Association of Severe Vitamin D Deficiency with Hospitalization in the Previous Year in Hospitalized Exacerbated COPD Patients

Abstract

Boyu Li,1,* Meishan Liu,2,* Ying Wang,2 Hong Zhang,2 Lingling Xuan,1 Kewu Huang,2 Zhuoling An1 1Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, People’s Republic of China; 2Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University, Beijing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Kewu Huang; Zhuoling An, Beijing Chao-Yang Hospital, Capital Medical University, 8 Gongtinan Road, Beijing, People’s Republic of China, Tel/Fax [phone] ; Tel/Fax [phone], Email [email protected]; [email protected]: Vitamin D deficiency (VDD, 25-hydroxyvitamin D < 20 ng/mL) has been reported associated with exacerbation of chronic obstructive pulmonary disease (COPD) but sometimes controversial. Research on severe vitamin D deficiency (SVDD, 25-hydroxyvitamin D < 10 ng/mL) in exacerbation of COPD is limited.Patients and Methods: We performed a retrospective observational study in 134 hospitalized exacerbated COPD patients. 25-hydroxyvitamin D was modeled as a continuous or dichotomized (cutoff value: 10 or 20 ng/mL) variable to evaluate the association of SVDD with hospitalization in the previous year. Receiver operator characteristic (ROC) analysis was performed to find the optimal cut-off value of 25-hydroxyvitamin D.Results: In total 23% of the patients had SVDD. SVDD was more prevalent in women, and SVDD group tended to have lower blood eosinophils counts. 25-hydroxyvitamin D level was significantly lower in patients who were hospitalized in the previous year (13.6 vs 16.7 ng/mL, P = 0.044), and the prevalence of SVDD was higher (38.0% vs 14.3%, P = 0.002). SVDD was independently associated with hospitalization in the previous year [odds ratio (OR) 4.34, 95% CI 1.61– 11.72, P = 0.004] in hospitalized exacerbated COPD patients, whereas continuous 25-hydroxyvitamin D and VDD were not (P = 0.1, P = 0.9, separately). The ROC curve yielded an area under the curve of 0.60 (95% CI 0.50– 0.71) with an optimal 25-hydroxyvitamin D cutoff of 10.4 ng/mL.Conclusion: SVDD probably showed a more stable association with hospitalization in the previous year in hospitalized exacerbated COPD patients. Reasons for lower eosinophil counts in SVDD group needed further exploration.Keywords: association, vitamin D, severe deficiency, hospitalization for exacerbation, COPD

Keywords

• association
• vitamin d
• severe deficiency
• hospitalization for exacerbation
• copd