Gastrointestinal CancerAssociation of weight change in young adulthood with subsequent risk of hepatocellular carcinoma: a national cohort studyKim, Kyuwoonga; Choi, Seulggiea; Lee, Gyeongsilb; Son, Joung Sikb; Kim, Kyae Hyungb,,c; Park, Sang Mina,,b,,dAuthor Information aDepartment of Biomedical Sciences, Seoul National University Graduate School bDepartment of Clinical Medical Sciences, Seoul National University, College of Medicine cInstitute for Public Health and Medical Services, Seoul National University dDepartment of Family Medicine, Seoul National University Hospital, Seoul, Republic of Korea Received 5 March 2020 Accepted 29 May 2020 Correspondence to Sang Min Park, MD, MPH, PhD, Department of Family Medicine and Biomedical Sciences, College of Medicine, Seoul National University, 101 Daehak-ro, Jongno-gu, Seoul 03080, Republic of Korea, Tel: +82 2 2072 3331; fax: +82 2 766 3276; e-mail: [email protected] European Journal of Cancer Prevention: May 2021 - Volume 30 - Issue 3 - p 211-219 doi: 10.1097/CEJ.0000000000000610 Buy Metrics Abstract Risk of hepatocellular carcinoma (HCC) in young adults might be clinically overlooked for future HCC risk. Thus, we examined the association between weight change and future risk of developing HCC in young adults. We collected a nationwide and population-based cohort data of more than 2.2 million men and women aged between 20 and 39 who were without previous cancer diagnosis and underwent two consecutive biennial national health screening between 2002 and 2005 from the National Health Insurance Service database. The individuals were categorized as weight loss (≥5.0 kg and 2.0–4.9 kg), stable weight (weight gain or loss <2.0 kg), and weight gain (2.0–4.9 kg and ≥5.0 kg) and were followed-up for incident HCC from 1 January 2006 to 31 December 2018. During 12 years of follow-up, there were 2694 HCCs in men and 306 HCCs in women. In the multivariable Cox proportional hazards model adjusted for socioeconomic, health behavior, medical characteristics, and family history, weight gain of more than 5.0 kg and between 2.0 and 4.9 kg were associated with significantly increased risk in young men [hazard ratio (HR) 1.16, 95% confidence intervals (95% CI) 1.01–1.32] and young women (HR 1.34, 95% CI 1.01–1.77), respectively. Protective association of weight loss with HCC was not observed. The association of weight gain and HCC risk was stronger in young adults with underlying liver diseases compared to those without any liver disease (Pheterogeneity < 0.001). Weight gain during young adulthood should not be clinically overlooked for future HCC risk, especially among those with underlying liver diseases. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.