Prevalence of type 2 diabetes in children in Birmingham

EDITOR—In their editorial on type 2 diabetes in children Fagot-Campagna et al have described the American experience of this emerging condition.1 We represent the Paediatric Diabetes Subgroup of the Pan-Birmingham Diabetes Advisory Group and wish to describe our experience of type 2 diabetes in children in Birmingham.

We are responsible for 506 children with diabetes mellitus in Birmingham Health Authority; together our hospitals serve a paediatric population of 261 811.2 The first case of childhood type 2 diabetes in Birmingham was diagnosed in 1993, and since then we have seen 17 children with the disease, of whom 10 remain in the paediatric clinics. Of these 17 children, 15 are female and 15 are South Asian. Three have type 2 diabetes after bone marrow transplantation.

In the 12 months to December 2000, 67 children presented with diabetes, of whom four were new presentations of type 2 diabetes. From this we can estimate that in our population the crude prevalence of type 2 diabetes in those aged under 18 is 0.038 per 1000, with an annual incidence of 1.52 per 100 000. This compares with a crude prevalence of type 1 diabetes in our population of 1.818 per 1000 and an incidence of 23.30 per 100 000.

We recently reported on eight British children aged 9–16 with type 2 diabetes, who were all female and overweight with a family history of diabetes.3 In contrast to the American experience of this condition in Native American, black, and Hispanic children,4 these children were all of South Asian or Arab origin. The condition presented insidiously without ketosis, and most of the children were asymptomatic at the time of diagnosis. All had features of insulin resistance (acanthosis nigricans or high plasma insulin or C peptide concentrations), and the high frequency of associated hypertension, dyslipidaemia, and features of polycystic ovarian syndrome in this cohort suggests underlying metabolic syndrome.5

Whether the emergence of type 2 diabetes in children from ethnic minorities has implications for the wider paediatric population is unclear, as is the part that obesity may play in its development. Not all of our children with type 2 diabetes are overweight, and this is clearly a heterogeneous condition in children. A national survey is under way under the auspices of the British Society of Paediatric Endocrinology and Diabetes to ascertain how many children are affected in the United Kingdom.