Background: This study examined the association between serum 25-hydroxyvitamin D (25(OH)D) and pulmonary function, among Korean adults, from 2010 to 2014.
Methods: The data were obtained from the fifth Korea National Health and Nutrition Examination Survey (KNHANES 5), and the first and second year (2013-2014) of KNHANES 6. The study population comprised 14,378 individuals. The variable of interest was serum 25(OH)D, and the dependent variable, pulmonary function.
Results: All people with vitamin D levels below 30 ng/ml had lower lung functions, which was significant in lower forced expiratory volume in the first second (FEV1) (serum 25(OH)D < 10 ng/ml, 20 to <30 ng/ml: P = .001, 10 to <20 ng/ml: P = 0) and forced vital capacity (FVC) (serum 25(OH)D level <10 ng/ml: P = .01, 10 to < 20 ng/ml: P = .001, 20 to <30 ng/ml: P = .008). The lower the serum 25(OH)D, the lower the levels of FEV1 in men and this was significant. (serum 25(OH)D < 10 ng/ml: P = .007, 10 to <20 ng/ml: P = .002, 20 to <30 ng/ml: P = .007). The values of FEV1 and FVC were lower in people aged 50-69 years when vitamin D was lower than 30 ng/ml which were all significant. Among participants with BMI values < 23 kg/m2, lower vitamin D levels were significantly associated with lower pulmonary function.
Conclusions: We found a significant association between serum 25(OH)D and pulmonary function, and this was related to sex, age and body mass index.
Keywords: Epidemiology; Pulmonary function; Serum 25-hydroxyvitamin D.
Copyright © 2018. Published by Elsevier Ltd.