12-year Trends in Lipid Levels in Korean Children and Adolescents: A Cross-sectional Study Based on the Korea National Health and Nutrition Examination Survey

Background: Dyslipidaemia at a young age is one of the risk factors of adulthood cardiovascular disease. However, investigations on the trends in lipid levels among the youth are scarce. Thus, we aimed to analyse the trends in lipid levels in Korean youth from 2007 through 2018. Methods: This cross-sectional study investigated the lipid profiles of 10,734 youths aged 10-18 years using data from the four phases of the Korea National Health and Nutritional Examination Survey: IV (2007-2009), V (2020-2012), VI (2013-2015), and VII (2016-2018). We assessed the age-, sex-, and body mass index (BMI)-adjusted mean levels of lipids at each survey. Findings: The mean levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol (non-HDL-C) levels increased from phase IV to VII. Among boys, the prevalence of subjects with acceptable levels of TC, LDL-C, and non-HDL-C decreased, whereas that of subjects with adverse levels increased from phase VI to VII. In BMI- and sex-specific analysis, adverse trends in TC, LDL-C, and non-HDL were more apparent among boys with normal BMI than among those who were overweight and obese. Among girls, the mean TC, LDL-C, and triglycerides levels increased in subjects with normal BMI and overweight. Interpretation: Our results suggest worsening trends in lipid levels and dyslipidaemia among Korean youth. These adverse trends were seen even in youth with normal BMI. These findings indicate the need for more concern about lipid levels in youth with normal BMI as well as those with overweight and obesity.