What Dr. Cameron appears to be saying is that homosexuals, male or female, die around age 60.
The title of his article in the referred scientific journal Psychological Reports is: Gay obituaries closely track officially reported deaths from AIDS. What that tells me is homosexuals die about the same age as anybody with AIDS.
The second sentence in the article says: This study provides additional evidence that the practice of homosexuality, with its attendant lifestyle, shortens the life of practitioners by about 20 years.. That doesn't say anything about AIDS.
My thought on that is that the gay obituaries are going to be heavily weighted by deaths from AIDs. We're still just looking at an average. It still doesn't tell us much about life expectancy of gay men who do not have AIDS.
The second sentence in the article says: This study provides additional evidence that the practice of homosexuality, with its attendant lifestyle, shortens the life of practitioners by about 20 years.. That doesn't say anything about AIDS.
Gay men, as a group, most certainly have a shorter average lifespan than the general population. However, this average is heavily influenced by the preponderance of AIDS among gay men.
This is analogous to how we measure average lifespan in the population as a whole. The average is actually a bit shorter than how long people can expect to live in actuality because of the statistical effect of infant mortality. Every kid who dies before age one throws the average off.