Parents consulting the Psychology Department of the General Children's Hospital of Penteli about their children's concentrating difficulties often complain that they also present sleep problems, such as nightmares, somnambulism, difficulties to fall asleep etc. The aim of the present study is to examine the co-morbidity between ADHD and sleep disorders, as long as previous studies at our Department

The sample consisted of 173 children, who consulted the Department about the above problems, aged 6 to 14 (68,2% boys, 31,8% girls). Children were categorized into two groups: a) children diagnosed with ADHD b) children not diagnosed with ADHD. Parents were invited to completed the ADHD-IV scale, as well as the Aschenbach CBCL test. Children were submitted to BECK's Youth Inventory. In order to compare the two groups we used the t test.

Considering parents and children's reports, it was found that co-morbidity between ADHD and sleeping difficulties does exist to a significant level. More precisely, children with hyperactivity, compulsiveness and concentrating difficulties also seemed to experience low quality of sleep. Co-morbidity between ADHD and sleep disorders was not found to be affected by sex, whereas age seemed to be an important factor.

A considerable percentage of children with ADHD was also found to present significant sleep disorders. It is also important to note that children presenting not the whole syndrome but some symptoms of ADHD, also tend to have sleep difficulties.