Mp26-17 Risk of Nephrolithiasis in Long-Term Topiramate and Zonisamide Users

You have accessJournal of UrologyStone Disease: Medical & Dietary Therapy (MP26)1 May 2024MP26-17 RISK OF NEPHROLITHIASIS IN LONG-TERM TOPIRAMATE AND ZONISAMIDE USERS Bassel S. Salka, Mary K. Oerline, Phyllis Yan, Ryan S. Hsi, Joseph J. Crivelli, John R. Asplin, Vahakn B. Shahinian, and John M. Hollingsworth Bassel S. SalkaBassel S. Salka , Mary K. OerlineMary K. Oerline , Phyllis YanPhyllis Yan , Ryan S. HsiRyan S. Hsi , Joseph J. CrivelliJoseph J. Crivelli , John R. AsplinJohn R. Asplin , Vahakn B. ShahinianVahakn B. Shahinian , and John M. HollingsworthJohn M. Hollingsworth View All Author Informationhttps://doi.org/10.1097/01.JU.0001009408.66023.77.17AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: As treatment indications for topiramate and zonisamide (TZ) have expanded, so too has their use, which is potentially concerning from a kidney stone perspective, given these medications' effects on urine chemistries. In this context, we conducted a retrospective cohort study to examine the relationship between TZ use and kidney stone risk. METHODS: Between 2011 and 2019, we identified a group of working-age (Optum) and older adults (Medicare) who were TZ users (i.e., they had at least one prescription fill for either medication), as well as a group of age- and sex-matched nonusers. Next, we measured the frequency of symptomatic stone events (defined as an emergency department visit, hospitalization, or surgery for kidney stones) in these two groups. We then fit multivariable Cox models to estimate the hazard of a symptomatic stone event as a function of TZ use. RESULTS: A total of 1,122,301 adults were included in our study. Compared to nonusers, TZ users were more likely to be white, reside in the southern U.S., and have higher levels of comorbid illness (p<0.001 for each comparison). They were also more like to have a diagnosis that predisposed them to kidney stone formation like gout and gastrointestinal disease (p<0.001). The Figure 1 illustrates the unadjusted cumulative incidence of a symptomatic kidney stone event among TZ users (blue line) and nonusers (pink). Between 3 months and 3 years of follow-up, the incidence was 2.9% and 2.0% for TZ users versus 1.2% and 1.3% for nonusers in the Optum (panel A) and Medicare (panel B) cohorts, respectively (p<0.001 for each comparison). After controlling for measured patient differences, TZ users had a significantly higher hazard than nonusers of experiencing a symptomatic stone event (Optum: HR, 1.58 [95% CI, 1.49-1.68]; Medicare: HR, 1.22 [95% CI, 1.11-1.34]). A dose-response relationship was observed such that the hazard of a symptomatic stone event increased with higher medication dosages. CONCLUSIONS: Patients on TZ have a higher risk of symptomatic kidney stones than their age- and sex- matched controls. Therefore, clinicians who prescribe TZ should be fully transparent about this risk when they counsel patients. Download PPT Source of Funding: The National Institute of Diabetes and Digestive and Kidney Diseases © 2024 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 211Issue 5SMay 2024Page: e420 Advertisement Copyright & Permissions© 2024 by American Urological Association Education and Research, Inc.Metrics Author Information Bassel S. Salka More articles by this author Mary K. Oerline More articles by this author Phyllis Yan More articles by this author Ryan S. Hsi More articles by this author Joseph J. Crivelli More articles by this author John R. Asplin More articles by this author Vahakn B. Shahinian More articles by this author John M. Hollingsworth More articles by this author Expand All Advertisement PDF downloadLoading ...