Non-Hodgkin lymphoma risk in adults living with HIV across five continents

OBJECTIVE: To compare non-Hodgkin lymphoma (NHL) incidence rates in adults who started antiretroviral therapy (ART) across the Asia-Pacific, South Africa, Europe, Latin, and North America. METHODS: We included cohort data of adults living with HIV who started ART after 1995 within the framework of the International epidemiology Databases to Evaluate AIDS (IeDEA) and the Collaboration of Observational HIV Epidemiological Research in Europe (COHERE). We used flexible parametric survival models to compare regional NHL rates at 2 years after ART start and to identify risk factors for NHL. RESULTS: We included 210 898 adults with 1.1 million person-years (pys) of follow-up and 1552 incident NHL cases (raw overall incidence rate 142/100 000 pys). After adjusting for age at ART start, first-line ART regimen, calendar period of ART start, and especially current CD4 cell count, NHL rates were similar across regions for most population groups. However, South African women remained at increased risk of developing NHL compared with their European counterparts [adjusted hazard ratio [aHR] 1.79, 95% CI 1.19-2.70]. In Europe, Latin, and North America, NHL risk was highest in MSM (aHR 1.30, 95% CI 1.14-1.48), followed by heterosexual men (referent), and women (aHR 0.66, 95% CI 0.57-0.78). CONCLUSION: The risk of developing NHL is higher in women in South Africa than in Europe and higher in MSM compared with heterosexual men and women. Reasons for these differences remain unclear. Early ART access and regular patient monitoring to avert low CD4 cell counts remain key for NHL prevention.