Long-term trends of lipid concentrations and lipid control in South Korea, 2007 to 2023: A nationwide representative study

Long-term trend studies on lipid concentrations and lipid control among Korean adults up to 2023 are limited. Therefore, this study aimed to assess nationwide trends in lipid concentrations and lipid control, including subgroup disparities, over a 17-year period. We used nationally representative data from the Korea National Health and Nutrition Examination Survey from 2007 to 2023. Lipid control was defined as total cholesterol (TC) <200 mg/dL among lipid-lowering medication users. Primary outcomes were age-standardized blood concentrations of TC, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), and the proportion achieving lipid control. Survey-weighted linear regression was used to estimate mean differences in lipid concentrations with 95% confidence intervals (CIs), and survey-weighted logistic regression was applied to assess subgroup differences in lipid control. A total of 97,129 nonpregnant adults aged ≥20 years were included in the analyses (female, 56.69%). Age-standardized mean TC levels increased in the overall population, from 184.7 mg/dL (95% CI, 183.8-185.6) in 2007-2009 to 189.7 mg/dL (188.6-190.7) in 2022-2023 (mean difference, 5.0 mg/dL [3.6-6.3]). In contrast, HDL-C improved, LDL-C declined, and TG levels showed no significant change. Among lipid-lowering medication users, mean TC decreased from 164.1 mg/dL (95% CI, 161.3-167.0) in 2007-2009 to 152.2 mg/dL (150.8-153.6) in 2022-2023, and lipid control rates increased from 72.97% (67.99-77.95) to 88.09% (86.33-89.85), respectively. However, several groups had significantly lower odds of lipid control: adults aged 20 to 44 years (weighted odds ratio, 0.39 [95% CI, 0.26-0.57]), individuals with high school education or less (0.82 [0.70-0.95]), and those with insufficient muscle strengthening exercise (0.75 [0.59-0.96]), compared with their respective reference groups. Lipid concentrations in Korean adults improved from 2007-2009 to 2022-2023, characterized by lower LDL-C, higher HDL-C, and stable TG levels. Lipid control among adults receiving lipid-lowering therapy also increased steadily over 17 years. However, disparities among younger adults and those with lower education underscore the need for targeted strategies to achieve more equitable improvements in lipid control.