Obesity at the onset of diabetes in an ethnically diverse population of children: what does it mean for epidemiologists and clinicians?

Abstract

It is often difficult to determine the pathophysiology of childhood diabetes at onset, particularly in overweight children, because obesity has been associated with both type 1 and type 2 diabetes. We compared children at the diagnosis of diabetes in a multiethnic population-based registry to understand the epidemiology of the disease during a time of rapidly changing diagnostic and treatment norms. Incident diabetes was ascertained in Chicagoans who were aged 0 to 17 years from 1985 to 2001. We classified as type 2 those with polycystic ovary syndrome, acanthosis, or a physician's note indicating type 2 or those who reported subsequent use of oral agents (n = 203); 73% of them were also obese. Patients with obesity at onset but no other indicator of possible type 2 (n = 197) were classified as having obesity-related/undetermined type. The remaining 842 cases were classified as type 1. Logistic regression analyses were conducted. Fully 32% of cases were classified as non-type 1, including 37% of non-Hispanic blacks, 30% of Latinos, and 14% of non-Hispanic whites. The proportion of obesity-undetermined and type 2 increased over the 17 years. Comparing the 3 patient groups, type 2 cases were more often female, non-Hispanic black, and older and had a first-degree diabetic relative, whereas Latino boys were overrepresented among the obese/undetermined. Obesity is prevalent in youths with newly diagnosed diabetes, particularly during recent years. The growth in non-type 1 diabetes in children since 1985 likely reflects both a true increase and greater physician awareness of the possibility that type 2 diabetes may occur in children.