Associations Among 25-Hydroxyvitamin D Levels, Lung Function, and Exacerbation Outcomes in COPD: An Analysis of the SPIROMICS Cohort

Chest. 2020 Apr;157(4):856-865. doi: 10.1016/j.chest.2019.11.047. Epub 2020 Jan 17.


Background: The relationship between 25-hydroxyvitamin D (25-OH-vitamin D) and COPD outcomes remains unclear. Using the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS), we determined associations among baseline 25-OH-vitamin D and cross-sectional and longitudinal lung function and COPD exacerbations.

Methods: Serum 25-OH-vitamin D level was measured in stored samples from 1,609 SPIROMICS participants with COPD. 25-OH-vitamin D levels were modeled continuously and dichotomized as deficient (< 20 ng/mL) vs not deficient (≥ 20 ng/mL). Outcomes of interest included % predicted FEV1 (current and 1-year longitudinal decline) and COPD exacerbations (separately any and severe, occurring in prior year and first year of follow-up).

Results: Vitamin D deficiency was present in 21% of the cohort and was more prevalent in the younger, active smokers, and blacks. Vitamin D deficiency was independently associated with lower % predicted FEV1 (by 4.11%) at enrollment (95% CI, -6.90% to -1.34% predicted FEV1; P = .004), 1.27% predicted greater rate of FEV1 decline after 1 year (95% CI, -2.32% to -0.22% predicted/y; P = .02), and higher odds of any COPD exacerbation in the prior year (OR, 1.32; 95% CI, 1.00-1.74; P = .049). Each 10-ng/mL decrease in 25-OH-vitamin D was associated with lower baseline lung function (-1.04% predicted; 95% CI, -1.96% to -0.12% predicted; P = .03) and increased odds of any exacerbation in the year before enrollment (OR, 1.11; 95% CI, 1.01-1.22; P = .04).

Conclusions: Vitamin D deficiency is associated with worse cross-sectional and longitudinal lung function and increased odds of prior COPD exacerbations. These findings identify 25-OH-vitamin D levels as a potentially useful marker of adverse COPD-related outcomes.

Keywords: COPD; COPD epidemiology; COPD exacerbations; lung function; vitamin D.

Publication types

  • Multicenter Study
  • Observational Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Biomarkers / blood
  • Correlation of Data
  • Disease Progression
  • Female
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Outcome Assessment, Health Care
  • Prevalence
  • Pulmonary Disease, Chronic Obstructive* / blood
  • Pulmonary Disease, Chronic Obstructive* / diagnosis
  • Pulmonary Disease, Chronic Obstructive* / epidemiology
  • Pulmonary Disease, Chronic Obstructive* / physiopathology
  • Respiratory Function Tests* / methods
  • Respiratory Function Tests* / statistics & numerical data
  • Symptom Flare Up
  • United States / epidemiology
  • Vitamin D / analogs & derivatives*
  • Vitamin D / blood
  • Vitamin D Deficiency* / diagnosis
  • Vitamin D Deficiency* / epidemiology


  • Biomarkers
  • Vitamin D
  • 25-hydroxyvitamin D