Which obese youth are at increased risk for type 2 diabetes? Latent class analysis and comparison with diabetic youth

Most obese youth screened for diabetes have normal fasting glucose levels. Identification of youth with increased risk for type 2 diabetes (T2D) is needed within this large population to guide further management.

Retrospective chart review was performed for obese youth, 8-20 yr old, who met American Diabetes Association criteria for screening (OB) or had T2D (D). Measures included body mass index z-score (BMIz) and homeostasis model assessment of insulin resistance (HOMA-IR) by fasting plasma glucose (FPG) and insulin. Statistics compared OB with D and further examined OB by latent class analysis (LCA).

Normal FPG was found in 91.5% of all obese youth (OBt n = 94) Comparison of OB with normal FPG (OBng; n = 86) and D (n = 44) was significant for family history of T2D (p = 0.008) without other associations. Evaluation of OBng by LCA showed three classes with increasing BMIz and HOMA-IR. Class 3 (32.5%; BMIz 2.66 ± 0.38; HOMA-IR 6.72 ± 2.29) differed from classes 1 and 2 (p < 0.05), and was associated with family history of T2D.

Currently recommended screening of obese youth by FPG is normal in 91.5%, but lacks further information to detect increased risk for youth-onset T2D. Evaluation of obese youth by LCA identified one third (class 3) in whom the combination of higher levels of BMIz, HOMA-IR, and family history suggests the greatest risk for T2D and targets them for further evaluation and intensive preventative management.