Insufficient sleep may cause impairments in daytime functioning among teenagers with ADHD, according to findings from a crossover sleep restriction/extension study.
“The need for experimental research examining the impact of sleep in youth with ADHD has recently been identified as a research priority,” Stephen P. Becker, PhD, of Cincinnati Children’s Hospital Medical Center and the University of Cincinnati College of Medicine, and colleagues wrote. “Adolescents are especially prone to shortened sleep, due to a range of biological (eg, circadian clock shifts later associated with the progression of puberty) and environmental (eg, school start time, nighttime technology use) factors.”
Using an experimental crossover design, researchers investigated whether sleep duration was causally associated with sleepiness, inattention and behavioral functioning in teenagers with ADHD. Youth aged 14 to 17 years entered a 3-week sleep protocol that included a phase stabilization week, 1 week of sleep restriction (6.5 hours) and 1 week of sleep extension (9.5 hours).
Researchers monitored sleep with actigraphy and daily sleep diaries and conducted laboratory visits at the end of each week. They analyzed 48 teens with complete actigraphy data and who successfully completed the sleep protocol. Self- and parent-rated daytime sleepiness, ADHD symptoms, sluggish cognitive tempo and oppositional behaviors were examined, as were participants’ responses to the A-X Continuous Performance Test, which measured inattention and impulsivity.
On average, participants experienced 1.6 hours more sleep per night during sleep extension than sleep restriction. During sleep restriction, participants experienced greater actigraphy-measured sleep efficiency, less actigraphy-measured waking after sleep onset, shorter diary-reported sleep-onset latency and greater diary-reported difficulty waking, according to the study.
Participants reported greater daytime sleepiness and were more likely to report napping during sleep restriction compared with sleep extension. Parents reported significantly greater inattention and oppositional behaviors during sleep restriction. In addition, parents and teens both reported significantly greater sluggish cognitive tempo symptoms during sleep restriction. However, teenagers reported significantly less hyperactivity-impulsivity during sleep restriction than sleep extension.
“Our findings have potentially important implications for the treatment of adolescents with ADHD. If shortened sleep duration worsens daytime functioning, then the flip side of the coin is that extended sleep duration improves daytime functioning,” Becker and colleagues wrote. “Sleep should be assessed when treating adolescents with ADHD, and it may be important to directly target sleep in ADHD interventions.” – by Savannah Demko
Disclosures: Becker reports support from the Institute of Education Science, the Cincinnati Children's Research Foundation, and the Secretariat of State for Research, Development and Innovation, Ministry of Economy, Industry and Competitiveness (Spanish Government). Please see the study for all other authors’ relevant financial disclosures.