Lipoprotein-associated phospholipase A2 and its possible association with COPD development: a case-control study.

Background: The association of lipoprotein-associated phospholipase A2 (Lp-PLA2) with various cardiovascular events has been well-established. However, the exploration of its potential involvement in Chronic obstructive pulmonary disease (COPD) is currently limited. Therefore, our study aims to examine the relationship between Lp-PLA2 and pulmonary conditions, including emphysema, obstructive ventilatory dysfunction as well as small airway dysfunction, to provide further evidence of a possible association with COPD development.

Methods: Using data from the Southwest Hospital Health Management Center, spanning January 2013 to July 2024, we analyze relationship of serum Lp-PLA2 levels with diffuse pulmonary emphysema and pulmonary functions. In univariate analysis, group differences were assessed with t-tests for numerical variables and Chi-square tests for categorical data. Variables found to be statistically significant (two-sided P < 0.05) in univariate analysis were subsequently included as covariates in multivariate analysis, performed using a binary logistic regression model. Odds ratios and 95% confidence intervals were calculated to assess the differences.

Results: We established 2 case-control populations: the Imaging population (1056 subjects, mean age 57.666 ± 8.700 years old, 89.9% male) selected from 24,670 initial records, and the Pulmonary Function population (279 subjects, mean age 52.082 ± 11.473 years old, 71.4% male) selected from 1868 initial records. Univariate analysis revealed that serum Lp-PLA2 levels were significantly higher in patients with diffuse pulmonary emphysema, obstructive ventilatory dysfunction as well as small airway dysfunction compared to those without (454.682 ± 141.382U/L vs. 423.330 ± 140.658U/L, P < 0.001; 475.059 ± 157.181U/L vs. 420.824 ± 142.119U/L, P = 0.006; 475.31 ± 148.980U/L vs. 439.036 ± 157.977U/L, P = 0.049, respectively). Multivariate analysis further showed higher Lp-PLA2 levels were associated with increased risks of diffuse pulmonary emphysema, obstructive ventilatory dysfunction as well as small airway dysfunction. Using Lp-PLA2 ≤ 300 U/L as reference, odds ratios for the aforementioned conditions showed a gradually increasing trend with every 100U/L increase in Lp-PLA2 levels.

Conclusions: Our preliminary study suggests that Lp-PLA2 is independently associated with diffuse pulmonary emphysema, obstructive ventilatory dysfunction as well as small airway dysfunction, which are commonly seen in COPD development. These findings indicated a possible association between Lp-PLA2 and COPD, though further validation is needed in a large cohort of COPD patients.