The effects of the addition of losartan on uric acid metabolism in patients receiving indapamide.

Abstract

A number of adverse metabolic effects are associated with indapamide administration, including an increase in serum uric acid levels. It has been reported that losartan can significantly decrease serum uric acid levels. However, there are no data on the effects of combination therapy of losartan with indapamide on uric acid metabolism. We studied 20 hypertensive patients in whom serum metabolic parameters, including uric acid levels in serum and urine, were studied before and after eight weeks of indapamide administration (2.5 mg once daily) as well as eight weeks after combination treatment with indapamide (2.5 mg once daily)and losartan (50 mg/day). Indapamide evoked a significant decrease in systolic and diastolic blood pressure from a mean value of 157 +/- 12 mmHg/96 +/- 10 mmHg to a mean value of 139 +/- 14 mmHg/92 +/- 5 mmHg (p<0.01 for both comparisons). However, a significant increase in serum uric acid levels was noticed after indapamide administration (from a mean value of 4.9 +/- 1.6 mg/dl to a mean value of 5.9 +/- 1.2 mg/dl, p<0.01), associated with a decrease in the fractional excretion of uric acid(from a mean value of 9 +/- 5% to a mean value of 7 +/- 5.5%, p<0.05). The addition of losartan caused a further decrease in blood pressure from a mean value of 139 +/- 14 mmHg/92 +/- 5 mmHg to a mean value of 120 +/- 15 mmHg/84 +/- 4 mmHg (p<0.01 for both comparisons). This was followed by a significant decrease in serum uric acid levels to 5 +/- 1.1 mg/dl(p<0.01) due to a substantial increase in fractional urate excretion (from 7 +/- 5.5 to 8.7 +/- 6%, p<0.05). The addition of losartan could offset the hyperuricaemic effect of indapamide administration.