Risk of complications in adulthood following childhood metabolic dysfunction-associated steatohepatitis based on Korean national health insurance data

The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD), which can be complicated by metabolic dysfunction-associated steatohepatitis (MASH), is increasing worldwide. This study aimed to determine the risk of complications occurring in adulthood due to childhood MASH. This matched cohort study enrolled 12,894 children and adolescents aged between 7 and 18 years registered with the Korean National Health Insurance Service Database for the period 2002–2021. MASH was defined by the diagnostic code K75.8 before 19 years of age. The control group enrolled patients without MASH. The MASH and non-MASH population were matched 1:5. Among 12,894 MASH patients and 921,141 non-MASH patients, we analyzed the frequency of complications for 1–10 years, starting from 19 years of age, and medical costs, The MASH group had a higher hazard ratio of complications than the non-MASH group in adulthood, including liver fibrosis and cirrhosis, hypertensive disease, hyperlipidemia, diabetes, cancer, and mental illness. In addition, patients in the MASH group had higher medical costs than patients in the non-MASH group for other diseases, including for cerebrovascular and liver fibrosis. Children with MASH are at an increased risk of various complications in adulthood, inflicting a significant medical burden, necessitating more active management and intervention.