The impact of adjunctive guanfacine extended release on stimulant adherence in children/adolescents with attention-deficit/hyperactivity disorder.
To assess stimulant adherence among children/adolescents with attention-deficit/hyperactivity disorder (ADHD) augmenting stimulants with guanfacine extended-release (GXR). Inclusion criteria: 6-17 years, ≥1 ADHD diagnosis, ≥1 long-acting and/or short-acting stimulant with GXR augmentation. Modified medication possession ratio (mMPR; days medication available/days in period, excluding medication holidays) was assessed; mMPR <0.80 nonadherent. Regression models assessed change in mMPR adjusting for demographic and clinical characteristics. Among patients nonadherent to stimulants pre-augmentation (n = 165), unadjusted mean (SD) pre- and post-stimulant mMPRs were 0.68 (0.11) and 0.87 (0.16). Adjusted mean change in mMPR was 0.20 for long-acting versus 0.18 for short-acting stimulants (p = 0.34). Among patients nonadherent to stimulants, GXR augmentation was associated with increased stimulant adherence.