Expression of Irisin in Pulmonary Rehabilitation of COPD Patients and Its Prognostic Value

<bold>Objective</bold> Analysis of irisin expression in the serum of COPD patients in order to explore the alteration of irisin in COPD before and after PR (pulmonary rehabilitation) treatment and analyze the prognostic value of irisin in COPD with acute exacerbations. <bold>Methods</bold> A total of 68 COPD outpatients and 35 healthy participants were admitted. ELISA was applied to detect the expression of irisin in the serum of the patients and then the difference of irisin in COPD patients and the healthy control group and the alteration of it before and after PR treatment were compared. The correlation analysis was used to analyze the relationship between irisin and 6MWD and IL-6 and K-M survival curve was utilized to differ the one-year cumulative risk of acute exacerbation-free risk ratio between the low irisin expression group and the high irisin expression group. <bold>Results</bold> 1. The expression of irisin in the serum of COPD was lower than healthy controls (P<0.005). 2. The concentration of irisin in COPD after PR treatment was higher than that before PR treatment (P<0.05). 3. The level of Irisin in COPD was positively correlated with the 6MWD (P<0.05) and negatively related with IL-16 level (P<0.05). 4. K-M survival curve demonstrated that cumulative acute exacerbation-free rate in the low-level and high-level irisin groups was 30.0% VS 68.12%, respectively (P<0.05). <bold>Conclusions</bold> The expression of Irisin in the serum of COPD was lower than the healthy control and its level elevated after PR treatment; The reduction of irisin was a poor prognostic indicator for acute exacerbations in patients with COPD.