Abstract
The prevalence of young-onset (diagnosis at age < 40 years) type 2 diabetes mellitus (T2DM) is increasing globally. Young-onset T2DM has a common pathophysiology of glucose dysregulation as in late-onset T2DM. However, it presents a greater association with obesity and a more rapid decline in β-cell function than late-onset T2DM. Accumulating evidence indicates that disease progression in young-onset T2DM is rapid, resulting in early and frequent development of microvascular and macrovascular complications, as well as premature death. Improper management and low adherence to medical therapy are important issues in young-onset T2DM. This review discusses the epidemiology, disease entity, and clinical issues associated with young-onset T2DM. We also present the prevalence and clinical characteristics of patients with young-onset T2DM in South Korea.