Prevalence Of High-Grade Anal Dysplasia And Anal Cancer In Veterans Living With Hiv And Cd4/Cd8 Ratio As A Marker For Increased Risk A Regional Retrospective Cohort Study

BACKGROUND: The Department of Veterans Affairs cares for the largest population of patients with HIV of any healthcare system in the United States. Screening for anal dysplasia/cancer is recommended for all veterans with HIV. Exams are invasive, burdensome, and resource intensive. We currently lack markers of disease to tailor screening.OBJECTIVE: The purpose of this study was to establish the prevalence of advanced anal disease (high-grade dysplasia and anal cancer) and to determine whether CD4/CD8 ratio correlates with risk.DESIGN: This was a retrospective regional cohort study of veterans with HIV.SETTINGS: The study was conducted at eight medical centers between 2001 and 2019.PATIENTS: Patients with advanced disease were compared with patients with nonadvanced anal pathology.MAIN OUTCOME MEASURES: Logistic regression modeling was used to estimate adjusted odds of disease as a function of CD4/CD8. Lowest (nadir) CD4/CD8 and nearest CD4/CD8 ratio in each cohort were evaluated.RESULTS: A total of 2267 veterans were included. Fifteen percent had anal pathology (112 with advanced disease (37 cancer and 75 high-grade), 222 with nonadvanced disease). Nadir and nearest ratio were lower in patients with advanced disease versus nonadvanced (0.24 vs 0.45 (p < 0.001) and 0.50 vs 0.88 (p < 0.001)). In adjusted models, a 1-unit increase in nadir or nearest ratio conferred decreased risk of advanced disease (OR = 0.19 (95% CI, 0.07-0.53); p < 0.001; OR = 0.22 (95% CI, 0.12-0.43); p < 0.001). Using a minimum sensitivity analysis, a cutoff nadir ratio of 0.42 or nearest ratio of 0.76 could be used to risk stratify.LIMITATIONS: This was a retrospective analysis with a low screening rate.CONCLUSIONS: In a regional cohort of veterans with HIV, 15% were formally assessed for anal dysplasia. Advanced anal disease was present in 33% of those screened, 5% of the HIV-positive population. A strong predictor of advanced disease in this cohort is the CD4/CD8 ratio, which is a promising marker to stratify screening practices. Risk stratification using CD4/CD8 has the potential to decrease burdensome invasive examinations for low-risk patients and to intensify examinations for those at high risk.