Low CD4/CD8 ratio predicts cancer risk among adults with HIV

Background Independent of CD4 cell count, low CD4/CD8 ratio in people with HIV (PWH) is associated with deleterious immune senescence, activation, and inflammation, which may contribute to carcinogenesis and excess cancer risk. We examined whether low CD4/CD8 ratios predicted cancer among PWH in the USA and Canada. Methods We examined all cancer-free PWH with one or more CD4/CD8 values from NA-ACCORD observational cohorts with validated cancer diagnoses between 1998-2016. We evaluated the association between time-lagged CD4/CD8 ratio and risk of specific cancers in multivariable, time-updated Cox proportional hazard models using restricted cubic spines. Models were adjusted for age, sex, race/ethnicity, hepatitis C virus, and time-updated CD4 cell count, HIV RNA, and history of AIDS-defining illness. Results Among 83,893 PWH, there were 5,628 incident cancers, including lung cancer (n=755), Kaposi sarcoma (KS, n=501), non-Hodgkin lymphoma (NHL, n=497), and anal cancer (n=439). Median age at cohort entry was 43 years, 87% were male, and 43% were white. Overall median six-month lagged CD4/CD8 ratio was 0.52 (interquartile range: 0.30-0.82). Compared with six-month lagged CD4/CD8=0.80, CD4/CD8=0.30 was associated with increased risk of any incident cancer (adjusted hazard ratio = 1.24 [95% confidence interval: 1.14-1.35]). CD4/CD8 ratio was also inversely associated with NHL, KS, lung cancer, anal cancer, and colorectal cancer in adjusted analyses (all p <0.05). Results were similar using 12-, 18-, and 24-month lagged CD4/CD8 values. Conclusions Low CD4/CD8 ratio up to 24 months prior to cancer diagnosis was independently associated with increased cancer risk in PWH and may serve as a clinical biomarker.