Insights from 24-hour actigraphy using functional linear modeling in children with and without ADHD

Area of Science:

• Neuroscience
• Child Psychology
• Sleep Medicine

Background:

• Attention-deficit/hyperactivity disorder (ADHD) is frequently associated with sleep disturbances and circadian rhythm alterations.
• Comprehensive 24-hour motor activity patterns in ADHD remain understudied.
• Predictors and correlates of hyperactivity patterns in ADHD are largely unknown.

Purpose of the Study:

• To investigate 24-hour motor activity patterns in children with ADHD using functional linear modeling (FLM).
• To explore differences in activity patterns between ADHD presentations (combined vs. inattentive).
• To identify correlates and predictors of 24-hour activity profiles in children with and without ADHD.

Main Methods:

• Utilized 24-hour actigraphy for two weeks in 74 children (35 ADHD, 39 controls) aged 6-12 years.
• Applied functional linear modeling (FLM) to analyze actigraphy data.
• Conducted post-hoc correlational analyses to examine associations with chronotype, early regulation, and daylight exposure.

Main Results:

• No significant overall 24-hour actigraphy differences were found between children with and without ADHD.
• Significant differences in activity patterns emerged between ADHD presentations (combined vs. inattentive) around sleep onset on free days.
• In the ADHD group, activity profiles correlated with chronotype and early regulation; in controls, with daylight exposure.

Conclusions:

• Comprehensive 24-hour FLM analysis reveals subtle differences in activity patterns between ADHD presentations, not captured by traditional sleep-onset latency measures.
• Actigraphy, particularly when analyzed with FLM, may offer complementary insights into ADHD-related alterations.
• Actigraphy could serve as a valuable supplementary diagnostic tool in clinical ADHD assessments, despite medication use in the study sample.