Vitamin D deficiency during chronic obstructive pulmonary disease exacerbations

Abstract

BackgroundVitamin D deficiency is widespread and associated with increased risk of chronic diseases. The relation between chronic obstructive pulmonary disease (COPD) and vitamin D is complex owing to comorbidities, which are affected by vitamin D. Patients with low vitamin D showed higher risk for exacerbations.AimThe aim was to study the status of vitamin D in patients during exacerbation of chronic obstructive pulmonary disease (AECOPD).Patients and methodsThe study included 205 patients presented with AECOPD and 150 controls. Patients and controls were subjected to full clinical history and examination, pulmonary function testing, and vitamin D [hydroxyvitamin D, 25(OH)D] examination by Liaison 25 OH Vitamin D assay (direct competitive chemiluminescence immunoassay, DiaSorin Inc, Stillwater, Minnesota, USA) in serum. Symptom scoring was done using modified Medical Research Council (mMRC) and combined assessment of Global Initiative for Chronic Obstructive Lung Disease COPD classification, with division into groups A, B, C, and D. Data related to severity of exacerbation, site of care, and hospital days were gathered.StatisticsPearson’s χ2-test was used to compare the prevalence of categorical variables between patients with COPD and control groups. t-Test was used to compare differences in the levels of continuous variables between the two groups. R2-test was used to measure how close the data are to be fitted in the regression line.Results25(OH)D was significantly lower in patients with AECOPD than control group (mean: 39.5±32.5 vs. 56.3±43.7 nmol/l, P? 0.05). Vitamin D insufficiency (25–75 nmol/l) was significantly higher in patients than controls [115 (56.09%) patients vs. 51 (34%) controls, P<0.05]. Dyspnea score (mMRC) was higher in deficiency group (70.1% having two or more mMRC score) compared in insufficiency and sufficiency groups (51.3 and 51.5%, respectively). Patients with mild and moderate COPD (forced expiratory volume in first second >50%) showed higher 25(OH)D (69.4±23.1) than patients with severe and very severe COPD (forced expiratory volume in first second <50%) (47.4±28.3), with P value less than 0.05. Patients required hospitalization showed lower levels of 25(OH)D compared with patients treated at home (23±14.9 and 52±22.1, respectively), with P value less than 0.05. Hospital days were higher in deficiency group (3.78±3.51 days) compared with insufficiency group (1.68±2.33 days) or sufficiency group (1.3±1.7 days), with P value less than 0.05.ConclusionVitamin D is low in patients with COPD during AECOPD. The relationship is linear with lung function, disease severity groups and with previous exacerbation rate. Severe exacerbations requiring hospital admission and lengthy hospital stay were demonstrated in patients with low vitamin D.