MP25-17 THE EFFECT OF INCREASED VISCERAL FAT AREA AND BODY-MASS INDEX ON 24 HOUR URINE COLLECTION

Abstract

You have accessJournal of UrologyStone Disease: Basic Research II1 Apr 2014MP25-17 THE EFFECT OF INCREASED VISCERAL FAT AREA AND BODY-MASS INDEX ON 24 HOUR URINE COLLECTION Ethan Fram, Saman Moazami, Mira Herman, Ilir Agalliu, and Joshua Stern Ethan FramEthan Fram More articles by this author , Saman MoazamiSaman Moazami More articles by this author , Mira HermanMira Herman More articles by this author , Ilir AgalliuIlir Agalliu More articles by this author , and Joshua SternJoshua Stern More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.319AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The prevalence of obesity in the United States is increasing and with it the incidence of urinary stone disease. Obesity effects the composition of many urinary solutes. Visceral fat has been independently associated with many metabolic disturbances previously linked solely to obesity. We sought to evaluate the impact that visceral fat may have on urinary solutes, urinary volume, and serum uric acid in a cohort of patients with urolithiasis who were treated using ureteroscopy and laser lithotripsy (URS). METHODS We performed a retrospective review of an IRB-approved database of patients who had undergone URS at our institution in the last seven years. 24 hour urine collection results, stone characteristics, and patient demographics were recorded. VFA was calculated using pre-operative CT scanning using a slice taken at the level of the umbilicus (TeraRecon, Aquarius iNtuition workstation). Multivariate regression models were used to predict outcomes. RESULTS We identified 237 patients who met our criteria. The patients represented an ethnically diverse population with high prevalence of comorbidities. Upon multivariate analysis increasing BMI was found to predict high total quantity and concentration of a number of solutes, while VFA was associated with increasing 24-hour urine total quantities of sodium and creatinine (Table 1). Another multivariate analysis demonstrated that visceral fat area predicts uric acid stone formation (OR 1.007, p = .021). Neither visceral fat area nor BMI predicted other stone types. Finally, white ethnicity was associated with approximately 2.5 times as many uric acid stones than expected (X2 = 28.115, p = .031). CONCLUSIONS VFA was weakly associated with 24 hour urine total quantities of sodium and creatinine. In corroboration with previous studies, high BMI increased the quantity and concentration of urinary solutes important to stone formation, including citrate, oxalate, phosphate, and uric acid. The prediction of uric acid stone formation by VFA and disproportionate burden of uric acid stones on those of white ethnicity observed agrees with prior research from our institution in a different subset of our patient population. This data suggest that both visceral and subcutaneous fat are integral to the development of stone disease and deserve further study. Single Models VFA Beta Standard Error p BMI Beta Standard Error p Combined Models VFA Beta Standard Error p BMI Beta Standard Error p Citrate 0.002 0.001 0.094 0.029 0.010 0.000 0.002 0.001 0.128 0.026 0.010 0.007 Oxalate † 0.002 0.001 0.044 0.030 0.010 0.002 0.002 0.001 0.060 0.028 0.010 0.004 Calcium* 0.002 0.001 0.043 0.006 0.010 0.556 0.002 0.001 0.076 0.003 0.010 0.765 Creatinine 0.004 0.001 0.001 0.033 0.009 0.000 0.004 0.001 0.000 0.029 0.009 0.001 Sodium 0.003 0.001 0.008 0.031 0.010 0.003 0.003 0.001 0.022 0.030 0.010 0.004 Phosphate 0.002 0.002 0.348 0.043 0.016 0.007 0.001 0.002 0.480 0.039 0.016 0.017 Uric Acid 0.001 0.001 0.478 0.027 0.010 0.006 0.000 0.001 0.790 0.030 0.010 0.004 Volume 0.002 0.001 0.154 0.003 0.010 0.796 0.001 0.001 0.215 0.002 0.010 0.877 Serum Uric Acid* 0.002 0.002 0.317 0.022 0.014 0.120 0.001 0.002 0.529 0.020 0.015 0.193 Citrate Concentration 0.000 0.001 0.904 0.021 0.010 0.030 0.000 0.001 0.894 0.020 0.010 0.049 Oxalate Concentration ‡ 0.000 0.001 0.822 0.023 0.010 0.021 0.000 0.001 0.737 0.022 0.010 0.028 Calcium Concentration* 0.001 0.001 0.621 0.008 0.009 0.386 0.001 0.001 0.635 0.007 0.010 0.482 Creatinine Concentration 0.001 0.001 0.443 0.024 0.010 0.015 0.001 0.001 0.278 0.022 0.010 0.026 Sodium Concentration 0.002 0.001 0.080 0.028 0.010 0.006 0.002 0.001 0.090 0.027 0.010 0.008 Phosphate Concentration -0.002 0.001 0.247 0.020 0.013 0.136 -0.002 0.002 0.247 0.020 0.014 0.159 Uric Acid Concentration -0.001 0.001 0.472 0.030 0.010 0.003 -0.001 0.001 0.361 0.032 0.010 0.002 * Adjusted for CKD † Adjusted for CAD ‡ Adjusted for HTN Multiple linear regression predicting quartiles of dependent variable. All models included age and sex, as well as any disease state observed to be significant on univariate analysis. Single models included either VFA or BMI, while combined models included both. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e273 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Ethan Fram More articles by this author Saman Moazami More articles by this author Mira Herman More articles by this author Ilir Agalliu More articles by this author Joshua Stern More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...