Ask the Investigators – Dr. Rochelle Naylor

RochelleDr. Naylor is our expert on MODY (Maturity-Onset Diabetes of the Young). Today she answers some of the most common questions we receive about GCK-MODY (MODY2).

Do people with GCK-MODY need any type of treatment for this condition?

Most individuals with GCK-MODY will not need any type of blood sugar-lowering treatment (insulin, oral medications, special diets, such as low carbohydrates). Studies such as the one here suggest that putting individuals with GCK-MODY on insulin or other diabetes medications does not change their HbA1c value. Because treatment has no appreciable impact on glycemic control in the majority of GCK-MODY, generally treatment is not recommended.

However, there are exceptions. Women who are pregnant may need to take insulin if the fetus does NOT carry the GCK mutation. If the fetus does carry the mutation, the mildly elevated blood sugars will be “normal” to the baby, just as they are to the mother. Insulin resistance can develop in people with GCK due to being overweight (as occurs with type 2 diabetes) – these individuals may benefit from some type of treatment for their insulin resistance. We have even seen the rare circumstance where GCK-MODY and autoimmune type 1 diabetes exist in the same person; in a case like this, insulin would be required.

What are the risks of developing complications (eye disease, heart disease, kidney disease) for people with GCK-MODY?

Individuals with GCK-MODY do not appear to be at the same level of risk for developing diabetes-related complications such as eye disease, heart disease, and kidney disease as compared to individuals with type 1 and type 2 diabetes. In fact, this study compared three groups of people – those with GCK-MODY, family members unaffected by GCK-MODY, and individuals with type 2 diabetes. Those with GCK-MODY had a risk of developing complications that was similar to their family members unaffected by GCK-MODY and less than those with type 2 diabetes. A larger portion of GCK-MODY patients had a small amount of abnormalities in their eye exams as compared to their unaffected family members, but it was not significant enough to need any type of eye laser therapy.

This study suggests that having mildly high blood sugars, as occurs in GCK-MODY, does not commonly result in typical complications associated with diabetes.