A lot of people in the comments appear to have a misunderstanding of ADHD and sleep disorders. It is possible to have both conditions simultaneously, and likely very common. ADHD is a condition defined by a sustained period of symptoms, not underlying causes or biological tests. It is 100% consistent for someone to have ADHD in one environment and not in another. This is how it is viewed in psychiatry. If you spend many years as an accountant focusing on detailed work in your job, but you can’t focus to complete your work, you may be diagnosed with ADHD and treated with medicine. If you then change careers to be an artist in a creative field, but face no dysfunction or difficulty in completing your work, you would no longer be diagnosed. The same applies to having a sleep disorder and then getting it treated. Though it is not clear if sleep disorders in childhood cause irreversible changes to the brain.