of action.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the effectiveness of adding hydrochlorothiazide (HCTZ) 12.5 mg to olmesartan 20 mg or telmisartan 80 mg on blood pressure (BP) in patients with moderate hypertension.
  
  
  METHODS
  Consecutive outpatients at the Centro per l'Ipertensione e la Fisiopatologia Cardiovascolare, University of Pavia, Pavia, Italy, of both sexes aged 39 to 75 years were considered eligible for enrollment if they had a sitting diastolic BP (DBP) ->99 mm Hg and <110 mm Hg at the end of an initial 2-week washout period. Patients were random- ized to olmesartan 20 mg QD or telmisartan 80 mg QD according to a prospective, open-label, blinded end point, parallel-arm design. After 8 weeks of monotherapy, patients whose BP was not controlled (DBP ->90 mm Hg) received HCTZ 12.5 mg QD for 8 additional weeks. Clinical and ambulatory BPs were measured at the end of the washout period and at the end of both treatment periods. Adverse events (AEs) were recorded from spontaneous reports and direct inquiry from investigators.
  
  
  RESULTS
  One hundred forty-five patients, all of whom were white, were recruited for the study. After the initial washout period, 13 patients did not meet the inclusion criteria and 6 refused to continue. A total of 126 white patients (69 men, 57 women; mean [SD] age, 60.2 [11.6] years) were randomized to receive monotherapy. Of these, 35 patients (56%) in the olmesartan group and 33 (52%) in the telmisartan group had previously received antihypertensive therapy. At the end of monotherapy, the 52 patients in the olmesartan group and the 49 patients in the telmisartan treatment group who were still in the study and had their BP inadequately controlled by treatment had HCTZ 12.5 mg QD added to their treatment regimen. Both combinations induced a greater ambulatory mean (SD) systolic BP (SBP) and DBP reduction than monothera- py (SBP: 145.3 [6.1] in the olmesartan group and 140.1 [6.4] in the telmisartan group, P < 0.05; DBP: 88.1 [5.1] in the olmesartan group and 84.9 [4.9] in the telmisartan group, P < 0.05). The mean (SD) reduction from baseline in the telmisartan/HCTZ-treated patients (21.5 [10.1]/14.6 [5.2] mm Hg for 24 hours, 21.8 [10.2]/14.9 [5.2] mm Hg for daytime, and 20.4 [10.3]/13.7 [5.9] mm Hg for nighttime; all, P < 0.001 vs baseline) was significantly greater than that observed in the olmesartan/HCTZ-treated patients (18.8 [9.8]/12.3 [4.9] mm Hg for 24 hours, 19.3 [9.8]/12.8 [4.9] mm Hg for daytime, and 17.4 [10.2]/10.6 [5.5] mm Hg for nighttime; all, P < 0.001 vs baseline), with a significant difference between the 2 treatment groups (P < 0.01). Compared with mono- therapy, the add-on effect of HCTZ 12.5 mg QD administration was significantly greater in the telmisartan group than in the olmesartan group (P < 0.05); the differ- ence being more evident for nighttime BP values (SBP, P 0.031; DBP, P 0.025). Reported AEs were similar in the olmesartan/HCTZ and the telmisartan/HCTZ groups (4 patients [7%] vs 3 patients [6%]).
  
  
  CONCLUSIONS
  The addition of HCTZ 12.5 mg to telmisartan 80 mg monothera- py was associated with greater BP reduction than the addition of the same dose of HCTZ to olmesartan 20 nag monotherapy in these patients previously uncontrolled on monotherapy.
authors.affiliation: Department of Internal Medicine and Therapeutics, Centro per l'Ipertensione e la Fisiopatologia Cardiovascolare, University of Pavia, Pavia, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Fogari
authors.affiliation: Department of Internal Medicine and Therapeutics, Centro per l'Ipertensione e la Fisiopatologia Cardiovascolare, University of Pavia, Pavia, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Zoppi
authors.affiliation: Department of Internal Medicine and Therapeutics, Centro per l'Ipertensione e la Fisiopatologia Cardiovascolare, University of Pavia, Pavia, Italy.
authors.forename: Amedeo
authors.initials: A
authors.lastname: Mugellini
authors.affiliation: Department of Internal Medicine and Therapeutics, Centro per l'Ipertensione e la Fisiopatologia Cardiovascolare, University of Pavia, Pavia, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Preti
authors.affiliation: Department of Internal Medicine and Therapeutics, Centro per l'Ipertensione e la Fisiopatologia Cardiovascolare, University of Pavia, Pavia, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Destro
authors.affiliation: Department of Internal Medicine and Therapeutics, Centro per l'Ipertensione e la Fisiopatologia Cardiovascolare, University of Pavia, Pavia, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Rinaldi
authors.affiliation: Department of Internal Medicine and Therapeutics, Centro per l'Ipertensione e la Fisiopatologia Cardiovascolare, University of Pavia, Pavia, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Derosa
keywords: hydrochlorothiazide; hypertension; olmesartan; telmisartan