Down's syndrome in diabetic patients aged <20 years: an analysis of metabolic status, glycaemic control and autoimmunity in comparison with type 1 diabetes.

AIMS/HYPOTHESIS: Intellectual impairment in individuals with Down's syndrome and diabetes mellitus potentially limits the quality of diabetic control. In addition, these patients are at risk of having immunological abnormalities. The present study compared metabolic status and concomitant diseases in young (<20 years old) Down's syndrome patients with diabetes vs young type 1 diabetic patients.

METHODS

The Diabetes-Patienten-Verlaufsdaten is a longitudinal follow-up database, which collects data from 298 German and Austrian diabetes centres. Data available on diabetic patients aged <20 years were analysed statistically.

RESULTS

We compared data for 159 Down's syndrome patients with diabetes and 41,983 type 1 diabetic patients. The former used less insulin, but showed better glycaemic control (HbA1c). Diabetes onset during the first 3 years of life occurred in 18.9% of Down's syndrome patients with diabetes and in 6.4% of type 1 diabetic patients. Antibody titres indicative of coeliac disease and thyroid peroxidase antibodies were more frequent in Down's syndrome patients with diabetes. No significant differences were found regarding the beta cell autoantibodies studied.

CONCLUSIONS/INTERPRETATION: The age-of-onset distribution showed a shift towards younger ages and was bimodal in the Down's syndrome group. The better metabolic control found, despite intellectual impairment, in young Down's syndrome patients with diabetes cannot be conclusively explained by our data, but is likely to be due to a less complex lifestyle. Our data provide further confirmation that coeliac and thyroid antibodies are more prevalent in Down's syndrome. The presence of beta cell autoantibodies supports an autoimmune cause of diabetes in some children with Down's syndrome.