Russell Barkley, Ph.D., is considered by many professionals to be the most authoritative expert (researcher), on the cognitive/behavioral aspects of ADHD.

Russell Barkley, Ph.D., is considered by many professionals to be the most authoritative expert (researcher), on the cognitive/behavioral aspects of ADHD.
In his book, Adult ADHD (2010), he details a study where he followed a group of non-ADHD young kids to age 30 and compared them to a group of ADHD kids. There were about 100 kids in each group.
The most striking finding in this study is that untreated ADHD impairs functioning in every area of life. They are less likely to be employed, and if employed, make less money, have had more jobs, have less education, worse grades, or took longer to get through school. They were also in greater debt, had more relationship problems, worse health, more traffic tickets, and other legal problems.
In my clinical experience over the past 40 years I have seen more people’s lives dramatically improve with ADHD treatment than any other mental health condition I treat, usually by prescribing a stimulant.
Long-term adherence to treatment is a problem with all medical and mental health problems, but many times it is because patients did not get the right medication(s) at the right dose(s). Sometimes cost is the primary problem but adequate generic medications and sometimes patient assistance programs can solve that issue.
We ADHD personalities are driven by interest rather than importance. We tend to be easily distracted and have way too many things on our mind at any given moment. ADHD medications can help us be calm and focused, and not only cope with our rapidly changing modern world, but actually thrive.