Relationships Between Executive Function Improvement and ADHD Symptom Improvement With Lisdexamfetamine Dimesylate in Adults With ADHD and Executive Function Deficits: A Post Hoc Analysis.

Abstract

Executive function (EF) deficits are not generally considered synonymous with attention-deficit/hyperactivity disorder (ADHD). Evidence suggests stimulants improve ADHD symptoms and EF deficits in adults with ADHD, but the relationships between improvements in these domains have not been studied. These post hoc analyses used data from a 10-week double-blind, placebo-controlled study of adults with ADHD and EF deficits treated with lisdexamfetamine dimesylate (30-70 mg) or placebo conducted from May 2010 to November 2010. Efficacy endpoints included change from baseline at week 10/early termination (ET) in self-report Behavior Rating Inventory of Executive Function-Adult Version (BRIEF-A) Global Executive Composite (GEC) T-score and ADHD-Rating Scale with Adult Prompts total score (ADHD-RS-AP-TS). Relationships between ADHD symptom and EF changes were examined using recursive path analyses. Mediation proportions were 0.62 (indirect and total treatment effect coefficients [95% CI]: -6.85 [-9.83 to -3.86] and -11.12 [-14.88 to -7.37]) for self-report BRIEF-A GEC T-score change from baseline at week 10/ET on ADHD-RS-AP-TS change from baseline at week 10/ET and 0.93 (indirect and total treatment effect coefficients [95% CI]: -10.34 [-14.11 to -6.57] and -11.18 [-15.80 to -6.55]) for ADHD-RS-AP-TS change from baseline at week 10/ET on self-report BRIEF-A GEC T-score change from baseline at week 10/ET. Although these data suggest ADHD symptom and EF deficit improvement following lisdexamfetamine are interdependent, it is advantageous to use measures like the BRIEF-A to assess stimulant effects on the wide range of EF deficits associated with ADHD that are not captured by the ADHD-RS-AP alone. Data used in this secondary analysis came from ClinicalTrials.gov identifier: NCT01101022.