MP41-08 RANDOMIZED CONTROLLED TRIAL OF TWO VITAMIN D REPLETION PROTOCOLS TO ASSESS IMPACT ON CALCIUM EXCRETION IN STONE FORMERS

Abstract

You have accessJournal of UrologyStone Disease: Medical Therapy1 Apr 2015MP41-08 RANDOMIZED CONTROLLED TRIAL OF TWO VITAMIN D REPLETION PROTOCOLS TO ASSESS IMPACT ON CALCIUM EXCRETION IN STONE FORMERS Matthew Ferroni, Kevin Rycyna, Timothy Averch, and Michelle Semins Matthew FerroniMatthew Ferroni More articles by this author , Kevin RycynaKevin Rycyna More articles by this author , Timothy AverchTimothy Averch More articles by this author , and Michelle SeminsMichelle Semins More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1636AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES It is estimated that up to 90% of Americans have insufficient vitamin D levels which may have significant impact on a variety of chronic illnesses including cardiovascular disease and bone health. Over-repletion of vitamin D, however, may be a potential risk factor for nephrolithiasis, particularly in known stone formers, as it may be associated with hypercalciuria. A variety of accepted standard vitamin D repletion protocols exist, however their differing impact on urinary stone formation risk factors is unclear. METHODS Patients with a previous history of stone formation and who were found to have vitamin D insufficiency (<30ng/ml) on initial metabolic workup were randomized to receive vitamin D repletion with either 1,000 IU daily or 50,000 IU per week for a total of 6 weeks. All patients completed a pre-repletion 24-hour urine collection to assess their baseline stone formation risk parameters as well as post-repletion 24-urine collection to evaluate any changes. Patients also had serum vitamin D levels drawn before and after repletion. Statistical analysis was performed using Wilcoxon rank-sum tests and all data reported are median values with 95% confidence intervals. RESULTS 20 patients completed the study; 8 who received 1,000 IU daily and 12 who received 50,000 IU weekly. Patients receiving 50,000 IU showed significant improvement in serum vitamin D levels with a delta of 23ng/ml (144% increase, p<0.01) over pre-repletion level, while patients receiving 1,000 IU daily showed a non-significant delta of 8ng/ml (45% increase, p=0.14). The difference between the groups was also significant, p=0.04. Post-repletion 24-hour urine analysis showed no significant change in urine calcium among both groups; median change of -45.5mg in patients receiving 1,000 IU (-188, 29, p=0.34) and -10.3mg in those receiving 50,000 IU (-53.5, 81.7, p=0.82), or between them, p=0.44. Between the groups there was also no significant difference in either the super-saturation of calcium oxalate (changes of -1.28 and 0.8, p=0.23) or the calcium phosphate (changes of -0.65 and 0.5, p=0.28). CONCLUSIONS Neither dose of vitamin D supplementation increased urine calcium or the super-saturation of calcium salts in known stone formers. Based on the superior improvement in serum vitamin D levels in patients receiving 50,000 IU weekly, this regimen may be an effective treatment choice in stone formers who present with vitamin D insufficiency. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e502-e503 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Matthew Ferroni More articles by this author Kevin Rycyna More articles by this author Timothy Averch More articles by this author Michelle Semins More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...