IL-33 as a biomarker for disease severity in COPD with lung cancer comorbidity.

OBJECTIVE

To investigate the differences in peripheral blood levels of interleukin-1β (IL-1β), IL-6, IL-17, and IL-33 between patients with chronic obstructive pulmonary disease (COPD) and lung cancer (Comorbidity Group) and those with COPD alone (COPD Group), as well as to explore their clinical significance.

METHODS

Samples were collected from 133 patients with both COPD and lung cancer (Comorbidity Group) and 91 patients with COPD alone (COPD Group), diagnosed at Affiliated Hospital of Inner Mongolia Medical University between January 2022 and January 2024. Baseline data from both groups were analyzed, and peripheral blood levels of IL-1β, IL-6, IL-17, and IL-33 were measured using enzyme-linked immunosorbent assay (ELISA). The levels of these inflammatory cytokines were compared between the two groups to assess their correlation with disease severity.

RESULTS

Significant differences were observed between the Comorbidity Group and the COPD Group in terms of age (P<0.001), sex (P=0.012), duration of COPD (P=0.001), smoking history (P=0.006), glucocorticoid treatment (P=0.014), and GOLD Staging (P<0.001). IL-1β was positively correlated with RV/TLC (P=0.036), and IL-17 with FEV1 (P=0.027) in both groups. IL-6 was positively correlated with TLC in the Comorbidity Group (P=0.021). In the COPD Group, IL-33 was negatively correlated with FEV1 (P<0.001), FVC (P=0.001), FEV1/FVC (P<0.001), RV (P<0.001), and RV/TLC (P<0.001), and positively correlated with GOLD Staging (P=0.046). Multivariate logistic regression identified smoking history (P=0.045, OR=2.891), GOLD staging (P=0.028, OR=0.363), IL-33 (P=0.001, OR=27.369), FEV1/FVC (P=0.012, OR=4.291), RV (P=0.002, OR=5.429), and RV/TLC (P=0.002, OR=6.113) as independent factors distinguishing patients with comorbid COPD and lung cancer from those with COPD alone. Interaction analysis revealed no significant interaction between IL-33 and other risk factors.

CONCLUSION

IL-33 levels were significantly higher in patients with comorbid COPD and lung cancer than in those with COPD alone. IL-33 was negatively correlated with lung function and positively correlated with GOLD Staging, suggesting its potential as a biomarker for disease severity.