Mealtime insulin bolus adherence and glycemic control in adolescents on insulin pump therapy.

Poor self-management contributes to insufficient glycemic control in adolescents with type 1 diabetes (T1DM). We assessed the effects on glycemic control of adherence to self-measurement of blood glucose (SMBG) and insulin boluses in 90 adolescents with T1DM on insulin pump therapy over a 2-month period. We compared the number of insulin boluses and SMBGs around main meals to the "gold standard" of optimal diabetes management (SMBGs and a bolus before each main meal and SMBG before bedtime). The mean (95% CI) HbA1c levels were 2.9(1.7 to 4.0) mmol/mol lower for every additional insulin bolus and 3.1(1.6 to 4.5) mmol/mol lower for every additional SMBG. Patients performing SMBG and bolusing around each main meal had considerably lower HbA1c levels than those unable to do (95% CI for difference 4.3 to 10.4 mmol/mol and 11.5 to 20.1 mmol/mol respectively). For each additional mealtime bolus/day, the odds ratio of achieving target HbA1c levels of <58 mmol/mol was 6.73 (95% CI 2.94-15.38), after adjustment for gender, age, diabetes duration, and affective responses to SMBG in a multiple logistic regression model.Conclusion: Glycemic control in adolescents with T1DM on insulin pump therapy is strongly dependent on adherence to insulin boluses around mealtimes. What is Known: • In mixed groups of children and adolescents, insulin bolus frequency and self-monitoring of blood glucose (SMBG) frequency were determinants of HbA1c levels. • Adherence to insulin boluses and SMBG is particularly challenging in adolescents. What is New: • In adolescents on insulin pump therapy, each additional insulin bolus, particularly around mealtime, was significantly associated with approximately 3 mmol/mol lower HbA1c levels. • This beneficial effect of mealtime bolusing was strongest for the evening meal.