HOLLYWOOD, FLA. – Pharmacologic treatment of parental attention-deficit/hyperactivity disorder might provide a novel means of improving parenting skills while reducing inappropriate behaviors in their unmedicated children with the disorder, according to Dr. James G. Waxmonsky.
In a structured study conducted by formally trained evaluators in a university family behavioral sciences center, treatment of parental ADHD with lisdexamfetamine dimesylate (Vyvanse) not only resulted in the expected reduction in parental ADHD symptoms, but was also associated with improved parenting performance and more harmonious child behavior in the laboratory setting, he reported at a meeting of the New Clinical Drug Evaluation Unit sponsored by the National Institute of Mental Health.
Parents on ADHD medication gradually increased their use of praise over time by fivefold, while those on placebo did not change their use of praise. The parents on lisdexamfetamine dimesylate (LDX) also were significantly more verbally responsive to their child. There was less negative talk. Parents issued fewer commands, as well.
Dr. James G. Waxmonsk
Even before the treated adults’ parenting performance began to show objective improvement, their children displayed a reduction in inappropriate and oppositional behaviors during joint homework assignments and other observed interactions.
"Most effects emerged several weeks into treatment with the optimal dose. The strength of effects on parenting behaviors paralleled that seen in trials of established parent training programs, while the degree of improvements in children’s oppositional behaviors matched that seen with stimulant medication," according to Dr. Waxmonsky, a child and adolescent psychiatrist serving as medical director of the center for children and families at Florida International University, Miami.
He presented a study involving 38 parents who met full DSM-IV criteria for ADHD and who also had a 5- to 15-year-old child with ADHD. The parents were started on LDX at 30 mg/day, titrated over the next several weeks to a maximum of 70 mg/day or until occurrence of at least a 30% reduction in scores on the ADHD Rating Scale. The mean optimized drug dose was 50 mg/day, with an average 58% reduction in ADHD Rating Scale score severity.
Once the medication was optimized, the parent and child were assessed using the Dyadic Parent-Child Interaction Coding System in the behavior laboratory on two occasions 1 week apart. In these sessions, the parent and child collaborated on a simulated homework task as well as an age-appropriate nonacademic task such as joint play or planning a family activity. In the first session, the blinded parent was on medication; for the second session, on placebo. The child with ADHD remained unmedicated throughout the study.
Significant improvement in parental ADHD symptoms was noted after just 1 week on the optimal medication dose. But in the initial pair of evaluations, the first of which was conducted when parents had been on their optimal drug dose for just 1-2 weeks, there was no significant difference between parenting behaviors when the parents were on and off medication.
In contrast to the lack of change in parenting behaviors during this initial study phase, significant reductions in the children’s inappropriate behavior during the homework task was documented when the parent was on LDX versus placebo. One plausible explanation for this observation is that a reduction in parental ADHD symptoms triggers improved child behavior. Then, as parents note improvements in their child’s behavior, they might respond by engaging in more positive parenting behaviors, in turn fostering further improvement over time in their child’s behavior. That would account for what was seen later in the study, Dr. Waxmonsky said.
In phase II of the study, the blinded parents were randomized to 8 weeks of optimized medication or placebo, followed by another evaluation of parent-child interaction in the behavior lab. This time, striking improvements in parenting performance were evident in the adults on extended duration of optimized medication compared with those on placebo. Moreover, the improvements in the behavior of the children whose parents were on LDX compared with that of the kids whose parents were on placebo were even larger than those seen in the first phase of the study. For example, children whose parents had been on optimized LDX for 8 weeks showed a fourfold greater reduction in inappropriate and oppositional behaviors than did children of parents on placebo.
The chief limitation of this in-depth study, Dr. Waxmonsky, is its small size. Almost none of the participating parents had ever been on anti-ADHD medication before; 10 of the 38 dropped out because of medication side effects, most prominently appetite loss, insomnia, and headaches.
The study was funded by a research grant from Shire Pharmaceuticals.