biostudies-literatureBansal NNCATSMichigan Institute for Clinical and Health ResearchNational Center for Research ResourcesClinical and Translational Science Collaborative of ClevelandNCATS NIH HHSJohns Hopkins UniversityNCRR NIH HHSNational Institute of Diabetes and Digestive and Kidney DiseasesUniversity of MarylandNational Institutes of HealthNational Center for Advancing Translational Sciences (NIHNIHNIDDK NIH HHSUniversity of Illinois at ChicagoPerelman School of Medicine at the University of PennsylvaniaKaiser PermanenteClinical and Translational Research in Cardiometabolic DiseasesNIGMS NIH HHS1598-1607https://www.ebi.ac.uk/biostudies/studies/S-EPMC6933450biostudies-literatureUnknown4(11)<h4>Introduction</h4>Assessment of impaired vitamin D metabolism is limited by lack of functional measures. CYP24A1-mediated vitamin D clearance, calculated as the ratio of serum 24,25-dihydroxyvitamin D3 to 25-hydroxyvitamin D3 (the vitamin D metabolic ratio, VDMR), is induced by 1,25-dihydroxyvitamin D and may assess tissue-level activity. We tested associations of the VDMR with risks of death and progression to end-stage renal disease (ESRD) in patients with chronic kidney disease (CKD).<h4>Methods</h4>We studied participants from the Chronic Renal Insufficiency Cohort (CRIC), which included a random subset of 1080 CRIC participants plus additional participants who experienced ESRD or died (case cohort study design). Serum 24,25-dihydroxyvitamin D3 and 25-hydroxyvitamin D3 was measured Kidney international reportsVitamin D Metabolic Ratio and Risks of Death and CKD Progression.PMC6933450U01 DK061021P20 GM109036U01DK061028U01 DK060990U01 DK061022UL1RR029879M01 RR013987UL1TR000433GCRC M01 RR-16500U01DK061021U01 DK061028UL1 RR029879UL1 TR000433U01DK060990U01DK061022UL1 TR000439U24 DK060990M01 RR016500R01DK099199U01 DK060902UL1TR-000424UL1 RR024131U01DK060963UL1TR000003U01DK060984UL1 TR000003UL1RR-024131U01DK060902U01 DK060963UL1 TR002548UL1 TR000424U01 DK060984U01 DK060980U01DK060980R01 DK072231UL1TR000439R01 DK099199Feldman HIsakova TKusek JWGo ASXie DFeldman HICRIC Study InvestigatorsTownsend RRRao PSRobinson-Cohen Cde Boer IHLash JPWolf MZelnick LHe JKatz RKusek JLash JRahman MHoofnagle AKestenbaum BDenburg MAppel LJLeonard MAppel LBansal NfalseVitamin D Metabolic Ratio and Risks of Death and CKD Progression.<h4>Introduction</h4>Assessment of impaired vitamin D metabolism is limited by lack of functional measures. CYP24A1-mediated vitamin D clearance, calculated as the ratio of serum 24,25-dihydroxyvitamin D3 to 25-hydroxyvitamin D3 (the vitamin D metabolic ratio, VDMR), is induced by 1,25-dihydroxyvitamin D and may assess tissue-level activity. We tested associations of the VDMR with risks of death and progression to end-stage renal disease (ESRD) in patients with chronic kidney disease (CKD).<h4>Methods</h4>We studied participants from the Chronic Renal Insufficiency Cohort (CRIC), which included a random subset of 1080 CRIC participants plus additional participants who experienced ESRD or died (case cohort study design). Serum 24,25-dihydroxyvitamin D3 and 25-hydroxyvitamin D3 was measured 2019-01-01T00:00:00Z2019 Nov2025-04-04T22:34:43.661Z2020-05-22T01:18:34ZS-EPMC69334503189100110.1016/j.ekir.2019.08.014