Incidence of abnormal anal cytology in HIV-infected and HIV-uninfected men who have sex with men

Introduction: Anal cytology is used in the prevention of anal cancer, which disproportionally affects men who have sex with men (MSM). Data on the incidence of cytologic abnormalities in these individuals are scant.

Methods: MSM with baseline negative anal cytology and at least one further adequate cytology were included. Incidence rate for positive atypical squamous cells of undetermined significance (ASC-US+) was calculated. Kaplan-Meier curves were compared by log-rank test according to HIV status, baseline high-risk human papillomavirus (HPV) (high-risk HPV-negative, HPV16-positive, other high-risk HPV-positive [non-HPV16]) and high-risk HPV persistence (positive from baseline to the first ASC-US+ or last visit for those who remained cytologically negative). Cox univariate and multivariate analyses were performed.

Results: A total of 250 MSM were included: 52/153 (34.0%) HIV-uninfected MSM had an ASC-US+ report at follow-up (incidence: 13.1 × 100 person-years; 95% CI, 9.8-17.2); 48/97 (49.5%) HIV-infected MSM developed cytologic abnormalities (incidence: 16.0 × 100 person-years; 95% CI, 11.8-21.2). ASC-US+ incidence in HIV-uninfected and HIV-infected MSM did not differ significantly (p = .32). Kaplan-Meier curves did not differ significantly according to baseline high-risk HPV. Differences were significant between those with and without persistent high-risk HPVs, both among HIV-uninfected (p = .03) and HIV-infected MSM (p = .008). Age (adjusted hazard ratio [aHR], 0.98; 95% CI, 0.96-0.99), high-risk HPV persistence (aHR, 1.57; 95% CI, 1.02-2.39), and condomless receptive anal sex (aHR, 1.99; 95% CI, 1.31-3.03) were predictors for incident ASC-US+.

Conclusions: Despite the limited number of subjects, in our study HIV-uninfected and HIV-infected MSM have a similar ASC-US+ incidence. Occurrence of ASC-US+ was significantly affected by age, high-risk HPV persistence, and condomless receptive anal sex. The assessment of HPV persistence might identify those MSM at higher risk for anal lesions.