ADHD as a circadian rhythm disorder: evidence and implications for chronotherapy
a day ago
- Circadian rhythm dysfunction is highly prevalent in ADHD, affecting 73-80% of patients, with evening chronotype and phase-delayed biological markers.
- Sleep disturbances are severe: insomnia affects up to 80% of adults and 82% of children with ADHD; delayed sleep-wake timing occurs in up to 78%; DLMO is delayed by 45 minutes in children and 90 minutes in adults.
- Biological markers include delayed and blunted cortisol rhythms, reduced pineal volume, and attenuated BMAL1/PER2 clock-gene rhythms.
- Interventions such as melatonin and bright light therapy successfully advance circadian phase in ADHD, with some trials showing symptom improvement.
- Behavioral sleep interventions improve ADHD symptoms and sleep in children; multimodal protocols for evening chronotypes show promise and warrant testing in ADHD.