Clinical characteristics, incidence, and risk factors of HIV-related Hodgkin lymphoma in the era of combination antiretroviral therapy.

HIV-infected patients are at increased risk for developing HIV-related Hodgkin lymphoma (HIV-HL) despite the success of combination antiretroviral therapy (cART). To study the incidence of HIV-HL in HIV-patients with respect to the general population of Brescia, Italy, we conducted a single-center cohort study of HIV-patients followed from 1999 to 2009. The incidence of HIV-HL was compared to the incidence in the general population of Brescia using standardized incidence ratios (SIRs). Poisson analysis was used to study the association between covariates and HL. A total of 5085 HIV-patients were observed among 30,946 person-years; 30 patients developed HIV-HL. The incidence rate was 9.9 (95% confidence interval [CI], 6.7-14.1) per 10,000 person-years of follow-up. HL was substantially more frequent in HIV-patients than in the general population living in the same district area [standardized incidence rate, SIR=21.8 (95% CI, 15.33-31)]. The risk of HIV-HL tended to increase with lowering CD4+ cell counts at time of HL diagnosis [adjusted incidence relative risk (IRR) for CD4 cell count<50 cells/μL: 41.70, p<0.001]. HL risk had been elevated during the 6 months after combination antiretroviral therapy (cART) initiation (IRR: 26.65, p<0.001). Twenty-two HIV-HL cases were matched to 3280 controls. In the year preceding HIV-HL diagnosis the mean change in CD4+ cell counts between cases and controls was significantly different (-99 cells/μL for cases vs. +37 cells/μL for controls, p<0.0001). Compared with the general population, HIV-infected patients showed an increased risk for developing HL. The risk of HIV-HL increased significantly in the first months after cART initiation.