Vitamin D3 – does it correlate with exercise tolerance in stable COPD?

Abstract

Background: Though the classic function of vitamin D₃ in skeletal health is established, but its new role has been discovered in tissues and organs other than bones. Vitamin D₃ deficiency has been found in patients with various morbid conditions, such as cardiovascular diseases, autoimmune diseases, infectious diseases, Diabetes mellitus and malignancies including respiratory ailments.

Objectives: This cross sectional study was designed to evaluate the status of this fat soluble vitamin D₃ and its correlation with exercise tolerance in stable COPD patients.

Methods: For this purpose, 47 male, smoker (>4 pack years), stable (who has not experienced any acute exacerbation, hospitalizations, urgent care visits, or changes in routine medications within 4 weeks prior to study), COPD patients (post bronchodilator FEV₁/FVC<0.70; duration >4 years) of >40 years of age, were selected from the Out Patient Department of National Institute of Diseases of Chest and Hospital (NIDCH), Dhaka. For the assessment of vitamin D₃ status, their serum 25-hydroxycholecalciferol [25(OH)D], for exercise tolerance, 6 min walk distance [6MWD; by 6 min walk test], peripheral capillary oxygen saturation (SpO2) [by pulse oximetry], level of dyspnea and fatigue [by Modified BORG scale], were measured. The data were expressed as percentage and mean ±SEM and were statistically analyzed by Pearson’s correlation coefficient test, where p<0.05 was accepted as significant.

Results: Out of 47 stable COPD patients, 46 (97.8%) were with serum 25(OH) D < 30 ng/ml. In addition, 6MWD was positively (p£0.05) and dyspnea (p£0.001) along with fatigue (p£0.05) score were negatively correlated with serum 25(OH)D level in these stable COPD patients.

Conclusion: This study result concluded that, majority patients with stable COPD had D3 deficiency and this D₃ deficiency showed significant correlation with decrement of exercise tolerance.

J Bangladesh Soc Physiol. 2019, June; 14(1): 14-20