To compare the frequency of stone-related events among patients receiving thiazides, alkali citrate, and allopurinol without prior 24-hour urine testing. It is unknown whether one preventative pharmacological therapy (PPT) medication class is more beneficial for reducing kidney stone recurrence when prescribed empirically.
Using medical claims data from working-age adults with kidney stone disease diagnoses (2008-2018), we identified those prescribed thiazides, alkali citrate, or allopurinol. We excluded those who received 24-hour urine testing prior to initiating PPT and those with less than three years of follow-up. We fit multivariable regression models to estimate the association between the occurrence of a stone-related event (emergency department visit, hospitalization, or surgery for stones) and PPT medication class.
Our cohort consisted of 1,834 (60%), 654 (21%), and 558 (18%) patients empirically prescribed thiazides, alkali citrate, or allopurinol, respectively. After controlling for patient factors including medication adherence and concomitant conditions that increase recurrence risk, the adjusted rate of any stone event was lowest for the thiazide group (14.8%) compared to alkali citrate (20.4%) or allopurinol (20.4%) (each p<0.001). Thiazides, compared to allopurinol, were associated with 32% lower odds of a subsequent stone event by three years (OR 0.68, 95% CI 0.53-0.88). No such association was observed when comparing alkali citrate to allopurinol (OR 1.00, 95% CI 0.75-1.34).
Empiric PPT with thiazides is associated with significantly lower odds of subsequent stone-related events. When 24-hour urine testing is unavailable, thiazides may be preferred over alkali citrate or allopurinol for empiric PPT.
Urology. 2022 May 08 [Epub ahead of print]
Ryan S Hsi, Phyllis L Yan, Joseph J Crivelli, David S Goldfarb, Vahakn Shahinian, John M Hollingsworth
Department of Urology, Vanderbilt University Medical Center. Electronic address: ., Dow Division of Health Services Research, Department of Urology, University of Michigan. Electronic address: ., Department of Urology, University of Alabama at Birmingham School of Medicine. Electronic address: ., Nephrology Section, VA New York Harbor Healthcare System, Division of Nephrology, New York University Langone Medical Center. Electronic address: ., Dow Division of Health Services Research, Department of Urology, University of Michigan, Division of Nephrology, Department of Internal Medicine, University of Michigan. Electronic address: ., Dow Division of Health Services Research, Department of Urology, University of Michigan. Electronic address: .