Vitamin D deficiency is associated with respiratory symptoms and airway wall thickening in smokers with and without COPD: a prospective cohort study.
Ghosh AJ, Moll M, Hayden LP, Bon J, Regan E, Hersh CP. Vitamin D deficiency is associated with respiratory symptoms and airway wall thickening in smokers with and without COPD: a prospective cohort study. BMC Pulm Med. 2020 May 04; 20(1):123.