Does vitamin D deficiency worsen the clinical and functional parameters of stable chronic obstructive pulmonary disease patients?

Introduction There is not much data about the effect of deficient vitamin D on stable chronic obstructive pulmonary disease (COPD) patients and its relation to the disease severity. Objective The aim was to measure the serum level of 25-hydroxy (OH) vitamin D in stable COPD patients, and to assess its relation to COPD severity and functional parameters. Patients and methods A prospective study that was carried out at Chest Department, Kasr El-Aini Hospital, Cairo University. It was carried out on 70 male individuals: 50 stable COPD patients and 20 healthy individuals. All persons were subjected to history taking, clinical examination, 6 min walk test (6MWT), spirometry, and measurement of 25(OH) vitamin D serum level. Results Our results showed a deficiency of vitamin D in 37 (74%) of the COPD patients. It showed a significant lower level of 25(OH) vitamin D in COPD cases who were severe and very severe, compared with those who were mild and moderate ones (P=0.017). There was also a positive significant correlation between vitamin D level and 6 min walk distance, basal oxygen saturation, post-6MWT oxygen saturation, and forced expiratory volume in the first second predicted, and an inverse correlation with basal heart rate and post-6MWT heart rate. Conclusion The study highlights the value of measurement of vitamin D level in COPD, as a potential therapeutic agent. Vitamin D serum level showed low values in COPD cases compared with healthy ones and was correlated significantly to forced expiratory volume in the first second predicted.