Risk and Predictors of Esophageal and Stomach Cancers in HIV-Infected Veterans: A Matched Cohort Study.

Abstract

To evaluate the risks of esophageal and stomach carcinomas in people living with HIV (PLWH) compared with the general population and risk factors for these cancers in PLWH. Retrospective cohort study in the Veterans Health Administration. We compared incidence rates for esophageal and stomach cancers in 44,075 HIV-infected male veterans with those in a matched HIV-uninfected cohort (N = 157,705; 4:1 matched on age and HIV-index date). We used Cox regression models to estimate Hazard ratios (HRs) and 95% confidence intervals (CIs) for associations with HIV infection and for cancer risk factors in PLWH. In unadjusted models, HIV infection was associated with increased risks of esophageal squamous cell carcinoma (ESCC; HR, 2.21; 95% CI: 1.47 to 3.13) and gastric cardia cancer (HR, 1.69; 95% CI: 1.00 to 2.85) but associated with lower risk of esophageal adenocarcinoma (EAC; HR, 0.48; 95% CI: 0.31 to 0.74). After adjusting for age, race/ethnicity, smoking and alcohol use, HIV infection remained statistically significantly associated with elevated risk for ESCC [adjusted hazard ratio (aHR), 1.58; 95% CI: 1.02 to 2.47], especially among HIV-infected patients with CD4 count ≤200 (aHR, 2.20; 95% CI: 1.35 to 3.60). HIV infection was not associated with risks of EAC (aHR, 0.82; 95% CI: 0.53 to 1.26), gastric cardia (aHR, 0.80; 95% CI: 0.33 to 1.94), or noncardia (aHR, 1.06; 95% CI: 0.61 to 1.84) cancers. Risk factors for these cancers in HIV-infected patients were otherwise similar to those in general population (eg, Helicobacter pylori for gastric noncardia cancer). HIV-infected individuals with low CD4 count are at highest risk for ESCC, but HIV infection was not independently associated with EAC or gastric cancer after adjusting for confounders.