To compare the frequency of stone-related events among subgroups of high-risk patients with and without 24-hour urine testing before PPT prescription. While recent studies show, on average, no benefit to a selective approach to preventive pharmacological therapy (PPT) for urinary stone disease (USD), there could be heterogeneity in treatment effect across patient subgroups.
Using medical claims data from working-age adults and their dependents with USD (2008-2019), we identified those with a prescription fill for a PPT agent (thiazide diuretic, alkali therapy, or allopurinol). We then stratified patients into subgroups based on the presence of a concomitant condition or other factors that raised their stone recurrence risk. Finally, we fit multivariable regression models to measure the association between stone-related events (emergency department visit, hospitalization, and surgery) and 24-hour urine testing before PPT prescription by high-risk subgroup.
Overall, 8,369 adults with USD had a concomitant condition that raised their recurrence risk. Thirty-three percent (n=2,722) of these patients were prescribed PPT after 24-hour urine testing (median follow-up, 590 days), and 67% (n=5,647) received PPT empirically (median follow-up, 533 days). Compared to patients treated empirically, those with a history of recurrent USD had a significantly lower hazard of a subsequent stone-related event if they received selective PPT (hazard ratio, 0.83; 95% CI, 0.71-0.96). No significant associations were noted for selective PPT in the other high-risk subgroups.
Patients with a history of recurrent USD benefit from PPT when guided by findings from 24-hour urine testing.
Urology. 2022 Feb 16 [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. Electronic address: ., Dow Division of Health Services Research, Department of Urology, University of Michigan. Electronic address: .