Absence of diabetes mellitus type 2 in obese children and adolescents in the north of Spain.

Background: The worldwide epidemic of childhood obesity has been accompanied by an increase in the incidence of carbohydrate metabolism disorders.

Objective: To determine the prevalence of type 2 diabetes mellitus (T2DM) and other carbohydrate metabolism disorders in obese young people in the Basque Country (Spain).

Design: Prospective observational study.

Patients: We studied 136 obese Caucasian children and adolescents (body mass index ≥2 SDS above the mean).

Measurements: Their severity of obesity was classified as mild <3 SDS or moderate-to-severe ≥3 SDS. Data were collected on clinical and metabolic parameters; insulin resistance (IR) was calculated using the homeostasis model assessment, and an oral glucose tolerance test (OGTT) was carried out.

Results: T2DM was not found. Impaired glucose tolerance (IGT) was found in 9.6% of patients being higher in moderate-to-severe obesity (12.8% vs. 2.4%; p=0.048) and in patients with acanthosis nigricans (27.8% vs. 6.8%; p=0.016). No differences were detected by sex or pubertal development in metabolic results as a function of OGTT's response. IR (13.5%) was higher among those with moderate-to-severe obesity, in patients with acanthosis nigricans and was associated with other cardiovascular disease risk factors.

Conclusions: We found no children with T2DM. The prevalence of IGT and IR was related to severity of obesity, to the association of acanthosis nigricans and was associated with cardiovascular risk.