Effects of losartan/hydrochlorothiazide on serum uric acid levels and blood pressure in hypertensive patients.

The effect of a mixed formulation of 50 mg losartan (LOS) and 12.5 mg hydrochlorothiazide (HCTZ) on blood pressure and the uric acid metabolism was analyzed in 73 patients who switched to this formulation from other antihypertensive drugs. Eight patients who switched to the formulation from the regular dose of renin-angiotensin (RA) inhibitor (angiotensin receptor blocker [ARB] or angiotensin-converting enzyme [ACE] inhibitor) only showed a significant decrease in blood pressure, from 156.9 ± 14.1/88.6 ± 9.7 mmHg to 128.3 ± 16.0/76.1 ±10.7 mmHg (p = 0.007), and a significant increase in serum uric acid levels, from 5.2 ± 1.1 mg/dL to 6.8 ± 0.7 mg/dL (p = 0.02). In the other 50 patients who switched from a combination of the regular dose of RA inhibitor and calcium channel blocker (CCB), their blood pressure significantly increased, from 126.0 ± 13.8/72.0 ± 10.0 mmHg to 132.5 ± 16.4/76.5 ± 11.3 mmHg (p = 0.02), and their serum uric acid levels also significantly increased, from 5.6 ± 1.1 mg/dL to 6.1 ± 1.3 mg/dL (p = 0.0002). Considering that guidelines recommend using antihypertensive therapies that do not lead to an increase in serum uric acid levels, we conclude that using the ARB/HCTZ combination is less suitable than the regular dose of the ARB/CCB combination due to its effect on hypertension and serum uric acid levels.