Other than human papilloma virus (HPV) type 16, the incidence of high-risk anal HPV was higher among gay and bisexual men (GBM) with HIV, according to a results published in The Journal of Infectious Diseases.
Investigators gathered data from the Study of the Prevention of Anal Cancer, a 3-year project collecting data on Australian GBM aged 35 and older, including incidence, clearance, and risk factors for 13 high-risk HPV (HRHPV) types at baseline and during 3 consecutive annual visits.
Of the 617 men included, 397 (64.3%) were HIV-negative and 220 (35.7%) were HIV-positive. A majority (95.3%) of patients identified as gay or homosexual. HIV-positive men reported significantly more lifetime sexual partners (P <.001) and were more likely to report no partners in the past six months (P <.001).
In total, 525 participants (85.1%) were included in the HRHPV analysis. Of these, 348 (66.3%) acquired at least 1 HRHPV infection during the study. Incidence of the 12 non-16 HRHPV was 3.92 per 100 person-years (PY). The incidence of HPV16 was 4.44 per 100 PY and 4.33 per 100 PY (P =.916) in men without and with HIV, respectively. High-risk non-HVP16 incidence was 36.54 per 100 PY and 51.80 per 100 PY in men without and with HIV, respectively (P <.001).
The annual clearance rate for HPV16 was 13.21 per 100 PY. There was no significant difference in HPV16 clearance by HIV status (P =.739). Clearance of non-HPV16 types was higher than HPV16 types (P <.001). While clearance rates were not associated with HIV overall, clearance rates were significantly lower for both HPV16 (P =.015) and the other HRHPV types (P =.007) in patients with HIV who had a lower nadir CD4 (less than 200 cells/μL).
According to investigators, the analysis of the impact of immune control on anal HRHPV was limited by the low numbers of HPV16. This led to a substantial lack of statistical power for concurrent CD4.
“The higher incidence of non-16 HRHPV types, coupled with the lower clearance of non-16 HRHPV types in those with past impaired immune function, is consistent with the greater role of non-16 HRHPV in anal cancer in HIV-positive people,” the study authors concluded. However, because HIV treatment is now initiated immediately or shortly after diagnosis, nadir CD4 counts are more likely to be normal in HIV-positive people in the coming years. Therefore, study authors believe the impact of impaired immunity on clearance non-HPV16 types may also wane over time and early HIV treatment should reduce the role of high-risk non-HPV16 types in anal cancer and lower the incidence of this cancer in HIV-positive men.
Disclosures: Several authors report grant funding from several pharmaceutical companies. Please see the original reference for full disclosure details.
Poynten IM, Jin F, Garland SM, et al. HIV, immune dysfunction and the natural history of anal high-risk human papillomavirus infection in gay and bisexual men. J Infect Dis. Published online November 21, 2020. doi:10.1093/infdis/jiaa723.