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Age and vitamin D levels may affect symptom burden in chronic obstructive pulmonary disease (COPD). We used the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) to determine independent associations between vitamin D levels and COPD symptoms in different age strata.

Age-Dependent Associations Between 25-Hydroxy Vitamin D Levels and COPD Symptoms: Analysis of SPIROMICS