Results from the Diabetes Control and Complications Trial (DCCT), a prospective randomized controlled study, suggest that glycosylated hemoglobin control below 7% may reduce the incidence of microvascular complications in patients with type 1 diabetes.
The ADA emphasizes that glycemic control goals should be individualized to minimize the risk of severe hyperglycemia and hypoglycemia. Glycemic control goals should be set based on the patient’s duration of diabetes, age, life expectancy, co-morbidities and complications.
Glycemic control goals for children The glycosylated hemoglobin control goal for pediatric patients aged 13-19 years in DCCT is 7.5%, and for adult patients with type 1 diabetes is 7%.
The ADA’s traditional recommendations for glycemic control goals in children are glycosylated hemoglobin less than 8.5% under age 6, glycosylated hemoglobin less than 8% between ages 6-12, and glycosylated hemoglobin less than 7.5% between ages 13-19, as close to normal blood glucose and glycosylated hemoglobin levels as possible if conditions permit, but with the risk of severe hypoglycemia avoided or minimized.
The ADA decided to change the goal of glycemic control in pediatric patients with type 1 diabetes, considering the mixed evidence of the adverse effects of hypoglycemia on brain development in the past and the increasing number of studies showing a significant increase in the potential risk of hyperglycemia and glucose changes on the central nervous system. The International Society for Child and Adolescent Diabetes (ISPAD) recommends an A1C target of 7.5% for all patients in the pediatric phase. The ADA also advocates an A1C goal of 7.5% for all pediatric patients.
Adult Glycemic Control Goals The occurrence of complications and comorbidities in adult patients with type 1 diabetes is individually variable and, therefore, glycemic control goals vary. For non-pregnant adult patients with type 1 diabetes, a reasonable glycated hemoglobin control goal is 7%. For individual patients with short duration of diabetes, long life expectancy, no obvious cardiovascular disease, no obvious hypoglycemia or other adverse reactions, the glycosylated hemoglobin control target can be less than 6.5%. For patients who are old and frail, have severe hypoglycemia, have limited life expectancy, or have microvascular or macrovascular complications, the treatment goal may be relaxed to 8.5%. In patients of any age with type 1 diabetes, glycemic control should be based on self-monitoring of blood glucose (SMBG) levels or ambulatory glucose monitoring (CGM) data in addition to glycosylated hemoglobin to adjust treatment regimens.