Objective: This study examines the effects of parental lisdexamfetamine (LDX) treatment on parent-child interactions.
Methods: Participants were 30 parents (27% were male) and their children aged 5-12 years, both diagnosed with DSM-IV attention-deficit/hyperactivity disorder (ADHD). Optimal LDX dose (30, 50, or 70 mg/day) was determined for parents during a 3-week open-label titration, followed by a within-subjects trial of the acute impact of LDX and placebo on observable parent-child interactions. Two laboratory-based, parent-child interactions simulating typical family tasks (e.g., homework, joint play) were conducted within 2 weeks, once with the adult on a blinded optimal dose of LDX and once on placebo (phase I). Parents were then randomly assigned to continue blinded treatment with LDX or placebo for another month followed by a third interaction task (phase II) to assess the ongoing effects of LDX on parent-child interactions. The primary outcome was the change in rate of parenting behaviors coded during the parent-child interaction tasks. Secondary outcomes included observed rates of children's inappropriate behaviors during the laboratory tasks and changes in parental ADHD symptom severity (ADHD-Rating Scale).
Results: Twenty parents (67%) completed the trial. In phase I, medication was associated with a significant reduction in negative talk by parents (p = 0.0066, d = -0.47). There was a Medication × Task interaction (p = 0.0235) with a reduction in children's negative behaviors in the homework phase only (p = 0.0154, d = -0.58). In phase II, LDX was associated with significant increases in praise by parents (d = 0.81) and reductions in parental commands (d = -0.88) and children's inappropriate behaviors (d = -0.84) (all p-values < 0.05). While not reaching statistical significance, LDX was also associated with large reductions in parental verbalizations (d = -0.82), moderate increases in parental responsiveness (d = 0.55), and large reductions in the ratio of commands to verbalizations during the non-homework task (d = -1.05) (all p-values < 0.10). Significant reductions in parental ADHD symptoms vs. placebo were observed (p < 0.005). Loss of appetite, dry mouth, headaches, and delayed sleep onset were the most common adverse events.
Conclusions: Improvements in parent-child interactions emerged over time with LDX treatment of parental ADHD. Results suggest that pharmacological treatment of parental ADHD may improve outcomes in parents and their children.
Trial registration: ClinicalTrials.gov NCT01127607.