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/m) 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.