Changes in Treatment Adherence and Glycemic Control During the Transition to Adolescence in Type 1 Diabetes

OBJECTIVE: To test models of unidirectional and bidirectional change between treatment adherence and glycemic control in youth with type 1 diabetes. RESEARCH DESIGN AND METHODS: We conducted a 2-year longitudinal, multisite study of 225 youth with type 1 diabetes recruited at the cusp of adolescence (aged 9–11 years) to describe the mutual influences of glycemic control as measured by HbA(1c) and treatment adherence as measured by blood glucose monitoring frequency (BGMF) during the transition to adolescence. RESULTS: HbA(1c) increased from 8.2 to 8.6% (P < 0.001) and BGMF decreased from 4.9 to 4.5 checks per day (P < 0.02) during the 2-year period. Changes in the BGMF slope predicted changes in HbA(1c). A change (increase) in HbA(1c) was associated with a change (decrease) in BGMF of 1.26 (P < 0.001) after controlling for covariates. CONCLUSIONS: The magnitude of the effect of declining treatment adherence (BGMF) on glycemic control in young adolescents may be even greater than declines observed among older adolescents. BGMF offers a powerful tool for targeted management of glycemic control for type 1 diabetes during the critical transition to adolescence.