Improvements in Executive Function Correlate with Enhanced Performance and Functioning and Health-Related Quality of Life: Evidence from 2 Large, Double-Blind, Randomized, Placebo-Controlled Trials in ADHD

Abstract

Objective: To assess whether improvement in executive function correlates with perceived improvement in health-related quality of life (HRQOL) in adults with attention-deficit/hyperactivity disorder (ADHD) who are treated with stimulant medication. Methods: We collected data on executive function and HRQOL using the Brown Attention-Deficit Disorder Scale (BADDS) and the ADHD Impact Module–Adult (AIM-A) during 2 large, randomized, double-blind, placebo-controlled trials evaluating the use of the triple-bead mixed amphetamine salt (MAS) SPD465 as stimulant pharmacotherapy for ADHD. BADDS and AIM-A data were collected at baseline and at study endpoint, and changes from baseline were assessed. Correlation coefficients for BADDS and AIM-A were calculated at baseline and endpoint for each study. Results: The change from baseline in BADDS total score was –14.8 ± 24.49 in Study 1 (dose optimization strategy) and –26.1 ± 28.54 in Study 2 (forced-dose titration strategy), demonstrating substantial reported improvement in executive function. In both studies, improvement was reported for all 5 BADDS clusters at study endpoint versus baseline. While improvement was reported for all 6 AIM-A scales at study endpoint versus baseline, the most substantial change from baseline in AIM-A scores over the course of the studies was in Performance and Function (Study 1, +15.2 ± 25.68; Study 2, +26.3 ± 28.17). There was significant correlation of the BADDS total score with the AIM-A Performance and Function scale (Study 1, –0.6723; Study 2, –0.6982), and strong correlations were observed between each of the 5 individual clusters of BADDS and AIM-A performance and function in both studies. Conclusions: Reported improvement in executive function correlates with reported improvement in HRQOL as assessed in 2 independent clinical trials in which participants received either placebo or triple-bead MAS for the treatment of ADHD. In particular, there were strong correlations between all 5 individual clusters of BADDS and the AIM-A Performance and Function scale. [Trial registration: ClinicalTrials.gov, Identifier: NCT00150579 and NCT00152022]

Keywords:

• attention-deficit/hyperactivity disorder
• executive function
• health-related quality of life
• mixed amphetamine salts