Sleep problems are particularly common with ADHD. Sleep disorders occur more frequently in persons with ADHD than in their non-affected twin siblings. The severity of the sleep problems correlates with the severity of the ADHD symptoms. If the ADHD remits, the sleep problems normalize
Problems falling asleep are often caused by constant brooding and a never-ending stream of thoughts. Audio books or a low dose of stimulants can help some people with ADHD to fall asleep. Problems sleeping through the night are also common with ADHD, but problems falling asleep are more frequent. Daytime sleepiness is about twice as common in adults as problems sleeping through the night. Alcohol consumption can promote problems sleeping through the night. Internal tension and stress can also lead to sleep problems such as limb twitching or back pain.
Sources speak of:
- between 12.7% of children between the ages of 7 and 11 with ADHD, 55% and 70 to 80% of all children with ADHD
- between 29% (compared to 2.3% of those not affected) and 44.4% of adults with ADHD,
- 43% of people with ADHD (difficulty falling asleep or sleeping through the night).
- 75% of children and adults with ADHD
- 6.2 times higher probability of clinically increased sleep problems in adolescents with ADHD
- A single study found no changes to sleep architecture in ADHD.
- Use of sleeping pills increased 3-fold (61.4% vs. 20.2%) in adults with ADHD, regardless of subtype.
- Nightmares 3 times as often
- circadian rhythm shifted backwards in 78% of people with ADHD.
- a meta-analysis of k = 13 studies found that adults with ADHD differed significantly from non-affected individuals on the Newcastle-Ottawa Scale:
- in seven of nine subjective sleep parameters (SMD 0.56 to1.55)
- in two of five actigraphic sleep parameters
- Sleep onset latency: SMD 0.80
- Sleep efficiency SMD 0.68
- but not in the polysomnographic sleep parameters
Adolescents with ADHD have a higher variability of sleep problems per person than adolescents without ADHD. These relate to bedtime, waking time, sleep duration, sleep onset latency, sleep quality and night waking times.
Sleep problems should be treated with special attention and priority in the case of ADHD. If sleep problems occur together with (or are caused by) ADHD, a mutually reinforcing vicious circle can easily develop.
Further information on sleep problems can be found here:
1. Sleep problems with ADHD - the symptoms¶
The purpose of sleep is to initially store what was experienced during the day in the hippocampus in the cortex (as a buffer) (first half of the night) and to process it from there and assign it to the individual thematic complexes relating to the experiences. During the day, experiences to be stored in this way are “labeled” with beta-amyloids. These must be broken down in the second half of the night. If the sleep is impaired or too short, beta-amyloid degradation remains incomplete. Consequences of this are memory problems.
98% of the time, people are either asleep or awake. People spend only 1 to 2 % of their time in transitional states. The switch between sleep and wakefulness takes place using a flip-flop switch model:
Elements of the flip-flop switch system:
-
Monoaminergic nuclei
- Nucleus coeruleus
- tuberomammillary nucleus
- Raphe cores
-
ventrolateral cores
-
ventrolateral preoptic nucleus (VLPO)
- extended ventrolateral preoptic nucleus (eVLPO)
- Orixin neurons
Sleep state:
- VLPO neurons fire
- this inhibits the monoaminergic nuclei
- this inhibits their inhibition of VLPO
- simultaneously inhibits orexin neurons
- prevents monoaminergic activation that could interrupt sleep
Waking state:
-monoaminergic nuclei inhibit the VLPO
- ends Inhibition of
- monoaminergic nuclei
- Orexin neurons
- pedunculopontine nuclei (cholinergic)
- laterodorsal tegmental nuclei (cholinergic)
Since the VLPO neurons do not have orexin receptors, the orexin neurons reinforce the monoaminergic tone and do not inhibit the VLPO.
The direct mutual inhibition between the VLPO and the monoaminergic nuclei forms a classic flip-flop switch with sharp state transitions, which is, however, relatively unstable. Only the added orexin neurons stabilize the switch and are ultimately the decisive instance.
In men, a reduced basal cortisol level is associated with sleep problems. In women, there was no influence of basal cortisol levels on sleep.
In ADHD, the majority of studies found reduced basal cortisol levels. See under Reduced basal cortisol levels in ADHD In the article Cortisol and other stress hormones in ADHD
This is not consistent with Ridinger’s hypothesis that sleep problems in ADHD might typically be caused by elevated basal cortisol levels.
1.1. Circadian sleep-wake rhythm disorders in ADHD¶
1.1.1. Difficulty falling asleep with ADHD¶
A sleep onset time (sleep onset latency) of between 5 and 30 minutes is normal. Falling asleep within less than 5 minutes of going to bed can be considered a consequence of excessive exhaustion, falling asleep later than 30 minutes can be considered a consequence of increased arousal. Both can be observed in ADHD.
People with ADHD often take much longer to fall asleep. The description of a circle of thoughts is typical. This is likely to correlate with inner restlessness, but may also be due to depressive problems.
Children with ADHD took longer to reach N3 (non-rapid eye movements).
Sleep onset disorders with ADHD affected
* 11 % of people with ADHD (n = 27)
* Increased 2.5-fold
* 66.8 % of people with ADHD
* 79.7 % for ADHD-C
* 55.6 % for ADHD-I
* 28.8 % of those not affected
Many people with ADHD report that audiobooks help them to fall asleep better. A small immediate release dose of stimulants (1/4 to 1/2 of a single daily dose) can help a small but not insignificant proportion of people with ADHD to fall asleep.
1.1.1.1. Sleep phase shift (later sleep rhythm) / Circadian rhythm and ADHD¶
Circadian problems are associated with a wide range of mental disorders, including ADHD, ASD, anxiety and depression. The population prevalence is between 1% and 16%.
Some people argue that ADHD - at least for a subgroup of people with ADHD - is primarily the result of a shifted chronorhythm.
This may be true for a subgroup. Likewise, most people with ADHD with a chronobiorhythm that is shifted backwards would benefit greatly if the shift could be reduced or eliminated. However, it must be borne in mind that the chronorhythm is largely controlled by life circumstances and lifestyle habits. In the corona pandemic, a shift of the chronorhythm backwards was observed in 2/3 of the test subjects during quarantine and home office. Both bedtime and wake-up time were delayed. At the same time, the quality of sleep deteriorated. For a good 16%, working from home led to a complete deregulation of the chronobiorhythm.
There are several points of contact between the neurophysiological regulation of the circadian rhythm on the one hand and ADHD on the other.
ADHD often shows an altered sleep rhythm. Up to 75% of children and adults with ADHD suffer from a shifted chronobiorhythm. A small study of adolescents with ADHD found delayed sleep phase syndrome (DSPS) in 33% of people with ADHD and 27% of those without
In a small study, people with ADHD with a pronounced later sleep rhythm (“eveningness”, owls) showed increased self-assessment scores of inattention and sleepiness during the day as well as slower reaction times than people with ADHD with an early circadian rhythm (“morningness”, larks). The severity of the overall symptoms did not differ.
Eveningness correlated in studies
- (unlike problems falling asleep and insomnia) with shortened telomeres of the leukocytes, which actually correlates with a higher biological age.
- Whether eveningness correlates with subtypes is unclear
- A large study found eveningness more common in ADHD without hyperactivity:
-
ADHD-I: 47.5 %
-
ADHD-C: 41.5 %
-
ADHD-HI: 30.5 %
- A small Norwegian study of adults with ADHD found strong eveningness significantly more common in ADHD-HI / ADHD-C than in ADHD-I
- 2.4 times more likely to have an obese BMI than morningness (independent of ADHD). In addition, higher BMI values correlated with increased levels of ODD and ADHD.
- With increased sleep problems and increased daytime sleepiness, regardless of the duration of night-time sleep.
- With a birth during long periods of light (June, July), with a significantly lower prevalence for a birth date in December or January. Together with other studies, this strongly indicates a clear imprinting in the first months of life.
- With little time spent outdoors. People who typically spend their day outdoors go to bed earlier and sleep longer than people who typically spend their day indoors.
- With the latitude of the place of residence / growing up. There is a higher prevalence of ADHD in countries and geographical areas with lower sun intensity and thus less adjustment to day and night by the central biological clock
- Contradictory results are available on the question of whether carriers of DRD4-7R, a gene variant of the dopamine D4 receptor gene, are more frequently affected by ADHD, especially if they were born in spring or summer. It is conceivable that the contradictions are resolved when it is taken into account that people with a northern genetic background react less sensitively to variations in sunlight intensity.
Excessive daytime stress, as can occur as a result of ADHD due to the impaired stimulus filter, can lead to an early small melatonin peak in the early evening (twilight sleepiness). This short melatonin peak around 6 / 7 pm is followed by a drop in melatonin to zero around 9 pm.
1.1.1.2. Delayed increase in melatonin in the evening¶
The evening rise in melatonin is often delayed in people with ADHD as well as in people with sleep problems. In children between the ages of 6 and 12 with ADHD and sleep problems, the onset of sleep was delayed by 50 minutes compared to children with ADHD without sleep problems, which corresponded to the delay in the rise in melatonin. Otherwise, sleep did not differ significantly.
As the start of school and consequently the time when children get up is the same for all children, this explains why people with ADHD with sleep problems get less sleep and therefore have additional difficulties in everyday life.
In people with delayed sleep-wake phase disorder, the melatonin peak is shifted back by 2 to 6 hours. The study found a shift of around 5 hours, from 00:30 to 05:30. At the same time, the increase in melatonin levels was somewhat flatter.
1.1.1.3. Increased risk of winter depression¶
According to a survey by Kooij, people with a delayed circadian rhythm are more likely to suffer from winter depression.
1.1.2. Sleep disorders with ADHD¶
Waking up during the night, often after 3 to 4 hours of sleep. Difficulty sleeping through the night is one of the most common sleep disorders in ADHD.
However, according to our personal impression and the data from the ADxS.org symptom test, problems falling asleep are slightly more common and daytime sleepiness occurs about twice as often (at least in adults)
Sleep-through problems in toddlers 1 to 3 years old were a stronger predictor of a later ADHD diagnosis than sleep duration.
Problems sleeping through the night can be caused by increased alcohol consumption, which is more common in ADHD, among other things to promote falling asleep. In addition, problems sleeping through the night, such as back pain or teeth grinding, appear to be influenced by excessive inner tension.
1.1.3. Reduced sleep duration and ADHD¶
One meta-study found a correlation between shortened sleep duration and ADHD symptoms, particularly hyperactivity. Another study found no correlation between the ADHD polygenic disc score and sleep duration measured via actigraphy, although parents reported a correlation between ADHD symptoms and shortened sleep duration.
Increasing the duration of sleep significantly improved inhibition in children with ADHD.
A sleep duration of less than 6 hours is 3.5 times more common in people with ADHD:
- 26.6 % of people with ADHD
- 34.7 % for ADHD-HI and ADHD-C
- 22.2 % for ADHD-I
- 7.5 % of those not affected
Interestingly, children’s sleep time has steadily decreased over the last few decades. The evening bedtime for three-year-olds was 19:08 in 1974, 19:53 in 1979 and 20:07 in 1986.
in 1985, 10- to 15-year-old children slept 30 minutes more per night than their peers in 2005, with earlier sleeping times in 1985.
A large analysis of 690,747 children showed that sleep duration decreased by 0.75 minutes per year from 1905 to 2008, and by a total of 1:15 hours over 100 years. Furthermore, a meta-analysis of 20 studies showed that the likelihood of obesity in ADHD-HI correlated with shorter sleep duration in children.
1.2. Sleep-related breathing disorders in ADHD¶
Breathing interruptions during sleep (obstructive sleep apnea) are often a cause of ADHD-like symptoms.
In chronic adenotonsillar hypertrophy, adenotonsillectomy improves any or suspected ADHD symptoms.
High weight increases the likelihood of sleep apnea.
Sleep apnea appears to be associated with a higher likelihood of ADHD in adults.
ADHD is often accompanied by sleep disorders.
- Obstructive sleep apnea is common in ADHD
- 3.6-fold increase in ADHD (sleep apnea and snoring)
- 41 % of people with ADHD (n = 27) n = 27)
A test for sleep apnea does not require an overnight stay in a sleep laboratory. Sleep physicians give people with ADHD a device to take home, wear it for one night and return it the next day. The recorded data reliably indicates breathing problems during sleep.
Insomnia, RLS, and frequent snoring appear to be significant predictors of subsequent ADHD-HI symptoms.
1.3. Sleep-related movement disorders and ADHD¶
Restless legs syndrome (RLS). RLS symptoms, insomnia and frequent snoring appear to be significant predictors of subsequent ADHD-HI symptoms.
Periodic Leg Movement Syndrome (PLMS) is increased movement activity, especially in the second half of sleep. As a result, people with ADHD wake up more frequently.
Sleep-related movement disorders are increased in ADHD.
* 22 % of people with ADHD (n = 27)
* RLS 14.5-fold increased
* More common in ADHD-HI / ADHD-C than in ADHD-I
1.4. Narcolepsy¶
Narcolepsy is a common comorbidity of ADHD.
Narcolepsy has the following symptoms:
- Excessive daytime sleepiness (ETS)
-
Cataplexy
- Hypnagogic and hypnopompic hallucinations.
- Sleep paralysis
- Disturbed sleep at night (due to increased arousal)
More than 10% of people with ADHD show all symptoms.
Cataplexy occurs 11 times more frequently in people with ADHD than in those not affected.
1.5. Severe daytime sleepiness and ADHD¶
Problems with severe daytime sleepiness or increased sleepiness are sometimes observed in people with ADHD.
Daytime sleepiness occurs 3 times more frequently in people with ADHD than in those not affected. 50% of people with ADHD have daytime sleepiness.
Sleep deprivation causes greater fatigue in people with ADHD than in people without ADHD. Persons with ADHD are therefore more sensitive to sleep deprivation than people without ADHD.
One study found a correlation of daytime sleepiness and cognitive problems in ADHD.
In this case, treatment with modafinil is the obvious choice.
Orexin levels should also be checked. More on this at*⇒ Orexin / hypocretin* Modafinil apparently increases orexin levels. This could be one of the pathways of action of modafinil in the treatment of narcolepsy.
The selective D1 receptor agonist SKF38393 was able to improve excessive daytime sleepiness and restore REM sleep in animal studies.
1.6. Prolonged REM sleep¶
6 studies found prolonged REM sleep in people with ADHD, two studies found shortened REM sleep, one found shortened REM sleep in ADHD when sleep duration was reduced.
1.7. Slow-wave sleep for ADHD¶
Some studies have found an increased proportion of slow-wave sleep within and outside of REM sleep phases in ADHD.
One study found one and a half times the duration of slow-wave sleep in adults with ADHD:
-
ADHD: 68.3 minutes
- Non-ADHD: 43.4 minutes
One study reports a reduced percentage of slow-wave sleep
1.8. Bruxism and sleep¶
Possible bruxism during sleep and wakefulness was associated with hyperactivity and impulsivity.
1.9. Other sleep disorders with ADHD¶
The following other, less common sleep disorders were found in children with ADHD.
- Sleep-related epileptiform discharges
- 22 % of people with ADHD (n = 27) n = 27)
- Narcolepsy-like phenotype
- 7 % of people with ADHD (n = 27) n = 27)
-
Arousal Disorder
- 4 % of people with ADHD (n = 27) n = 27)
2. Sleep problems in ADHD with subtypes and comorbidities¶
2.1. Sleep problems correlate with emotional dysregulation and attention problems¶
A large study (n = 4,109) of children aged 0 to 7 years found that people with ADHD have more sleep problems and, consequently, more problems with emotional dysregulation and attention than people without ADHD. At the same time, it was found that sleep problems also lead to emotional dysregulation and attention problems in those not affected. However, sleep problems are not the trigger for later attention problems.
Whether there is a connection between shortened sleep and subtypes is unclear.
- Sleep duration decreased with increasing intensity of inattention symptoms, while hyperactivity/impulsivity showed no correlation with sleep duration
- Sleep duration problems more likely in ADHD-HI / ADHD-C than in ADHD-I
Problems sleeping through the night are common in depression. They are a typical symptom of the internalizing depression subtypes (melancholic or psychotic depression), while daytime sleepiness correlates strongly with the externalizing subtype of atypical depression. In ADHD, the various sleep problems do not appear to correlate as clearly with specific ADHD presentations (formerly subtypes). Data from the ADxS symptom test (as of June 2020, n = 1,889) show that daytime sleepiness is the most common sleep problem in adults with ADHD (about twice as common as problems falling asleep or sleeping through the night) and is slightly more common in ADHD-I than in ADHD-HI and ADHD-C. Problems falling asleep are more common than problems sleeping through the night. Problems falling asleep and sleeping through the night are also more common in ADHD-HI and ADHD-C than in ADHD-I.
2.2. Sleep problems and ADHD presentation forms (subtypes)¶
Different results were found for the frequency of sleep problems among the subtypes.
- more common with ADHD-C
- more frequent ADHD-HI and ADHD-C than ADHD-I
- more frequent problems sleeping through the night with ADHD-HI
- more common with ADHD-I
- no differences between the subtypes,
- however, gender-specific and comorbidity-specific differences were found: 75% of girls and 53% of boys with ADHD had sleep problems. Anxiety symptoms were clearly correlated with later bedtime and sleep terrors, hyperactive-impulsive symptoms were associated with more frequent night-time awakenings and more sleep behavior disorders (parasomnia). ODD and depressive symptoms correlated with shorter sleep duration. Depression was clearly reflected in increased daytime sleepiness and general sleep problems. Gender did not moderate the correlation between comorbidities and sleep problems. Another study found a correlation between unstable sleep and inattention in boys with ADHD.
One study found that sleep problems in ADHD only occurred in people with ADHD with sensitivity problems (taste and smell sensitivity, hearing sensitivity and sensation seeking) according to the Short Sensory Profile (SSP) questionnaire.
In adults with ADHD, higher levels of ADHD severity and with medical or psychiatric comorbidities (especially depression, anxiety disorders, personality disorders, and any type of substance use disorder) further increased sleep problems.
3. Sleep problems as symptoms of stress¶
Sleep disorders are very common symptoms of severe stress.
Increased alertness and reduced deep sleep is a direct effect of the stress hormone CRH.
Frequent nightmares are also mentioned as a stress symptom.
