Association between steatotic liver disease (MASLD, met-ALD, and ALD) with preserved ratio impaired spirometry: a population-based study.

BACKGROUND: Preserved Ratio Impaired Spirometry (PRISm) is related to increased morbidity and mortality. Recently, metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction-associated alcohol-related liver disease (Met-ALD), and alcohol-associated liver disease (ALD) have been recognized as systemic metabolic disorders. The association between these novel liver disease categories and PRISm remains unclear. METHODS: We analyzed data from 23,414 adults aged ≥ 40 years from the 2010–2019 Korean National Health and Nutrition Examination Survey. Participants with obstructive lung patterns were excluded. MASLD, Met-ALD, and ALD were defined based on hepatic steatosis index, cardiometabolic criteria, and alcohol consumption. PRISm was defined as FEV₁/FVC ≥ 0.7 and FEV₁ <80% predicted. Complex sample logistic regression was used to examine associations, adjusting for sociodemographic, behavioral, and clinical variables. Subgroup analyses by sex and sensitivity analyses using AST-to-platelet index (APRI) for advanced fibrosis and lower limit of normal (LLN)-based criteria for PRISm were performed. RESULTS: Among the study population, 3,182 had PRISm. MASLD, Met-ALD, and ALD were more prevalent in the PRISm group than in the normal spirometry group. In fully adjusted models, MASLD (OR 1.36; 95% CI, 1.19–1.55) and Met-ALD (OR 1.51; 95% CI, 1.14–2.01), and ALD (OR 2.38; 95% CI, 1.65–3.41) were associated with increased odds of PRISm. These associations were significant in males but not in females. Sensitivity analyses using LLN showed consistent results. Participants with advanced fibrosis (APRI ≥ 0.34) also had higher odds of PRISm in both sexes. CONCLUSION: MASLD, Met-ALD, and ALD are associated with PRISm, particularly in men, suggesting a possible link between liver-based metabolic dysfunction and non-obstructive pulmonary impairment. These findings highlight the need for integrated approaches to managing metabolic liver disease and lung function decline.