Association Of Vitamin D With The Quality Of Life And Inflammatory Factors In COPD

Object The purpose of this study was to investigate the prevalence of vitamin D deficiency in patients with COPD,to detect the impact of vitamin D deficiency on the quality of life in COPD,to detect the levels of25-(OH)D, INF-γ and IL-17in COPD and to analyze the correlations of these indices.Materials and Methods The research design was a case-control study.36COPD patients of acute exacerbations (AECOPD group),38outpatients of stable COPD(stable COPD group) and30healthy subjects(control group) were collected in our hospital from December2011to March2012.The serum levels of25-(OH)D, INF-γ and IL-17were measured in all subjects by the ELISA(double antibody sandwich method).According to the criteria of vitamin D deficiency in the "Evaluation, Treatment and Prevention of Vitamin D Deficiency:an Endocrine Society Clinical Practice Guideline" which was promulgated by the Endocrine Society in June2011, the cases of vitamin D deficiency were diagnosed among three groups and then the prevalence of vitamin D deficiency was calculated and compared. CAT scores were measured and compared in AECOPD group and stable COPD group and the relationship between25-(OH)D and CAT scores was analyzed. The levels of25-(OH)D, INF-γ and IL-17were compared among three groups and the correlations among25-(OH)D, INF-γ and IL-17were analyzed in AECOPD group and stable COPD group.Results(1) There were significant differences among three groups about the level of25-(OH)D (P<0.05).Of36patients in AECOPD group,19were diagnosed with vitamin D deficiency,the prevalence of vitamin D deficiency was52.78%and mean25-(OH)D level was21.99±13.07ng/ml in this group.Of38patients in stable COPD group,15were diagnosed with vitamin D deficiency, the prevalence of vitamin D deficiency was39.47%and mean25-(OH)D level was33.33±21.90ng/ml in this group. The total prevalence of vitamin D deficiency was45.95%in COPD subjects. Of30patients in control group,5were diagnosed with vitamin D deficiency, the prevalence of vitamin D deficiency was16.67%and mean25-(OH)D level was76.45±55.35ng/ml in this group. There was difference in the prevalence of vitamin D deficiency among three groups (χ2=9.115, v=2, P=0.010). There was significant difference in the prevalence of vitamin D deficiency between AECOPD group and control group (P=0.003) and the prevalence of vitamin D deficiency was higher in AECOPD group. There was difference in the prevalence of vitamin D deficiency between stable COPD group and control group (P=0.042) and the prevalence of vitamin D deficiency was higher in stable COPD group. There was no significant difference in the prevalence of vitamin D deficiency between AECOPD group and stable COPD group (P=0.254).(2) The significant differences were found between AECOPD group and stable COPD group in the25-(OH)D level (P=0.011) and CAT scores (P＜0.001). In the AECOPD group,the correlation analysis showed that the25-(OH)D level was negatively correlated with CAT scores (r=-0.603, P＜0.001). In the stable COPD group,the correlation analysis showed that the25-(OH)D level was negatively correlated with CAT scores (r=-0.549, P＜0.001)(3) There were significant differences among three groups about the levels of INF-γ and IL-17(P＜0.001)(4) In AECOPD group,the correlation analysis showed that the25-(OH)D level was negatively correlated with the INF-γlevel (r=-0.667, P<0.001) and the25-(OH)D level was negatively correlated with the IL-17level (r=-0.702, P＜0.001).In stable COPD group,the correlation analysis showed that the25-(OH)D level was negatively correlated with the INF-γ level (r=-0.769, P＜0.001) and the25-(OH)D level was negatively correlated with the IL-17level (r=-0.683, P＜0.001)Conclusion(1) Vitamin D deficiency is highly prevalent to COPD patients.(2) Vitamin D deficiency has a negative impact on the life quality of patients with COPD. (3) Vitamin D may affect the expression levels of INF-y and IL-17to participate in the inflammatory reaction of COPD.