Risks of Opportunistic Infections in People with Human Immunodeficiency Virus with Cancers Treated with Chemotherapy

Background: We ascertained incidence of opportunistic infections (OIs) in people with human immunodeficiency virus (PWH) with cancer undergoing chemotherapy with non-human immunodeficiency virus (HIV) comparators. Methods: We identified 2106 PWH and 2981 uninfected Veterans with cancer who received at least 1 dose of chemotherapy between 1996 and 2017 from the Veterans Aging Cohort Study. We ascertained incident OIs within 6 months of chemotherapy amongst zoster, cytomegalovirus, tuberculosis, Candida esophagitis, Pneumocystis jirovecii pneumonia (PCP), toxoplasmosis, Cryptococcosis, atypical Mycobacterium infection, Salmonella bacteremia, histoplasmosis, coccidioidomycosis, or progressive multifocal leukoencephalopathy. We used Poisson methods to calculate OI incidence rates by HIV status, stratifying for hematological and nonhematological tumors. We compared OI rates by HIV status, using inverse probability weights of HIV status, further adjusting for PCP prophylaxis. Results: We confirmed 106 OIs in 101 persons. Adjusted OI incidence rate ratios (IRRs) indicated higher risk in PWH for all cancers (IRR, 4.8; 95% confidence interval [CI], 2.8-8.2), hematological cancers (IRR, 8.2; 95% CI, 2.4-27.3), and nonhematological cancers (IRR, 3.9; 95% CI, 2.1-7.2). Incidence rate ratios were not significantly higher in those with CD4 >200 cells/mm3 and viral load <500 copies/mL (IRR, 1.8; 95% CI, 0.9-3.2). All PCP cases (n=11) occurred in PWH, with 2 microbiologically unconfirmed cases among 1467 PWH with nonhematological cancers, no PCP prophylaxis, and CD4 counts >200/mm3. Conclusions: Veterans with HIV undergoing chemotherapy had higher rates of OIs than uninfected Veterans, particularly those with hematological cancers, but not in PWH with HIV controlled disease. Our study does not support systematic PCP prophylaxis in solid tumors in PWH with HIV controlled disease.