BACKGROUND: Sleep disturbances may cause distress among individuals with attention-deficit/hyperactivity disorder (ADHD), but few studies have examined the impact of stimulant pharmacotherapy for ADHD on sleep in adults.
METHOD: These post hoc analyses included sleep data collected with the Pittsburgh Sleep Quality Index (PSQI), a self-rated questionnaire, from 831 adults with DSM-IV-TR-defined ADHD in 2 large, randomized, double-blind, placebo-controlled, forced-dose titration studies of lisdexamfetamine (N = 420; conducted from May 25, 2006, to November 16, 2006) and triple-bead mixed amphetamine salts (MAS) (N = 411; conducted from April 25, 2005, to November 4, 2005). Change from baseline to endpoint in PSQI clinically meaningful change categories (ie, "decrease," "no change," or "increase") was analyzed by treatment group in each study using the χ² test. The Cochran-Mantel-Haenszel method was used (1) to determine whether there was a statistically significant difference in Clinical Global Impressions-Improvement (CGI-I) score of 1 or 2 (improved) versus > 2 (not improved) relative to a decrease or an increase in PSQI and (2) to analyze shifts from good sleep at baseline (PSQI ≤ 5) to poor sleep at endpoint (PSQI > 5).
RESULTS: Impaired sleep (PSQI score > 5) relative to baseline was demonstrated in 8.3% and 9.7% of the treatment and placebo groups, respectively (P = .18), in the MAS study and 7.7% and 8.2%, respectively (P = .03), in the lisdexamfetamine study. Clinically meaningful change in baseline to endpoint PSQI was not statistically significantly different between treatment and placebo groups in either study. A significant difference in CGI-I 1 and 2 relative to an increase or decrease in PSQI was found in both the triple-bead MAS (P < .0001) and the lisdexamfetamine (P = .0008) trials. More subjects with improved CGI-I rating of 1 or 2 had improvement in PSQI than had worsening.
CONCLUSIONS: Approximately one-third of subjects receiving treatment or placebo had clinically meaningful sleep improvement, emphasizing that change in sleep quality during treatment may not necessarily be related to stimulant therapy. When managing complaints of sleep difficulties in ADHD subjects, clinicians should undertake a broad assessment and consider underlying conditions that may contribute to sleep disruption.
TRIAL REGISTRATION: clinicaltrials.gov Identifiers: NCT00334880 and NCT00152022.
