Abstract
BACKGROUND: In this study, we aimed to evaluate the relationship between the body mass index (BMI) of participants in their 20s (20s_BMI) and the risk of developing various chronic metabolic diseases when they were over the age of 65 years. We also investigated how quickly these values worsened after 65 years of age. METHODS: This 8-year prospective cohort study targeted elderly people aged 65 years or older with three healthcare visits at 3-4 to year intervals. Participants were divided into four groups according to their 20s_BMI and the occurrence and changes in body weight and fatty liver were observed for approximately 8 years. RESULTS: A total of 1,130 people aged 65 years or older were included. In the 65-69 years age group, as the 20s_BMI increased, weight, BMI, waist circumference, and hip circumference all significantly increased (all P < 0.001); furthermore, the incidence of metabolic syndrome also significantly increased (P < 0.05). In particular, the rates of deterioration in weight, BMI, waist circumference, and waist-to-hip ratio were high in people aged 75 years and older (all P < 0.001). The Framingham Steatosis Index and Hepatic Steatosis Index tended to increase as the 20s_BMI increased; moreover, they all showed a worsening trend toward the second and third visit. CONCLUSION: We found that a high 20s_BMI continued to be high even after the age of 65 years and had a negative impact on the occurrence and worsening of metabolic dysfunction-associated steatotic liver disease. This suggests that weight management starting in the 20s is important to prevent the progression of chronic diseases after the age of 65 years.