Frequently, life expectancy doesn't mean much to individual people.
Just because, say, people with autism are only expected to live to age 39, doesn't mean that I will die at age 39. I'm 55, and I'm still going strong!
It is often stated that the life expectancy of the average English person was about 19 years in the 18th century. This does not mean that the average person in those days died when they were 19 years old. It just means there was lots of infant mortality then. People definitely lived shorter lives in those days--but many people lived to their 80's and 90's, even back then.
So, James, if you don't smoke, and you don't drink, you'll probably live longer than somebody who smokes and drinks.
Asperger's (and uncomplicated autism), in and of itself, doesn't reduce life expectancy.
If one has autism accompanied by epilepsy, it MIGHT reduce life expectancy.
If one has Down Syndrome, life expectancy is reduced--but is rising every day.
In conclusion, James, you will probably live past age 39 (unlike Jack Benny!)