Speaking about other possible conditions, anecdotally there are two people in my family who saw a psychiatrist for ADHD like symptoms, who years later were eventually diagnosed with sleep apnea (both with a normal BMI).
It seems like this is not uncommon, quoting Matthew Walker’s “Why We Sleep”:
> Based on recent surveys and clinical evaluations, we estimate that more than 50 percent of all children with an ADHD diagnosis actually have a sleep disorder, yet a small fraction know of their sleep condition and its ramifications.
I have sleep apnea, and ADHD. Before getting on CPAP life was pretty tough. It definitely exacerbated my ADHD at least 2x. So, I can understand that if you're neurotypical and have sleep apnea it is going to be affecting your executive function such that you aren't at 100%. The flip side is ADHDers are significantly more likely to be morbidly obese and have other health complications like sleep apnea as a result. At that point it's a real downward spiral. Very glad I finally sought treatment for my apnea after kicking the can down the road for 4 whole years, which is very typical ADHD behavior in itself.
For real though CPAP is life changing if you need it and you get on it.
It seems like this is not uncommon, quoting Matthew Walker’s “Why We Sleep”:
> Based on recent surveys and clinical evaluations, we estimate that more than 50 percent of all children with an ADHD diagnosis actually have a sleep disorder, yet a small fraction know of their sleep condition and its ramifications.