Type 1 diabetes mellitus in early childhood: glycemic control and associated risk of hypoglycemic reactions.

OBJECTIVE

To assess the level of glycemic control and to determine whether more normal glycemic control, as measured by glycosylated hemoglobin, leads to frequent hypoglycemic episodes in young patients with type 1 diabetes mellitus.

MATERIAL AND METHODS

We undertook a retrospective review of the medical records of 59 children with type 1 diabetes diagnosed at age 9 years or younger, who underwent follow-up at our institution for at least 2 years. For each follow-up, insulin requirements, levels of glycosylated hemoglobin, and frequency of hypoglycemic reactions were analyzed for three age-groups--0 to 2 years, 2 to 5 years, and 5 to 9 years old.

RESULTS

The mean glycosylated hemoglobin for the first 2 years after diagnosis of type 1 diabetes was higher in children 0 to 2 years old in comparison with the other age-groups. This increased glycosylated hemoglobin occurred despite increased administration of insulin, expressed in units per kilogram daily, to these children (P < 0.05). Severe hypoglycemic reactions were more common in infants (55%) and children between 2 and 5 years old (45%) than in children from 5 to 9 years old (13%). In all age-groups, the mean glycosylated hemoglobin value closest to a hypoglycemic event and the mean glycosylated hemoglobin value for the 2-year study period were similar but were both less than 8% (the standard established by the Diabetes Control and Complications Trial). Most reactions had no clear cause in the youngest age-group, whereas a specific reason could usually be determined in children 2 to 5 years old.

CONCLUSION

Tight glycemic control is achievable in young patients with type 1 diabetes mellitus. Such tight control, however, may lead to an increase in the frequency of severe hypoglycemic reactions in this patient population. Our data support the guideline that children younger than 5 years should have a higher goal for premeal plasma glucose levels.