Abstract: PO1542
Urinary Lithogenic Risk Profile in ADPKD Patients Treated with Tolvaptan
Session Information
- Cystic Kidney Diseases: Mechanisms, Genetics, and Treatment
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Genetic Diseases of the Kidneys
- 1001 Genetic Diseases of the Kidneys: Cystic
Authors
- Bargagli, Matteo, Università Cattolica del Sacro Cuore, Roma, Italy
- Dhayat, Nasser, Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Ferraro, Pietro Manuel, Università Cattolica del Sacro Cuore, Roma, Italy
- Fuster, Daniel G., Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
Background
Nephrolithiasis is a common health problem in autosomal dominant polycystic kidney disease (ADPKD) and significantly contributes to patient morbidity. Recently, Tolvaptan has been introduced for the treatment of ADPKD, but if it is associated with alterations of the urinary lithogenic risk profile remains unknown.
Methods
We conducted an analysis of participants enrolled in the Bern ADPKD registry, a prospective observational cohort study. 24 hour urine analyses were performed at baseline and then at yearly follow-ups. Relative supersaturation ratios for calcium oxalate, brushite and uric acid were calculated with the program EQUIL2. Unadjusted and multivariable mixed-effects linear regression models, adjusted for age, sex, body mass index, estimated glomerular filtration rate, net acid excretion and height-adjusted total kidney volume were used to assess the association of Tolvaptan with urinary parameters relevant for kidney stone formation. Maximum individual follow-up time was 3 years, median follow-up time 1.9 years and cumulative follow-up time was 169 years.
Results
125 participants (38 with and 87 without Tolvaptan treatment) were included in the analysis. In multivariable analysis, Tolvaptan treatment was associated (adjusted estimate of the difference Tolvaptan vs. no Tolvaptan; 95% CI) with lower urine relative supersaturation ratios for calcium oxalate (-0.56; -0.82 to -0.3, p < 0.001), brushite (-0.33; -0.54 to -0.11, p = 0.004) and uric acid (-0.62; -0.88 to -0.37, p < 0.001) and with increased urine citrate in mmol/mmol creatinine per day (0.25; 0.050-0.46, p = 0.02) and calcium in mmol/mmol creatinine per day (0.31; 0.090-0.53, p = 0.006) excretion. In addition, Tolvaptan treatment was associated with decreased net acid excretion in mEq/mmol creatinine per day (-0.54; -0.90 to -0.17, p = 0.004) and increased net gastrointestinal alkali absorption in mEq/mmol creatinine per day (0.57, 0.26-0.88; p < 0.001).
Conclusion
Tolvaptan treatment is associated with a significantly improved urinary lithogenic risk profile in ADPKD patients.