Poor sleep patterns spark hyperactivity
The more we understand about sleep the more important we realise it is. We now know that disturbed sleep is linked to many serious conditions, such as obesity, diabetes, heart disease and stroke to name but a few.
To that list we can add another condition, ADHD. Research has now revealed that poor sleep is linked to difficulty in concentrating, having too much energy and being unable to control behaviour – the main traits of attention deficit hyperactivity disorder.
Hopefully, this study could lead to the development of treatments that don’t involve drugs.
Speaking at a pharmacology conference in Paris, Professor Sandra Kooij, from Amsterdam, outlined research which shows poor sleep is a sign that our biological clocks aren’t properly synchronised. This is also the case with ADHD. “Our research is making clear that sleep disruption and ADHD are intertwined,” she said. “Essentially, they are two sides of the same physiological and mental coin.”
Symptoms of ADHD, which also include impulsiveness and mood swings, are generally noticed at school age. It’s thought that between 2% and 5% of people are affected by ADHD at some time in their lives.
In addition, about 80% of cases have profound sleep disturbances, often delays in the onset of sleep. “These people simply cannot go to bed and fall asleep at the end of the day like others,” said Prof Kooij. “And that has consequences. Affected individuals sometimes cannot get to sleep until around 3am but they still have to get up to go to work or school. The result is a drastic loss of sleep.”
This is linked, in turn, to disturbances in levels of dopamine and melatonin in the brain, she added. These chemicals control when we fall asleep and when we wake up through our internal biological clock which keeps us in sync with the 24-hour day.
Other conditions linked to disturbed dopamine and melatonin levels include restless leg syndrome – an irresistible urge to move your legs – and sleep apnoea, where breathing is disturbed during sleep.
These disorders are also linked to ADHD, said Prof Kooij.
Professor Andreas Reif, of University Hospital in Frankfurt, agrees. The crucial point is ADHD appears to be triggered by disruptions to the body clock. Would restoring a patient’s body clock help treat ADHD?
Prof Kooij said her team was now looking for biomarkers, such as vitamin D levels, blood glucose, 24-hour blood pressure and heart-rate that are linked to sleeplessness.
“Once we can do that, we may be able to treat some ADHD by nonpharmacological methods, such as changing light or sleep patterns.