Uric acid elevations differ between equivalent hydrochlorothiazide and indapamide doses

Introduction: Thiazide diuretics are among the major anti-hypertensive medications. Hydrochlorothiazide and indapamide are among the most commonly used thiazides. Common side effects include impaired renal function and electrolyte disturbances. Whether hydrochlorothiazide and indapamide cause the same amount of disturbance at equivalent doses is uncertain. Methodology: Patient data from four different clinics was analyzed. Patients whose thiazide diuretic was initiated or dose escalated were included if they met the inclusion criteria. Patient characteristics, including demographics, comorbidities, medications, renal function, and electrolyte values at the initial visit and control visit, and hydrochlorothiazide or indapamide exposure per milligram, were acquired. Indapamide doses were multiplied by ten to convert into equivalent thiazide doses. Changes in renal function and electrolyte values, and renal function and electrolyte changes per equivalent thiazide exposure, were calculated. Results: The uric acid increase and potassium decrease were different for the indapamide and hydrochlorothiazide groups. However, when these changes were analyzed per equivalent thiazide exposure, potassium was not different, but the uric acid increase was still significantly different between indapamide and hydrochlorothiazide (.05(.08) vs .03 (.08) mg/dL per equivalent mg thiazide, p = .049). Discussion: This study demonstrated that indapamide’s hyperuricemic effect is more profound than that of hydrochlorothiazide. Choosing hydrochlorothiazide instead of indapamide may be more appropriate in patients with higher initial uric acid levels.