Serum Alanine Aminotransferase Levels as a Marker of Predicting Chronic Obstructive Pulmonary Disease Development: A Large-Scale Retrospective Cohort Study in Korean Populations

Background: While early detection and prediction of chronic obstructive pulmonary disease (COPD) are important to improve COPD prognosis and outcomes, no serologic marker has been identified to predict COPD development. Alanine aminotransferase (ALT) can reflect skeletal muscle volume and indirectly reflect general performance scales significantly associated with COPD development and prognosis. We investigated the ability of ALT levels to predict COPD development using a population-based cohort database. Methods: We used the health check-up cohort database of the Korean National Health Interview Survey from 2002 to 2003 after excluding subjects with COPD or liver disease, and assessed COPD development for 13 years according to ALT levels at baseline (group 1, ALT [IU/L] <10; group 2, 10≤ALT<20; group 3, 20≤ALT<30; group 4, 30≤ALT<40; group 5, ALT≥40). Findings: Among 422,452 subjects, group 1 were predominantly females and never or ex-smokers compared to group 5. In males or current smokers, COPD development was most prevalent in group 1, and incidence decreased as group number increased (males: 4·2%, 4·2%, 3·9%, 3·5%, and 2·9%, respectively, P<0·0001; current smokers: 5·4%, 5·0%, 4·5%, 3·9%, and 3·3%, respectively, P<0·0001). Following Cox regression analysis for males or current smokers, group 5 was more preventative in COPD development than group 1 (males: HR, 0·807, P=0·0384; current smokers: HR, 0·741, P=0·0181). However, the ability of ALT levels to predict COPD development was weak in females and never or ex-smokers. Interpretation: We suggest that males or smokers who present with low ALT levels should be carefully monitored for COPD development. Funding Statement: The authors stated: "None." Declaration of Interests: None of the authors have any conflicts of interest to declare. Ethics Approval Statement: The study was approved by the Institutional Review Board of Gangnam Severance Hospital (number: 3-2019-0123). The requirement for informed consent was waived considering the retrospective nature of this study.