Endocrine Abstracts

Background: Suboptimal adherence to insulin treatment is a main issue in adolescents with type 1 diabetes (T1D). However, to date, there are no available data on adherence to adjunct non-insulin medications in this population. The aims of this study were to assess adherence to ACE inhibitors and statins and explore potential determinants in adolescents with T1D in the context of a clinical trial.

Methods: 443 adolescents (aged 10–16 years) were recruited into the Adolescent Type 1 Diabetes cardio-renal Intervention trial (AdDIT) and exposed to treatment with two oral drugs: an ACE inhibitor, a statin, combinations of both or placebo for 2–4 years. Adherence was assessed every 3 months with the Medication Event Monitoring System (MEMS) and pill count. The effect on adherence of baseline age, diabetes duration, age at diagnosis, HbA1c, method of insulin administration, country and sex were assessed.

Results: Median adherence during the trial was 80.2% (interquartile range: 63.6–91.8), based on MEMS, and 85.7% (72.4–92.9) based on pill count. Adherence dropped from 92.9% at the first visit to 76.3% at the last visit. Adherence was lower in participants with an HbA1c >85 mmol/mol (69.4 [50.8–87.1]%) vs those with an HbA1c 58–85 mmol/mol (79.5 [63.3–91.0]%) and <58 mmol/mol (88.1 [75.5–93.9]%), P=0.001. Adherence varied across the three countries involved in the AdDIT trial: Australia (83.4[70.1–92.9]%), UK (78.9 [61.7–91.6]%) and Canada (73.8[56.8–88.3]%), P for trend= 0.001. There was also a trend for a decreasing adherence with age (P=0.07).

Conclusions: We report a good adherence rate with ACE inhibitors and statins in adolescents with T1D. Older age and higher HbA1c predicted adolescents with worse adherence, highlighting two key potential targets for strategies aiming at improving adherence. Adherence also differed by countries likely reflecting differences in practice or approaches between countries. On behalf of the Adolescent type 1 Diabetes cardio-renal Intervention Trial (AdDIT) study group.