Our four year old daughter was diagnosed with type 1 diabetes about five months ago, and we have had trouble, for brief periods, controlling her blood glucose but always manage to regain control in less than a week. At worst case she runs 200-300 mg/dl [11.1-16.7 mmol/L] for three to four days in a row. How significant is this to her long term health?

Having a brief run of higher glucoses likely has little, if any, long term health effects. Indeed, the higher glucose readings may indicated an important short-term issue, being the heralding of DKA [diabetic ketoacidosis] which can be very serious or even fatal. That is why many centers suggest to families that when the blood glucose of a child with type 1 diabetes is greater than 240 mg/dl [13.3mmol/L] (especially two readings about fours hours apart), or during illness (particularly one with vomiting), that ketones be checked for either in the urine or in the blood!

There are some studies in adults suggesting that higher glucose readings right after meals may be an issue, even if the other, pre-meal glucose readings and/or the hemoglobin A1c values are acceptable. This has not been studied well in children.

DS
Additional comments from Dr. John Schulga:

It sounds like you are doing really well with your child. It is felt that short periods of high readings are not detrimental to long term complications. It is the overall control that is important.

JS