Triglyceride-glucose index and preserved ratio impaired spirometry in 89,809 individuals without self-reported overt clinical disease.

Introduction: While both preserved ratio impaired spirometry (PRISm) and triglyceride glucose index (TyG) are established risk factors for cardiometabolic diseases, the metabolic characteristics and prevalence of PRISm differ by ethnic group. However, this association has not been directly examined in Asian populations. Therefore, we aimed to investigate whether TyG is associated with PRISm in a large Korean population without self-reported overt clinical disease. Methods: In this cross-sectional study, 89,809 adults (46,739 men; mean age: 38.5 years) with health examinations in 2019 were divided into quartiles according to their TyG. Lung function phenotypes were evaluated using fixed cut-offs and lower limit of normal (LLN) criteria, with LLN defined as the 5th percentile of our study population. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for PRISm were estimated and compared to the lowest TyG quartile (reference) group. Results: The mean TyG was 8.34 ± 0.57, and the prevalence of PRISm was 3.4%, showing a significant increase across TyG quartiles ( Discussion: In conclusion, higher TyG quartiles were associated with PRISm in middle-aged Koreans without self-reported overt clinical disease, suggesting the potential link between metabolic status and PRISm risk. However, longitudinal studies are required to confirm these findings.