Association of Serum Level of 25-Hydroxy Vitamin D Deficiency and Pulmonary Function in Healthy Individuals.

Background: Besides the extensive regulatory role in growing number of biologic processes, vitamin D has been recently considered essential for lungs function as well as protective against exacerbation of chronic obstructive pulmonary diseases. We assessed the correlation between vitamin D serum levels with pulmonary function in healthy individuals.

Methods: In a cross-sectional study, healthy volunteer ( n = 92) participants underwent the following laboratory procedures: a blood test, a 24-hour urine collection test, and the serum level of 25-hydroxy vitamin D before undergoing spirometry. Linear correlation coefficient was calculated to detect the association between serum level of 25-hydroxy vitamin D and pulmonary volumes.

Results: The mean age of participants was 39.95 ± 9.98 years. 48% of participants showed different levels of 25-hydroxy vitamin D deficiency. We recognized a consistent direct positive correlation between serum levels of 25-hydroxy vitamin D and lung function volumes. The coefficient for forced vital capacity, forced expiratory volume in 1 second, forced expiratory flow 25-75%, and forced expiratory volume in 1 second/forced vital capacity ratio were 0.610, 0.509, 0.454, and 0.551, respectively.

Conclusions: Our findings suggest correlation between higher serum levels of 25-hydroxy vitamin D and improved pulmonary function. Accordingly, supplemental vitamin D might significantly improve treatment response.