What is the incidence of diabetes (we do not know which type) in a six-year-old child with Down’s syndrome and congenital cardiomyopathy (patent A-V for which surgery has already been performed to close it)?

According to information from the Centers for Disease Control (CDC), the incidence of type 1 diabetes in children ages 0 to 19 in the U.S. is about one case for every 500 children! So, it is very common AND for reasons not well understood, the incidence seems to be increasing. Certain populations have higher incidences of type 1 or type 2 diabetes. In a six-year-old, type 1 would be more likely. Type 1 diabetes is very often associated with an autoimmune destruction of the pancreas’ ability to produce insulin. If your child has Down’s Syndrome, then you probably have learned that individuals with Down’s Syndrome have higher rates of autoimmune diseases (type 1 diabetes, thyroid diseases, celiac disease and others) as well as leukemia.

As you probably know, the incidence of Down’s Syndrome is also dependent on several factors, especially age of the mother. For instance, for women over age 40 years at the time of pregnancy, the risk of Down’s Syndrome may be 1 case per 110. For women age 35 to 40, the risk may be 1 case per 400 pregnancies. Overall, for ALL births, the incidence of Down’s Syndrome has been estimated to be about 1 case per 800 births, so also fairly common.

My understanding is that congenital heart disease is very common in children with Down’s Syndrome, approaching 50% of cases. Furthermore, I found a source that indicated that 45% of these congenital heart disease cases involves some defect in the AV canal.

So, the short answer to your question as to what is the incidence of diabetes (probably type 1) in the child you describe is “relatively high” at least when compared to the general population.

DS