The relationship between vitamin D levels and systemic inflammation in patients with COPD

Introduction and Objective: Although the relationship between deficiency of Vitamin D and systemic inflammation have been demonstrated in various chronic diseases, this relationship has not been revealed in chronic obstructive pulmonary disease (COPD) yet. In this study, it is aimed to evaluate the relationship between systemic inflammation and vitamin D levels in patients with stable COPD. Materials and Methods: In this study, fifty patients with stable COPD, according to GOLD 2009-2011, who were older than forty years, and either current smoker or ex smoker, whom admitted to the Department of Chest Disease, Cukurova University, and fifty one healthy controls, with similiar age and gender, were recruited between July-October 2011. After demographic characteristics of patients with COPD and healthy controls were recorded, pulmonary function tests and 6-minute walking test (6MWT) were performed in all patients. And, also, BODE index, physical activity level and mMRC dyspnea scale were recorded. Then, peripheral venous blood samples were obtained for the measurement of level of serum 25-OH Vitamin-D3, and levels of IL-1, IL-6, IL-8, TNF-Alpha, CRP and fibrinojen, for evaluation of systemic inflammation in both stable COPD patients and healthy controls. Results: The prevalance of Vitamin D deficiency (<20 ng/ml) was found more frequent in patients with COPD than the healthy controls (46% vs 11. 5%, p<0. 001). Mean serum vitamin D level in COPD patients was significantly lower than healthy controls.(19. 8±6. 2 vs 28. 4±8. 1 ng/ml, p<0. 001). When the levels of serum inflammatory markers were compared; IL-6, CRP, fibrinogen and AAT levels in patients with stable COPD were found higher than healthy controls (p<0.05), while IL-1, IL-8 and TNF-alpha levels were found similar in both groups (p>0.05). When patients with stable COPD were compared according to with or without deficiency of vitamin D, mMRC dyspnea scores was found lower (1. 4±1. 1 vs. 2. 3±1. 3, p<0. 05), BODE index was found higher (4. 1±2. 1 vs. 2. 3±2. 6, p<0. 05), and physical activity levels and 6-minute walking test was similar in patients with vitamin D deficiency. According to GOLD 2011 classification, as the severity of COPD increased, the deficiency of vitamin D was found higher. When the patients with COPD were compared according to systemic inflammatory markers, no significant difference was found between the patients with or without deficiency vitamin D. And, also, no significant correlation was revealed beetween serum vitamin D levels and systemic inflammatory markers. Discussion: In this study, it is demonstrated that deficiency vitamin D was more frequent in patients with COPD, but any significant relationship was not found between serum vitamin D levels and systemic inflammatory markers. Further large clinical trials are needed to evaluate the impact of level of vitamin D on the systemic inflammation in patients with COPD.