My daughter has MODY and takes metformin HCL. She has concerns that she will become type 1. Is that possible? Our next appointment is not for a couple of months and I was hoping to calm her fears.

I am not doubting the diagnosis of MODY in your daughter. But, it is not very common and has strict criteria for diagnosis and the testing to confirm the diagnosis is extremely difficult. Indeed, there are six types of MODY described and only one (MODY-type 3) which is able to be confirmed with commercially available tests. In fact, MODY is described as being rather easily controlled with oral agents and metformin is not one of them. So, how confident are you or is your pediatric endocrinologist that your daughter really has MODY?

Presuming the diagnosis of MODY is correct, the natural history is that she would not be expected to develop type 1 diabetes because that is a different entity. Maybe what she is REALLY asking is, what are the chances she will require to take insulin to control her glucose levels? Remember, the act of taking insulin does not equal type 1. Many people with type 2 diabetes must still receive insulin. In other words, all type 1s require insulin; not all who take insulin are type 1s. If she cannot control her glucose levels with diet and exercise and proper oral medications, she may still warrant being treated with insulin injections.

DS