Objective To analyze the distribution differences of lipid-related metabolic indicators between interstitial lung abnormality (ILA) and non-ILA, as well as between ILA subtypes, and to evaluate their associations with ILA and subpleural fibrotic ILA subtype which carries a high risk of progression. Methods A cross-sectional study was conducted based on a health screening cohort from West China Hospital of Sichuan University and four physical examination centers between January 2013 and January 2023. Propensity score matching was employed to balance baseline characteristics between ILA and non-ILA populations. Multivariate logistic regression, restricted cubic spline, and stratified interaction analyses were performed to assess the associations of triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), TG/HDL-C ratio, and the triglyceride-glucose (TyG) index with ILA and subpleural fibrotic ILA. Results Compared with the non-ILA group (n=6690), the ILA group (n=6690) exhibited higher levels of TG, LDL-C, TG/HDL-C ratio, and TyG index (P<0.05), and lower levels of TC and HDL-C (P<0.05). Compared with the non-fibrotic ILA group (n=5603), the fibrotic ILA group (n=1087) had lower levels of TG, TC, LDL-C, TG/HDL-C ratio, and TyG index (P<0.05). Elevated levels of TG [odds ratio (OR)=1.050, 95% confidence interval (CI) (1.023, 1.078), P<0.001], LDL-C [OR=1.067, 95%CI (1.021, 1.115), P=0.004], TG/HDL-C [OR=1.047, 95%CI (1.025, 1.069), P<0.001], and TyG [OR=1.106, 95%CI (1.039, 1.176), P=0.002] were independently associated with an increased odds of ILA, whereas higher TC [OR=0.954, 95%CI (0.919, 0.990), P=0.015] and HDL-C [OR=0.491, 95%CI (0.438, 0.549), P<0.001] were independent related to lower odds of ILA. Elevated HDL-C [OR=0.731, 95%CI (0.584, 0.909), P=0.005] showed an independent linear correlation with reduced odds of fibrotic ILA. Stratified analysis indicated that age (P-interaction=0.002) exerted a modulatory effect on HDL-C and fibrotic ILA. A risk prediction model of fibrotic ILA constructed using 8 indicators including age, HDL-C, and albumin yielded an area under the curve of 0.659 [95%CI (0.642, 0.677)]. Conclusions blood lipid profile and metabolic index exhibited heterogeneous distribution patterns across different subtypes of ILA. While elevated TG, LDL-C, TG/HDL-C, and TyG index, along with decreased TC and HDL-C, are independently associated with an increased risk of ILA, only HDL-C maintained a linear independent correlation with a reduced risk of fibrotic ILA. The predictive model integrating HDL-C, age and other indicators demonstrated moderate value for identifying fibrotic ILA. These findings highlighted the complex interplay between lipid metabolism and ILA and provide hematological evidence for the early identification of high-risk ILA subtypes.
Due to their diverse types, complex causes, high incidence, and difficult treatment, lung diseases have become major killers threatening human life and health, and some lung diseases have a significant impact on alveolar morphology and histology. Numerical simulation of alveolar mechanical response, alveolar flow field information, multiphase flow, and material transport based on computational fluid dynamics is of great significance for lung disease diagnosis, clinical treatment, and in vitro experiments. Starting from the simplification and pathological differences of geometric and mechanical models, this paper analyzes and summarizes the conditions and application scenarios of the airflow dynamics calculation method in pulmonary alveoli, to provide a reference for further simulation and application of the alveolar region.