Goh Eun Chung1, Eun Ju Cho2, Ji Won Yoon1, Jeong-Ju Yoo3, Young Chang4, Yuri Cho5, Sang-Hyun Park6, Kyungdo Han6, Dong Wook Shin7, Su Jong Yu8. 1. Department of Internal Medicine and Healthcare Research Institute, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Republic of Korea. 2. Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea. 3. Department of Gastroenterology and Hepatology, Soonchunhyang University Bucheon Hospital, Gyeonggi-do, Republic of Korea. 4. Department of Gastroenterology and Hepatology, Soonchunhyang University Seoul Hospital, Seoul, Republic of Korea. 5. Center for Liver and Pancreatobiliary Cancer, National Cancer Center, Goyang, Republic of Korea. 6. Department of Biostatistics, College of Medicine, Soongsil University, Seoul, Republic of Korea. 7. Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; Department of Clinical Research Design and Evaluation, Samsung Advanced Institute for Health Science, Republic of Korea; Supportive Care Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; Department of Digital Health, Samsung Advanced Institute for Health Science, Republic of Korea. Electronic address: dwshin.md@gmail.com. 8. Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea. Electronic address: sujongyu@gmail.com.
Abstract
BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of diabetes but has been rarely investigated in young adults. In this study, we investigated the relationship between NAFLD and incident diabetes risk in young adults using nationwide Korean population data. METHODS: This population-based cohort study from the Korean National Health Insurance Service included adults aged 20 through 39 years who underwent a health examination from 2009 to 2012. NAFLD was defined as a fatty liver index (FLI) ≥60 in the absence of alcohol consumption of ≥30 g/day. Newly diagnosed diabetes during follow-up was identified using claims data. Cox regression was used to calculate the hazard ratio for incident diabetes after adjusting for classical confounders. FINDINGS: Among the 5,254,786 participants, 9.3% had an FLI ≥60. During the median follow-up of 8.6 years, 91,885 cases of incident diabetes occurred. In multivariable analysis, the risk of incident diabetes was significantly higher in the NAFLD group than the control group (adjusted hazard ratio = 4.97, 95% confidence interval, 4.90-5.05). Stratified analyses showed higher associations in those who were ≥30 years, male, obese, smokers, alcohol consumers, and did not regularly exercise (all P < 0.001). CONCLUSIONS: NAFLD is associated with a five-fold increased risk of incident diabetes in young adults. These results suggest an independent high risk for incident diabetes in young adults and underscore the importance of paying early attention to patients who develop NAFLD before middle age.
BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of diabetes but has been rarely investigated in young adults. In this study, we investigated the relationship between NAFLD and incident diabetes risk in young adults using nationwide Korean population data. METHODS: This population-based cohort study from the Korean National Health Insurance Service included adults aged 20 through 39 years who underwent a health examination from 2009 to 2012. NAFLD was defined as a fatty liver index (FLI) ≥60 in the absence of alcohol consumption of ≥30 g/day. Newly diagnosed diabetes during follow-up was identified using claims data. Cox regression was used to calculate the hazard ratio for incident diabetes after adjusting for classical confounders. FINDINGS: Among the 5,254,786 participants, 9.3% had an FLI ≥60. During the median follow-up of 8.6 years, 91,885 cases of incident diabetes occurred. In multivariable analysis, the risk of incident diabetes was significantly higher in the NAFLD group than the control group (adjusted hazard ratio = 4.97, 95% confidence interval, 4.90-5.05). Stratified analyses showed higher associations in those who were ≥30 years, male, obese, smokers, alcohol consumers, and did not regularly exercise (all P < 0.001). CONCLUSIONS: NAFLD is associated with a five-fold increased risk of incident diabetes in young adults. These results suggest an independent high risk for incident diabetes in young adults and underscore the importance of paying early attention to patients who develop NAFLD before middle age.