In a study reviewed in May 2009 on the Psychcentral.org site, a diagnosis of ADHD in childhood was linked with sleep problems in teenagers. This was found to be true even if the teens were not currently showing symptoms of ADHD. The sleep problems found included insomnia, sleep terrors, nightmares, teeth grinding and snoring.
As a parent, this is something to watch for if your teenager was ever diagnosed with ADHD. The study found some overlap between the two conditions, meaning that in some cases, the sleep problems were the primarly problem and were making behavioral problems worse. In other cases, the sleep problems were thought to be caused by situations related to the ADHD. These included medications, hyperactivity itself, and in some cases, internet addiction (which can be a form of self-medication).
Take a look at the study review and let us know what you think.