Yes, I diagnosed at 30. Ever since finding out that I am something that I loathe, I decided to be done with people. I know exactly why people treated me and thought of me as mentally challenged (aka retarded). I am one who can not mask for the life of me, thus I have an outward appearance as if I'm retarded. In turn makes people think I'm literally retarded. My speech also sounds like I have Down syndrome. If you ever interacted with a person with ASD that can not mask and talks like a retard. You probably thought this person is a retard, you probably felt a very strong urge to not interact with this individual ever again at any cost. That is what happens to me whenever I interact with a Special needs individual that is clearly 'special'. And I do have a strong hatred towards stupid people, retards are one of them. In fact that is why I don't talk to my mom that much.
The only "good" thing about my case is my above average intelligence at 116. I'm one those people who believe that if you're average or below intelligence, you deserve the label of stupid. Guess what, due to abuse and mental illness. My IQ is now 94, I'm STUPID these days. When I found that out, I almost had a panic attack. My photographic or near photographic memory is reduce to a very insufficient memory. I never knew autistic brains can decline so much as my brain has. I'm in my 30's, I was expecting this kind of decline would start when I hit 60. I'll ctb before then if the declination continues.
I also saw a report that abuse can cause the memory to degrade.