ADHD Linked to Circadian Rhythm Disruption: Evidence and Chronotherapy

Research indicates a strong association between ADHD and circadian rhythm dysfunction, with up to 80% of adults and children with ADHD experiencing sleep disturbances. Key findings include delayed dim-light melatonin onset (DLMO) by 45-90 minutes, blunted cortisol rhythms, reduced pineal volume, and attenuated peripheral clock-gene rhythms. Intervention studies show that melatonin and bright light therapy can advance DLMO, correlating with symptom improvement. The article proposes a clinical pathway involving sleep/circadian screening, chronotype assessment, and behavioral interventions like fixed wake times and light management. Further trials are needed to optimize these circadian-focused protocols.