Type 2 diabetes in children and adolescents: key considerations based on the 2025 Korea Diabetes Association clinical practice guidelines for diabetes management

Jieun Lee; Sung Eun Kim; Yong Hee Hong

doi:10.6065/apem.2550270.135

To the editor,

The prevalence of type 2 diabetes mellitus (T2DM) among Korean youths has increased significantly, reflecting global trends. According to national database reports, T2DM prevalence among Korean children, adolescents, and young adults increased from 2.27 per 10,000 in 2002 to 10.08 per 10,000 in 2016—a 4.43-fold increase over 15 years [1]. This increase is closely linked to the pediatric obesity epidemic in Korea and demographic factors such as increases in maternal age and small for gestational age births, both established independent risk factors for youth-onset T2DM [1]. Youth-onset T2DM is associated with increased risk of cardiovascular complications compared with adult-onset cases, emphasizing the critical need for early screening and effective management [2].

In response, the Korean Diabetes Association (KDA) published updated pediatric guidelines in 2025 [3]. The chapter on management of T2DM in children and adolescents aligns closely with the latest international standards, integrating key recommendations from the 2025 Standards of Care in Diabetes of the American Diabetes Association and the 2024 Clinical Practice Consensus Guidelines of the International Society for Pediatric and Adolescent Diabetes [4,5]. That chapter comprises 7 key components: screening, lifestyle modification, glycemic goal, pharmacologic treatments, treatments for obesity, evaluation of complications, and transition to adult care clinics (Fig. 1).

1. Screening

Screening for T2DM is recommended in children and adolescents aged ≥10 years or at puberty onset who are overweight/obesity (body mass index [BMI]≥85th percentile). Fasting plasma glucose, 2-hour plasma glucose, or glycated hemoglobin (HbA1c) can be used for screening, and the test should be repeated at least every 3 years in the situation of increased BMI. Given the rising prevalence of T2DM even among youth without obesity, early screening and careful differentiation from type 1 diabetes are necessary, despite limited evidence for universal screening [6].

2. Lifestyle modification and education

Immediate initiation of intensive lifestyle modification and structured diabetes education by a multidisciplinary team is essential upon diagnosis of T2DM. Active participation of family members and caregivers significantly improves adherence and clinical outcomes. Lifestyle interventions focusing on dietary changes, regular physical activity, and weight reduction have demonstrated effectiveness in delaying diabetes progression and minimizing complications, with minimal associated risks [7].

3. Glycemic goal

The recommended HbA1c target for pediatric T2DM is <6.5%, based on expert consensus and extrapolated evidence from relevant populations [4,5]. This stringent glycemic target accounts for the lower risk of hypoglycemia and the substantially higher long-term risk of diabetes-related complications among youth. HbA1c levels should be evaluated every 3 months to ensure optimal glycemic control.

4. Pharmacologic treatments

Initial pharmacologic treatment for children and adolescents with T2DM should be based on glycemic status. Metformin monotherapy is recommended as first-line therapy for stable patients with HbA1c <8.5%. Insulin therapy, alone or combined with metformin, should be initiated in patients presenting with ketosis or HbA1c ≥8.5%. If glycemic targets remain unmet with metformin alone, basal insulin should be added. Further intensification to multiple daily injections or insulin pump therapy may be necessary. Newer medications such as glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter-2 inhibitors are not yet approved for pediatric diabetes in Korea [8].

5. Treatments for obesity

Adolescents aged ≥12 years with T2DM and class 2 obesity (BMI ≥120% of the 95th percentile) may be treated with liraglutide, supported by evidence showing reductions in HbA1c, body weight, and fasting glucose [9]. Bariatric surgery may also be considered after completion of linear growth in adolescents with severely uncontrolled diabetes or obesity-related comorbidities. While bariatric surgery achieves substantial improvements in glycemic control and weight loss, associated risks including nutritional deficiencies and surgical complications necessitate careful individualized benefit-risk assessments [10].

6. Evaluation of complications

Regular screening for diabetes-related comorbidities and microvascular complications is critical, given their increased prevalence and severity in youth-onset T2DM [2]. Annual evaluation for nephropathy, retinopathy, neuropathy, hypertension, dyslipidemia, and liver dysfunction is strongly recommended. Additionally, routine mental health screening for depression, anxiety, and psychological stress is necessary, as these conditions negatively impact diabetes management outcomes and quality of life.

7. Transition to adult care clinics

Structured transition planning to adult diabetes care should begin at least 1 year prior to transfer. A well-coordinated transition process minimizes interruptions in medical care, maintains glycemic control, and reduces long-term diabetes-related complications.

In summary, the 2025 KDA pediatric diabetes guidelines provide comprehensive and evidence-based recommendations consistent with current international standards. These guidelines represent a significant advancement in pediatric T2DM management in Korea, serving as a practical clinical resource. Regular updates to reflect evolving clinical evidence and domestic healthcare needs are anticipated.

Notes

Conflicts of interest

No potential conflict of interest relevant to this article was reported.

Funding

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Acknowledgments

We thank the KDA for its support. We are also grateful to Professor Byung-Wan Lee and Professor Shinae Kang (Department of Internal Medicine, Yonsei University College of Medicine) and to Professor Jaehyun Kim (Department of Pediatrics, Seoul National University Bundang Hospital) for their valuable guidance and insightful comments during the preparation of this editorial.

Fig. 1.

Management of T2DM in children and adolescents. Screening, lifestyle modification/education, pharmacologic treatment, and options for obesity treatment are presented sequentially. T2DM, type 2 diabetes mellitus; BMI, body mass index; HbA1c, glycated hemoglobin.

References

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