Duration of Time CD4/CD8 Ratio is Below 0.5 is Associated with Progression to Anal Cancer in Patients with HIV and High-Grade Dysplasia

Background: A CD4/CD8 ratio < 0.5 is associated with increased risk of advanced anal disease (AAD) but it is unknown if duration below 0.5 matters. The purpose of this study was to determine if duration of a CD4/CD8 ratio < 0.5 is associated with increased risk of invasive anal cancer (IC) in people living with HIV and high-grade dysplasia (HSIL). Methods: This single institution, retrospective study used the University of Wisconsin Hospital and Clinics Anal Dysplasia and Anal Cancer Database. Patients with IC versus HSIL alone were compared. Independent variables were mean and percentage of time the CD4/CD8 ratio was < 0.5. Multivariate logistic regression was performed to estimate the adjusted odds of anal cancer. Results: We identified 107 patients with HIV infection and AAD (87 with HSIL, 20 with IC). A history of smoking was significantly associated with the development of IC (95% in patients with IC vs. 64% in patients with HSIL; p = 0.015). Mean time the CD4/CD8 ratio was < 0.5 was significantly longer in patients with IC compared with patients with HSIL (7.7 years vs. 3.8 years; p = 0.002). Similarly, the mean percentage of time the CD4/CD8 ratio was < 0.5 was higher in those with IC versus those with HSIL (80% vs. 55%; p = 0.009). On multivariate analysis, duration CD4/CD8 ratio was < 0.5 was associated with increased odds of developing IC (odds ratio 1.25, 95% confidence interval 1.02–1.53; p = 0.034). Conclusions: In this retrospective, single-institution study of a cohort of people living with HIV and HSIL, increasing duration the CD4/CD8 ratio was < 0.5 was associated with increased odds of developing IC. Monitoring the number of years the CD4/CD8 ratio is < 0.5 could inform decision making in patients with HIV infection and HSIL.