Time Course and Predictors of Health-Related Quality of Life Improvement and Medication Satisfaction in Children Diagnosed with Attention-Deficit/Hyperactivity Disorder Treated with the Methylphenidate Transdermal System

Abstract

Objective: The aim of this study was to evaluate the time course and predictors of improvement in health-related quality of life (HRQL) and medication satisfaction in children diagnosed with attention-deficit/hyperactivity disorder (ADHD) and treated with the methylphenidate transdermal system (MTS). Methods: Temporal relationships between ADHD symptoms, medication satisfaction, and HRQL measures were examined via latent growth curve, structural path, and growth mixture models. Results: Higher levels of medication satisfaction at the end of titration predicted greater increases in family HRQL (p = 0.004) and, to a lesser extent, child HRQL (p = 0.068) throughout the study. At 4 of 6 (p < 0.05) and 5 of 6 (p < 0.10) contemporaneous time points, ADHD symptoms predicted child HRQL. At 2 of 6 (p < 0.05) and 3 of 6 (p < 0.10) contemporaneous time points, ADHD symptoms predicted family HRQL. ADHD did not predict child or family HRQL improvements at subsequent time points. A uniform pattern of change for child HRQL was noted, with most HRQL change following the pattern of symptom change during titration. Three distinct patterns of change were noted for family HRQL. Conclusions: In most cases, medication satisfaction, ADHD symptoms, and HRQL improved simultaneously, suggesting that HRQL was not a delayed response to improvement in symptoms. Children showed a uniform pattern of improvement in HRQL that followed symptom change; three distinct patterns of change were found for improvement in family HRQL. Clinical Trial Registry: #NCT00151970.