Higher Thiazide Doses May Help Prevent Kidney Stones: JAMA finds

The JAMA Network Open Study has highlighted that increasing thiazide dosage was associated with greater reductions in calcium, hence it could prevent kidney stones recurrence in patients.

For the study, researchers used the Medicare-Litholink Database to find adults with kidney stones who were prescribed thiazide medications (like hydrochlorothiazide, chlorthalidone, or indapamide) within 6 months of their first 24-hour urine test. They also looked at patients who had follow-up urine tests done between 30 and 180 days after starting their thiazide prescription.

Thiazide dosages were categorized as, low(Chlorthalidone < 12.5 mg/day; Indapamide < 0.6125 mg/day; Hydrochlorothiazide < 25 mg/day), medium(Chlorthalidone 12.5 to < 25 mg/day; Indapamide 0.6125 to < 1.25 mg/day; Hydrochlorothiazide 25 to < 50 mg/day) and high(Chlorthalidone ≥ 25 mg/day; Indapamide ≥ 1.25 mg/day; Hydrochlorothiazide ≥ 50 mg/day).

Researchers assessed how calcium levels changed with low, medium, and high thiazide dosages and linked these changes to the occurrence of symptomatic kidney stone events, such as emergency visits, hospitalizations, or surgeries, within 6 to 48 months after starting the prescription.

Results revealed that higher thiazide doses were associated with greater reductions in urine calcium levels, with a low dose resulting in an 18.9% reduction, a medium dose in a 25.5% reduction, and a high dose in a 28.4% reduction.

Reference: Hsi RS, Yan PL, Maalouf NM, et al. Thiazide Dose, Urine Calcium, and Symptomatic Kidney Stone Events. JAMA Netw Open. 2024;7(8):e2428953. doi:10.1001/jamanetworkopen.2024.28953