lack of regular circadian sleep may be behind attention deficit hyperactivity disorder (ADHD), which affects around 75% of children and adults, according to a new study.
ADHD, which is associated with many sleep-related disorders, including restless-leg syndrome, sleep apnea, circadian rhythm disturbance and delayed sleep phase syndrome, was until now thought to be a separate issue. According to the findings proposed at the 30th ECNP Congress in Paris, the association is because the day and night rhythm is disturbed, the timing of several physical processes is disturbed, not only of sleep, but also of temperature, movement, meals times.
In 75% of ADHD patients, the physiological sleep phase – where people show the physiological signs associated with sleep such as changes in the level of the sleep hormone melatonin and changes in sleep-related movement is delayed by 1.5 hours.
“Many sufferers benefit from taking melatonin in the evening or bright light therapy in the morning, which can help reset the circadian rhythm," Sandra Kooij, associate professor at VU University Medical Centre in Netherlands, said.