Despite the fact that ADHD comorbidity has been widely studied, some issues remain unsolved.
Individuals with ADHD frequently have sleep disturbances, daytime sleepiness, and/or circadian rhythm abnormalities.
Problems with sleep can also lead to the development of ADHD or ADHD-like symptoms, potentially resulting in misdiagnosis. The effects of restricted, disordered, or disturbed sleep can manifest as symptoms, behaviors, or functional impairments that are remarkably similar to those of ADHD. Comorbid disorders, recognized or unrecognized, may also complicate the treatment process.
Primary sleep disorders should be ruled out before initiating ADHD medication.
ADHD frequently co-occurs with primary sleep disorders such as restless legs syndrome, sleep apnea, increased nocturnal motor activity, and insomnia.
ADHD patients experience much higher rates of sleep problems than their peers without ADHD.
The prevalence of sleep disturbances in individuals with ADHD is reported to be in the range of 25% – 55 %.
The reported prevalence rates differ according to the subtype of ADHD, with a higher prevalence in the combined subtype and in patients with psychiatric comorbidity, which increases the risk of occurrence of sleep disorders.
The association of sleep with ADHD is multifaceted and complex. Objective measures (polysomnography, actigraphy, and multiple sleep latency tests) and subjective measures (e.g., parent- or self-rated questionnaires and diaries) are used to assess sleep in patients with ADHD. Hvolby, A. (2014). Associations of sleep disturbance with ADHD: implications for treatment. ADHD Attention Deficit and Hyperactivity Disorders, 7(1), 1–18. Snitselaar, M. A., Smits, M. G., van der Heijden, K. B., & Spijker, J. (2016). Sleep and Circadian Rhythmicity in Adult ADHD and the Effect of Stimulants. Journal of Attention Disorders, 21(1), 14–26.