Diabetes Metab J.  2025 Mar;49(2):172-182. 10.4093/dmj.2024.0826.

Prevalence, Incidence, and Metabolic Characteristics of Young Adults with Type 2 Diabetes Mellitus in South Korea (2010–2020)

• Kim JY
• Lee J
• Moon JH
• Park SE
• Ko SH
• Choi SH
• Kim NH

• KMID: 2565342
• DOI: http://doi.org/10.4093/dmj.2024.0826

Abstract

Background
This study aimed to examine trends in the prevalence, incidence, metabolic characteristics, and management of type 2 diabetes mellitus (T2DM) among young adults in South Korea.
Methods
Young adults with T2DM were defined as individuals aged 19 to 39 years who met the diagnostic criteria for T2DM. Data from the Korean National Health Insurance Service-Customized Database (2010–2020, n=225,497–372,726) were analyzed to evaluate trends in T2DM prevalence, incidence, metabolic profiles, comorbidities, and antidiabetic drug prescription. Additional analyses were performed using the Korea National Health and Nutrition Examination Survey.
Results
The prevalence of T2DM in young adults significantly increased from 1.02% in 2010 to 2.02% in 2020 (P<0.001), corresponding to 372,726 patients in 2020. Over the same period, the incidence rate remained stable within the range of 0.36% to 0.45%. Prediabetes prevalence steadily increased from 15.53% to 20.92%, affecting 3.87 million individuals in 2020. The proportion of young adults with T2DM who were obese also increased, with 67.8% having a body mass index (BMI) ≥25 kg/m² and 31.6% having a BMI ≥30 kg/m² in 2020. The prevalence of hypertension, dyslipidemia, and fatty liver disease also increased, reaching 34.2%, 79.8%, and 78.9%, respectively, in 2020. Although the overall pharmacological treatment rate remained low, the prescription of antidiabetic medications with weight-reducing properties increased over the study period.
Conclusion
The prevalence of T2DM among young adults in South Korea nearly doubled over the past decade. The strong association with obesity and metabolic comorbidities emphasizes the urgent need for targeted prevention and management strategies tailored to this population.

Keyword

Diabetes mellitus, type 2; Disease management; Epidemiology; Obesity; Young adult

Figure

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  Fig. 1. Prevalence and incidence rate of type 2 diabetes mellitus (T2DM) in young adults (2010 to 2020). (A) Trends in number and prevalence rate of T2DM in young adults. (B) Trends in the prevalence rate of T2DM in young adults by sex. (C) Trends in the prevalence rate of T2DM in young adults by age group. (D) Trends in the incidence rate of T2DM in young adults.

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  Fig. 2. Prevalence rate and estimated number of prediabetes in young adults (2010 to 2020). M, million.

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  Fig. 3. Obesity in young adults with type 2 diabetes mellitus (T2DM). (A) Trends in mean body mass index (BMI) and waist circumference (WC) in young adults with T2DM. (B) Trends in mean BMI by sex. (C) Trends in the proportion of individuals with a BMI of ≥25, ≥30, ≥35, and ≥40 kg/m2 among young adults with T2DM. (D) Trends in the proportion of individuals with a BMI of ≥25 and ≥30 kg/m2 among young adults with T2DM, analyzed by sex.

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  Fig. 4. Trends in comorbidities and vascular complications in young adults with type 2 diabetes mellitus (2010 to 2020). (A) Prevalence of hypertension, dyslipidemia, and fatty liver disease. (B) Prevalence of vascular complications. MI, myocardial infarction; ESKD, end-stage kidney disease; PDR, proliferative diabetic retinopathy.

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  Fig. 5. Trends in antidiabetic medication use among young adults with type 2 diabetes mellitus. (A) Pharmacological treatment rate. (B) Prescription patterns for pharmacological treatments among those receiving antidiabetic medications. (C) Patterns of drug regimen combinations excluding insulin among those receiving antidiabetic medications. SU, sulfonylurea; TZD, thiazolidinedione; AGI, alpha-glucosidase inhibitor; DPP-4i, dipeptidyl peptidase-4 inhibitor; SGLT2i, sodium-glucose cotransporter-2 inhibitor; GLP-1RA, glucagon-like peptide-1 receptor agonist.

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