froggy Yes
I am a Viet Nam vet and found out I had PTSD in 1980. I was in Viet Nam from 1968 to 1969. I worked at a Vet Center, I am a licensed clinical social worker, and one of the counselors was working with a World War II bomber pilot who and just retired and all his symptoms became full blown in 1987 or so. I had symptoms of depression, night mares, and intermitten rage, but did not have the full blown symptoms until 1980 when I could not get Viet Nam out of my head. It is not uncommon.