Data supporting the efficacy of preventive pharmacological therapy (PPT) to reduce urolithiasis recurrence are based on clinical trials with composite outcomes that incorporate imaging findings and which have uncertain clinical significance. This study sought to evaluate if the use of PPT leads to fewer symptomatic stone events.
Retrospective cohort study.
& Participants: Medicare enrollees with urolithiasis who completed 24-hour urine collections that revealed hypercalciuria, hypocitraturia, low urine pH, or hyperuricosuria.
PPT (thiazide diuretics for hypercalciuria, alkali for hypocitraturia or low urine pH, or uric acid lowering drugs for hyperuricosuria) categorized as, 1) adherent to guideline-concordant PPT, 2) nonadherent to guideline-concordant PPT, or 3) untreated.
Symptomatic stone event occurrence (emergency department [ED] visit or hospitalization for urolithiasis or stone-directed surgery).
Cox proportional hazards regression.
Among 13,942 patients, 31.0% were prescribed PPT. Compared to no treatment, concordant/adherent PPT use was associated with a significantly lower hazard of symptomatic stone events for patients with hypercalciuria (hazard ratio [HR], 0.736 [95% confidence interval (CI), 0.593 to 0.915]) and low urine pH (HR, 0.804 [CI, 0.650 to 0.996]) but not for patients with hypocitraturia or hyperuricosuria. These associations were largely driven by significantly lower rates of ED visits after initiating PPT among the concordant/adherent group versus untreated patients. Patients with hypercalciuria had adjusted two-year predicted probabilities of a visit of 3.8% [95% CI, 2.5% to 5.2%%] and 6.9% [95% CI, 6.0% to 7.7%] for the concordant/adherent PPT and no-treatment groups, respectively. Among patients with low urine pH, these probabilities were 4.3% [95% CI, 2.9% to 5.7%] and 7.3% [95% CI, 6.5% to 8.0%] for the concordant/adherent PPT and no-treatment groups, respectively.
Potential bias from the possibility that patients prescribed PPT had more severe disease than untreated patients.
Patients with urolithiasis and hypercalciuria who were adherent to treatment with thiazide diuretics as well as those with low urine pH adherent to prescribed alkali therapy had fewer symptomatic stone events than untreated patients.
American journal of kidney diseases : the official journal of the National Kidney Foundation. 2024 Feb 18 [Epub ahead of print]
John M Hollingsworth, Mary K Oerline, Ryan S Hsi, Joseph J Crivelli, Noah Krampe, John R Asplin, Vahakn B Shahinian
NorthShore University HealthSystem, Evanston, IL, USA; Dow Division of Health Services Research, Department of Urology, University of Michigan Medical School, Ann Arbor, MI, USA. Electronic address: ., Dow Division of Health Services Research, Department of Urology, University of Michigan Medical School, Ann Arbor, MI, USA., Department of Urology, Vanderbilt University Medical Center, Nashville, TN, USA., Department of Urology, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA., Litholink, Laboratory Corporation of America Holdings, Itasca, IL, USA., Dow Division of Health Services Research, Department of Urology, University of Michigan Medical School, Ann Arbor, MI, USA; Division of Nephrology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA.