The Relationship of Glycemic Control, Insulin Dose, and Race with Hypoglycemia in Youth with Type 1 Diabetes

IntroductionBlack youth with T1D have been reported to experience more episodes of hypoglycemia than white patients, despite blacks having higher levels of HbA1c. We hypothesized that black patients may be prescribed higher daily doses of insulin putting them at greater higher risk for hypoglycemia.MethodsWe performed a retrospective analysis of data from a study of social and environmental factors influencing HbA1c in a biracial pediatric population with T1DM. Changes in patient insulin dose were made at clinic visit based on their self-monitored glucose (SMG) data. Insulin dose (units/kg/d) was compared with HbA1c, reported hypoglycemic episodes and occurrence of low blood glucose from SMG data.ResultsAge, duration of diabetes and BMI-z were similar for black and white patients. Black patients had higher levels of HbA1c and mean blood glucose (MBG). HbA1c was higher in blacks even after adjustment for MBG. Reported insulin dose increased with increasing HbA1c (ρ = 0.30, p = 0.0052) or MBG (ρ = 0.36, p < 0.0008). There was no difference in insulin dose between blacks and whites. Reported hypoglycemia was inversely associated with HbA1c and MBG, but there was no racial difference. Occurrence of low glucoses from meter data was slightly higher in whites (p = 0.047).ConclusionInsulin dose increased with increasing HbA1c or MBG for both groups. Occurrence of hypoglycemia was inversely related to glycemic control. There was slightly higher occurrence low glucose meter readings in white patients. Reported racial disparities in occurrence of hypoglycemia and insulin dosing may be due to clinic specific factors.