Increasing use of vitamin D supplementation in the chronic renal insufficiency cohort study.

Journal Article (Journal Article;Multicenter Study)

OBJECTIVE: This study examined rates and determinants of vitamin D supplementation among Chronic Renal Insufficiency Cohort (CRIC) participants and determined the association between dose and 25-hydroxyvitamin D (25(OH)D) level. The 2010 Institute of Medicine Report noted a significant increase in vitamin D supplementation in the general population, but use in chronic kidney disease (CKD) is unknown. METHODS: CRIC is a multicenter prospective observational cohort study of 3,939 participants with a median baseline age of 60 and an estimated glomerular filtration rate (eGFR) of 42.1 mL/minute per 1.73 m2. Of the cohort, 54.9% was male, 42.1% were Black, and 48.4% were diabetic. Multivariable logistic generalized estimating equations were used to examine determinants of supplementation use assessed annually between 2003 and 2011. Cross-sectional linear regression models, based on a subset of 1,155 participants, assessed associations between supplement dose and 25(OH)D level, measured by high-performance liquid chromatography coupled with tandem mass spectrometry. RESULTS: The proportion of participants reporting supplement use increased (P < .0001), from 10% at baseline to 44% at 7-year follow-up visits. This was largely due to initiation of products containing only ergocalciferol or cholecalciferol. The odds of supplementation were greater in older, female, non-Black, married participants with greater education and lower body mass index. Among participants taking supplementation, dose was positively associated with 25(OH)D level, adjusted for race, season, diabetes, dietary intake, eGFR, and proteinuria. Only 3.8% of non-Black and 16.5% of Black participants taking a supplement were deficient (<20 ng/mL), whereas 22.7% of non-Black and 62.4% of black participants not reporting supplement use were deficient. CONCLUSIONS: Vitamin D supplementation rates rose significantly among CRIC participants over 7 years of follow-up and were associated with greater serum 25(OH)D levels. Studies of vitamin D levels on clinical outcomes in CKD and future vitamin D interventional studies should consider these changes in supplementation practices.

Full Text

Duke Authors

Cited Authors

  • Mariani, LH; White, MT; Shults, J; Anderson, CAM; Feldman, HI; Wolf, M; Reese, PP; Denburg, MR; Townsend, RR; Lo, JC; Cappola, AR; Carlow, D; Gadegbeku, CA; Steigerwalt, S; Leonard, MB; CRIC Study Investigators,

Published Date

  • May 2014

Published In

Volume / Issue

  • 24 / 3

Start / End Page

  • 186 - 193

PubMed ID

  • 24613295

Pubmed Central ID

  • PMC4023561

Electronic International Standard Serial Number (EISSN)

  • 1532-8503

Digital Object Identifier (DOI)

  • 10.1053/j.jrn.2014.01.015


  • eng

Conference Location

  • United States