Studies have reported young ages at cancer diagnosis in HIV-infected people, suggesting that HIV accelerates carcinogenesis. However, these comparisons did not account for differences in population age structures.
To compare ages at diagnosis for non-AIDS-defining cancers arising in the AIDS and general populations, after adjusting for differences between these populations in age and other demographic characteristics.
Registry linkage study
15 U.S. HIV/AIDS and cancer registry databases.
People with AIDS in the HIV/AIDS Cancer Match Study (N=212,055, 1996–2007).
We compared the age-at-diagnosis distributions of cancers in the AIDS and general populations, after adjusting for age and other demographics.
The proportion of person-time contributed by older persons (65+ years) was far smaller in the AIDS (1.5%) than the general population (12.5%). Reflecting this difference, the ages at diagnosis for most cancers were ~20 years younger among people with AIDS. However, after adjustment for differences in the populations at risk, the ages at diagnosis in the AIDS and general populations did not differ for most cancers (e.g., no difference in the median ages of colon, prostate or breast cancers; all p>0.1). In contrast, ages at lung (median 50 vs. 54 years) and anal cancer (42 vs. 45 years) were significantly younger in people with AIDS than expected in the general population (p<0.001), and the age at Hodgkin lymphoma was significantly older (42 vs. 40 years, p<0.001).
We lacked information on other cancer risk factors, including cigarette smoking. Further, our analysis was restricted to non-Hispanic whites and non-Hispanic blacks who had AIDS, perhaps limiting the generalizability of our findings to other racial and ethnic groups and to people with HIV, but without AIDS.
For most cancers, the age of diagnosis is similar in the AIDS and general populations, after accounting for the ages of the populations at risk. Modest age differences remained for a few cancers, perhaps reflecting acceleration of carcinogenesis by HIV or earlier exposure to cancer risk factors.