A study to assess the relationship between vitamin D3 levels and the risk of acute exacerbation in patients with chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is one of the top three causes of mortality worldwide. Vitamin D deficiency in COPD has been associated with poor lung function and decreased muscle power, which further increases the risk of exacerbations. The role of vitamin D in preventing acute exacerbations of COPD has conflicting results in the literature. Hence, we planned this study to assess the relationship between vitamin D3 levels and the risk of acute exacerbations among COPD patients in a tertiary care center in north India. This was a prospective randomized control trial that was performed on 100 consecutive stable COPD patients attending the Department of Respiratory Medicine at Maharishi Markandeshwar Medical College and Hospital, Solan, India. The patients with subnormal vitamin D3 levels (i.e., less than 30 ng/mL) were divided into the intervention and control groups. Baseline demographic profiles, lung function, COPD assessment test (CAT) score, modified Medical Research Council grade and chest radiology were performed and repeated after 12 months in all these patients. All these parameters were recorded and compared with the baseline values obtained at the beginning of the study. Out of 100 subjects, 96 had vitamin D deficiency, of which 48 were assigned to the intervention group and 48 to the control group. Among the 100 subjects, 74 (74%) were males and 26 (26%) were females, with a mean age of 66.9±9.4 years. The mean vitamin D level was 14.71±6.69 in these 96 patients. The vitamin D level improved after 3 months of supplementation to the mean level of 45.56±16.18 in the intervention group. Vitamin D supplementation was positively correlated with a decrease in the rate of acute exacerbations in the intervention group in terms of reduction in mean CAT score (4.17 in intervention and 1.43 in non-interventional group, p<0.001), number of acute exacerbations (1.7 in intervention and -1.05 in non-interventional group, p<0.001), and number of emergency visits (p=0.0121) during the 9-month period after attainment of a normal vitamin D level. Vitamin D supplementation plays a key role in COPD patients with D3 hypovitaminosis in decreasing COPD acute exacerbations, improving the CAT score, and reducing the number of emergency visits.