Inflammatory lipid mediators in Chronic Obstructive Pulmonary Disease: Association with the disease severity

<bold>Introduction:</bold> Chronic obstructive pulmonary disease (COPD) is the result of a chronic inflammation that fails to resolve. In contrast to other lung diseases, the inflammatory lipid mediators implicated in COPD have not been completely identified. We aimed to assess lipid mediators’ levels in COPD patients and control subjects and to analyze these mediators’ levels according to COPD severity and clinical parameters. <bold>Methods:</bold> We conducted a case-control study at our pulmonology department between Mars and September 2022 included 40 male patients, with confirmed COPD and in a stable condition. We included a group of 40 healthy smokers. Patients with COPD associated respiratory disease and receiving immunosuppressive treatment were excluded. The severity of the disease was assessed of the 2022 GOLD guidelines. Blood samples including polyunsaturated fatty acids, proinflammatory eicosanoids, specialized pro-resolving mediators (SPMs), C-reactive protein (CRP) levels as well as a forced spirometry were performed. <bold>Results:</bold> The mean age was 64 ±8 years in patients vs 59±7 years in controls. Eicosapentaenoic acid level was significantly higher in patients than in controls (p=0,021). The study of proinflammatory mediators showed a significantly higher levels of prostaglandins and leukotrienes in patients than in controls (p<10^-3). However, the analysis of SPMs showed no significant difference between the two groups. Protectin DX was significantly correlated with the number of hospitalizations for acute exacerbations per year (r=-0,38, p=0,015). The severity of bronchial obstruction was correlated with prostaglandin D2 and Leukotrien F4. <bold>Conclusion:</bold> Our study provides critical insights into COPD's underlying mechanisms.