Determinants of serum 25 hydroxyvitamin D levels in a nationwide cohort of blacks and non-Hispanic whites

Cancer Causes Control. 2010 Apr;21(4):501-11. doi: 10.1007/s10552-009-9481-1. Epub 2009 Dec 11.

Abstract

Objective: To develop algorithms predicting serum 25 hydroxyvitamin D [s25(OH)D] for a large epidemiological study whose subjects come from large geographic areas, are racially diverse and have a wide range in age, skin types, and month of blood sample collection. This will allow a regression calibration approach to determine s25(OH)D levels replacing the more costly method of collection and analysis of blood samples.

Study design and setting: Questionnaire data from a subsample of 236 non-Hispanic whites (whites) and 209 blacks from the widely dispersed Adventist Health Study-2 (n = 96,000) were used to develop prediction algorithms for races separately and combined. A single blood sample was collected from each subject, at different times throughout the year.

Results: Models with independent variables age, sex, BMI, skin type, UV season, erythemal zone, total dietary vitamin D intake, and sun exposure factor explained 22 and 31% of the variance of s25(OH)D levels in white and black populations, respectively (42% when combined). UV season and erythemal zone determined from measured UV radiation produced models with higher R (2) than season and latitude.

Conclusion: Combining races with a term for race and using variables with measured UV radiation capture the variance in s25(OH)D levels better than analyzing races separately.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Alcohol Drinking
  • Black People / statistics & numerical data*
  • Black or African American
  • Canada
  • Cohort Studies
  • Dietary Supplements
  • Erythema / etiology
  • Female
  • Humans
  • Male
  • Multivariate Analysis
  • Regression Analysis
  • Risk Factors
  • Seasons
  • Skin Pigmentation / radiation effects
  • Smoking
  • Surveys and Questionnaires
  • Ultraviolet Rays / adverse effects
  • United States
  • Vitamin D / administration & dosage
  • Vitamin D / analogs & derivatives*
  • Vitamin D / blood
  • White People / statistics & numerical data*

Substances

  • Vitamin D
  • 25-hydroxyvitamin D