My doc just started asking me questions and was quick to diagnose, but I agree with him that I have a "pure" form of Inattentive ADD and no other conditions. If ADD (or any other condition I imagine) is left untreated it can lead/cause other conditions. It took me from 9 to just two weeks ago at 34 to finally tell someone that I think something is wrong with me and I'm glad I did. My doc is glad I came in so early in life.