Stimulant-responsive and stimulant-refractory aggressive behavior among children with ADHD

Abstract

Objectives: The objective of this study was to examine factors that are associated with aggression that is responsive versus refractory to individualized optimization of stimulant monotherapy among children with attention-deficit/hyperactivity disorder (ADHD).

Methods: Children who were aged 6 to 13 years and had ADHD, either oppositional defiant disorder or conduct disorder, significant aggressive behavior, and a history of insufficient response to stimulants completed an open stimulant monotherapy optimization protocol. Stimulant titration with weekly assessments of behavior and tolerability identified an optimal regimen for each child. Families also received behavioral therapy. Parents completed the Retrospective-Modified Overt Aggression Scale (R-MOAS) at each visit. Children were classified as having stimulant-refractory aggression on the basis of R-MOAS ratings and clinician judgment. Differences that pertained to treatment, demographic, and psychopathology between groups with stimulant monotherapy-responsive and -refractory aggression were evaluated.

Results: Aggression among 32 (49.3%) of 65 children was reduced sufficiently after stimulant dosage adjustment and behavioral therapy to preclude adjunctive medication. Those who responded to stimulant monotherapy were more likely to benefit from the protocol's methylphenidate preparation (once-daily, triphasic release), showed a trend for lower average dosages, and received fewer behavioral therapy sessions than did children with stimulant-refractory aggression. Boys, especially those with higher ratings of baseline aggression and of depressive and manic symptoms, more often exhibited stimulant-refractory aggression.

Conclusions: Among children whose aggressive behavior develops in the context of ADHD and of oppositional defiant disorder or conduct disorder, and who had insufficient response to previous stimulant treatment in routine clinical care, systematic, well-monitored titration of stimulant monotherapy often culminates in reduced aggression that averts the need for additional agents.

FIGURE 1

Consolidated Standard of Reporting Trial (CONSORT) diagram showing disposition of all participants screened.

FIGURE 2

Distributions of baseline and outcome R-MOAS scores for total sample and stimulant-responsive and stimulant-refractory subgroups. Left column presents baseline values, and right column shows scores at the end of stimulant optimization phase. Top row shows all subjects, middle row children whose aggression remitted with stimulant monotherapy, and the bottom row those whose aggression persisted.

FIGURE 3

Association between stimulant monotherapy aggression-response status and total baseline scores on the YMRS and the CDRS-R.