Abstract: PO0415
Association of Urine Findings with Metabolic Syndrome (met-s) Traits in Patients with Nephrolithiasis
Session Information
- Calcified Tissues in Kidney Diseases
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Bone and Mineral Metabolism
- 402 Bone and Mineral Metabolism: Clinical
Authors
- Hood, Virginia L., University of Vermont College of Medicine, Burlington, Vermont, United States
- Mulligan, Carley, University of Vermont College of Medicine, Burlington, Vermont, United States
- de Waal, Desiree, University of Vermont Medical Center, Burlington, Vermont, United States
- Callas, Peter W., University of Vermont, Burlington, Vermont, United States
- Sternberg, Kevan M., University of Vermont College of Medicine, Burlington, Vermont, United States
Background
Met-s is a health concern related to lifestyle habits including acidogenic and high protein diets. The odds of nephrolithiasis increases with an increasing number of met-s traits. Prior studies have shown relationships among the number of met-s traits and decreasing urine pH and other acid excretion markers. We evaluated associations of urine factors including acid excretion and stone composition with the number of met-s traits in a large cohort of stone-forming patients.
Methods
A retrospective review was performed of 24-hour urine studies (Litholink, Chicago, Il) from patients seen in Urology and Nephrology divisions, UVMMC July 2009 to December 2018. Patients <18 years and those with improper collections based on creatinine/kg were excluded. Patient variables, laboratory values, associated diagnoses, and medications were identified within 6 months of urine collection and 1 year of kidney stone composition. Four groups based on the number (0, 1, 2, 3-4) of met-s traits (hypertension, obesity, dyslipidemia, diabetes) were evaluated. Trends across groups were tested using linear contrasts in analysis of variance.
Results
1250 unique patients, 49% F, 703 with stone composition met criteria for inclusion. Met-s groups n were 0=509, 1=381, 2=203, 3+4=157. There was no difference or trends among the groups for urine volume, calcium or citrate. There was a significant trend p<0.001 for increasing number of met-s traits with decreasing urine pH and SS calcium phosphate (CaP) and increasing age, weight, protein intake, urine uric acid (UA), SS UA, oxalate, sodium, potassium, phosphorus, urea nitrogen, chloride, estimated net acid excretion and p<0.05 for sulfate (S), ammonium, magnesium. When adjusted for age and protein intake the trend remained significant only for urine pH and a reversed trend for S. There was a significant trend for more UA and fewer predominately CaP stones in those with more met-s traits.
Conclusion
High protein intake accounted for most of the difference in urinary markers of stone risk except low urine pH. The latter facilitates more UA and less CaP contribution to stone composition. Future studies could determine if changing diet can reduce risk for stones in met-s
Funding
- Clinical Revenue Support