Lean diabetes: 20-year trends in its prevalence and clinical features among Korean adults.

Background: We investigated the prevalence and clinical characteristics of type 2 diabetes mellitus in lean Korean adults. Methods: We analyzed data from the Korea National Health and Nutrition Examination Survey 2001–2021 among adults aged ≥ 19 years. Trend analyses between 2001 and 2019–2021 (n = 89,720) and comparative analyses of multiple clinical characteristics between patients with type 2 diabetes with and without overweight/obesity were conducted (n = 2,284). Results: Between 2001 and 2019–2021, the estimated prevalence of lean type 2 diabetes (body mass index [BMI] < 23 kg/m²) increased from 6.6 to 8.8%, representing a 33.3% increase. This was a similar extent of increase of type 2 diabetes associated with being overweight or obese (12.1–16.3%, + 34.7%). The increase in the prevalence of lean type 2 diabetes was more pronounced among females, while the increase among those who were overweight or obese was more pronounced among males than their counterparts. Although the overweight/obese type 2 diabetes group (T2DM group) showed more risk factors for cardiovascular disease, the lean T2DM group had lower insulin levels and reduced muscle mass and strength. Conclusions: The prevalence of lean type 2 diabetes among Korean adults is increasing, at a rate similar to type 2 diabetes in overweight/obese individuals. Patients with lean type 2 diabetes showed decreased beta-cell function and sarcopenia. These findings emphasize the need for tailored management strategies for lean type 2 diabetes given its characteristics and rising prevalence. [ABSTRACT FROM AUTHOR]