Long-term efficacy of combination therapy with losartan and low-dose hydrochlorothiazide in patients with uncontrolled hypertension

We evaluated the long-term efficacy of losartan and low-dose hydrochlorothiazide combination therapy in the treatment of hypertension. We enrolled 15 Japanese hypertensive outpatients whose 24-hour ambulatory blood pressure was >or= 135/80 mmHg after candesartan 8 mg (CND group; n = 10) monotherapy or amlodipine 5 mg (AML group; n = 5) monotherapy for 2 months or more. The monotherapy was then switched to losartan 50 mg and hydrochlorothiazide 12.5 mg combination therapy. Ambulatory blood pressure and indices of glucose and lipid metabolism were measured at the end of the monotherapy and after 3 and 12 months of the combination therapy. In the CND group, 24-hour blood pressure decreased significantly from 137 +/- 9/89 +/- 4 to 126 +/- 8/81 +/- 7 mmHg after 3 months (P < 0.05/ P < 0.001) and to 123 +/- 7/81 +/- 4 mmHg after 12 months (P < 0.01/P < 0.001). In the AML group, 24-hour blood pressure decreased significantly from 137 +/- 11/81 +/- 7 to 125 +/- 12/75 +/- 6 mmHg after 3 months (P < 0.05/P < 0.05) and to 124 +/- 9/77 +/- 7 mmHg after 12 months (P < 0.05/NS). There were significant decreases in systolic blood pressure during the daytime (6:00-21:30), nighttime (22:00-5:30) and early morning (6:00-8:00) after 12 months in both groups. No adverse changes in the indices of glucose or lipid metabolism were observed in either group. In conclusion, long-term combination therapy with losartan and low-dose hydrochlorothiazide was effective in the treatment of hypertensive patients whose blood pressure was not controlled by candesartan or amlodipine monotherapy alone.