Circulating mitochondrial signals during COPD exacerbation.

<bold>Introduction:</bold> Chronic obstructive pulmonary disease (COPD) exacerbation (ECOPD) alters the natural course of the disease. The stressed mitochondria release signals called mitokines (Humanin (HN), FGF-21, GDF-15, MOTS-c). Here, we aimed to evaluate the diagnostic and prognostic value of measuring serum mitokines at hospital admission in patients with ECOPD. <bold>Methods:</bold> 51 patients admitted to our hospital for ECOPD were included and followed for 1 year; in addition, 160 participants with stable COPD from our out-patient clinic were recruited as controls. <bold>Results:</bold> MOTS-c (p <. 001) and FGF-21 (p <. 001) levels were lower, and GDF-15 (p <. 001) levels were higher, in patients with ECOPD than stable COPD. In ROC curve analysis, MOTS-c (AUC 0.744, 95% CI 0.679–0.802, p <. 001) and GDF-15 (AUC 0.735, 95% CI 0.670–0.793, p <. 001) had the best discriminative power for ECOPD, with a diagnostic accuracy similar to that of C-RP (AUC 0.796 95% IC 0.735–0.848, p <. 001). FGF-21 (AUC 0.700, 95% CI 0.633–0.761, p <. 001) had lower diagnostic accuracy. In Cox regression analysis, MOTS-c (HR 3.441, CI95% 1.252–9.297, p =. 016) and HN (HR 2.661, CI95% 1.009–7.016, p =. 048) levels exceeding mean levels were independent risk factors for re-admission. <bold>Conclusion:</bold> MOTS-c and GDF15 levels have a diagnostic accuracy similar to C-RP for ECOPD. HN and MOTS-c independently predict future re-hospitalization.