It's not uncommon for adults with autism to have gone through much of their lives unaware that they have the neurological disorder, according to an expert who says there are few treatments available to adults with autism.

"Not all treatments that are developed for children are appropriate for adults," Dr. Evdokia Anagnostou, a senior clinical scientist at Holland Bloorview Kids Rehabilitation Hospital, told CTV's Canada AM on Thursday.

Anagnostou said the criteria for diagnosing autism was "clarified" in the early 1990s, so many adults who are now in their late 30s and 40s received their diagnoses in adulthood.

She added that those on the on the high-end of the autism spectrum are often misdiagnosed as having depression or anxiety as teens.

"Then they don't get diagnosed (with autism spectrum disorder) until young adulthood," she said.

Anagnostou said there's a clear need for social skills and life skills training that is geared towards adults.

"We have to remember that these people are going to start entering the aging spectrum, and without understanding the biology, we have a little bit of difficulty figuring out what the appropriate treatments would be."

Anagnostou noted that only 15 per cent of adults with autism have "meaningful employment," and the vast majority of those jobs are part-time.

"There is a very active effort to try and identify what it would take to actually utilize this very unique skill-set that adults with autism spectrum disorder have to include them in the workforce," she said.