Variable Patterns of Remission From ADHD in the Multimodal Treatment Study of ADHD

Abstract

Objective: It is estimated that childhood attention deficit hyperactivity disorder (ADHD) remits by adulthood in approximately 50% of cases; however, this conclusion is typically based on single endpoints, failing to consider longitudinal patterns of ADHD expression. The authors investigated the extent to which children with ADHD experience recovery and variable patterns of remission by adulthood.

Methods: Children with ADHD (N=558) in the Multimodal Treatment Study of ADHD (MTA) underwent eight assessments over follow-ups ranging from 2 years (mean age, 10.44 years) to 16 years (mean age, 25.12 years) after baseline. The authors identified participants with fully remitted, partially remitted, and persistent ADHD at each time point on the basis of parent, teacher, and self-reports of ADHD symptoms and impairment, treatment utilization, and substance use and mental disorders. Longitudinal patterns of remission and persistence were identified that considered context and timing.

Results: Approximately 30% of children with ADHD experienced full remission at some point during the follow-up period; however, a majority of them (60%) experienced recurrence of ADHD after the initial period of remission. Only 9.1% of the sample demonstrated recovery (sustained remission) by study endpoint, and only 10.8% demonstrated stable ADHD persistence across study time points. Most participants with ADHD (63.8%) had fluctuating periods of remission and recurrence over time.

Conclusions: The MTA findings challenge the notion that approximately 50% of children with ADHD outgrow the disorder by adulthood. Most cases demonstrated fluctuating symptoms between childhood and young adulthood. Although intermittent periods of remission can be expected in most cases, 90% of children with ADHD in MTA continued to experience residual symptoms into young adulthood.

Trial registration: ClinicalTrials.gov NCT00000388.

Keywords: ADHD; Neurodevelopmental Disorders; Remission; Symptoms; Treatment.

Figures

Figure 1.

Longitudinal and cross-sectional patterns of remission, recovery, and persistence in the Multimodal Treatment Study of ADHD Note. Bar graphs indicate cross-sectional estimates for persistence, partial remission, and full remission; line graphs display longitudinal patterns by time point. We defined recovery as untreated full remission of ADHD that persisted for at least two consecutive assessments without being followed by an episode of recurrence (i.e., full remission continued until study endpoint). Therefore, the green line represents the percentage of participants who had experienced onset of recovery by the corresponding time point. Individuals were classified as displaying stable persistence if they demonstrated persistent ADHD for all assessments to date in the follow-up period. Therefore, the red line represents the percentage of participants who continued to demonstrate stable persistence at a given timepoint. Stable partial remission was defined as displaying one classification change from persistent ADHD to partial remission that maintained until study endpoint. Therefore, the yellow line represents the percentage of participants who had experienced onset of stable partial remission by the corresponding time point. A fluctuating pattern indicated at least two changes to cross-sectional classification since baseline diagnosis of ADHD, in the absence of the recovery pattern. Therefore, the blue line represents the percentage of participants who meet criteria for fluctuating status at a given time point (which precludes also meeting criteria for recovery at any future time point).

Figure 2.

Sample Cases with Fluctuating and Recovery Patterns of Remission Note. Case A demonstrated clinically significant impairment during the 2-year (age 9.42), 3-year age 11.11), 8-year (age 16.10), 10-year (age 17.87), and 16-year (age 24.11) assessments and was treated with methylphenidate during the 8-year assessment (age 16.10) and with atomoxetine during the 14-year assessment (age 21.76). Case B demonstrated clinically significant impairment during the 2-year (age 10.15) through 10-year (age 18.06 assessment) and was treated with methylphenidate during the 2-year, 3-year, and 6-year assessments (ages 10.15 through 14.31), classroom behavioral intervention for ADHD at the 3-year assessment (age 11.02), and attended a special school for ADHD at the 8-year assessment (age 16.28).

Figure 2.

Sample Cases with Fluctuating and Recovery Patterns of Remission Note. Case A demonstrated clinically significant impairment during the 2-year (age 9.42), 3-year age 11.11), 8-year (age 16.10), 10-year (age 17.87), and 16-year (age 24.11) assessments and was treated with methylphenidate during the 8-year assessment (age 16.10) and with atomoxetine during the 14-year assessment (age 21.76). Case B demonstrated clinically significant impairment during the 2-year (age 10.15) through 10-year (age 18.06 assessment) and was treated with methylphenidate during the 2-year, 3-year, and 6-year assessments (ages 10.15 through 14.31), classroom behavioral intervention for ADHD at the 3-year assessment (age 11.02), and attended a special school for ADHD at the 8-year assessment (age 16.28).