Context: The relationship between vitamin D status and pulmonary function has not been investigated for an East Asian population.
Objective: The aim of the present study was to examine the relationship of serum 25-hydroxyvitamin D [25(OH)D] with lung function in Korean adults.
Design and setting: The analysis used data from the Korea National Health and Nutrition Examination Survey (KNHANES), a cross-sectional survey of Korean civilians, conducted from 2008 to 2010.
Participants: A total of 10 096 people aged 19 years and older were selected from 16 administrative districts in South Korea.
Main outcome measures: Serum 25(OH)D levels with lung function [forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC)].
Results: Serum 25(OH)D concentration was positively associated with lung function after controlling for age, sex, height, and season. For FEV1 and FVC, the differences between top and bottom quartiles in 25(OH)D were 51 mL (SE, 17 mL, P trend <.001) and 58 mL (SE, 20 mL, P trend <.005) greater volume, respectively. Association of serum 25(OH)D with FEV1 and FVC was only slightly attenuated after adjustment for body mass index, lifestyle and socioeconomic factors, and respiratory illness. The subjects with a history of pulmonary tuberculosis showed a much higher increase in FEV1; the difference between top and bottom quartiles in 25(OH)D was 229 mL (SE, 87 mL, P trend <.01).
Conclusion: Serum 25(OH)D levels have a positive correlation with pulmonary function. This relationship appears prominent in subjects with susceptibility to pulmonary tuberculosis.