Low-Level HIV Viremia: Risk Factor for Non-Hodgkin Lymphoma

July 5, 2014

Antiretroviral therapy has greatly reduced the incidence of non-Hodgkin lymphoma. But, a new study finds the risk is still high even at low levels of HIV infection.

The incidence of non-Hodgkin lymphoma, one of the AIDS-defining conditions,1 has decreased since the advent of antiretroviral therapy (ART). The risk of non-Hodgkin lymphoma, however, continues to be higher by several-fold in HIV-infected patients-even those receiving ART-compared with non–HIV-infected patients.

Several risk factors have been associated with this increased risk in the HIV-infected population.2 A recent study published in the journal Clinical Infectious Diseases examined the relationship between HIV viremia, which is a modifiable risk factor, and the risk of the development of non-Hodgkin lymphoma.3 The researchers followed the incidence of non-Hodgkin lymphoma in HIV-infected patients who started combination ART (cART) and in whom HIV viral load was suppressed. Patients were registered with the Centers for AIDS Research Network of Integrated Clinical Systems.

The researchers identified 37 new non-Hodgkin lymphoma diagnoses in 21,607 person-years of follow-up. The most common non-Hodgkin lymphomas were diffuse large B cell lymphoma in 57% of cases; primary CNS lymphomas in 19% of cases; and Burkitt lymphoma in 11% of cases. The authors reported a correlation between HIV viremia and the incidence of non-Hodgkin lymphoma. Patients with viral loads of 51 to 500 copies/mL had a higher hazard ratio of developing non-Hodgkin lymphoma compared with patients with ≤50 copies/mL (HR current = 1.66 [95% CI, 0.70-3.94]; HR 3-month lagged = 2.10 [95% CI, 0.84-5.22]; and HR 6-month lagged = 1.46[ 95% CI, 0.60-3.60]).4

The study’s findings are important because they show that continued HIV replication even at low levels increases the risk of non-Hodgkin lymphoma. The study also highlights the effectiveness of achieving a profound and sustained HIV suppression with ART. Primary care physicians treating HIV-infected patients should be cognizant of the increased risk of non-Hodgkin lymphoma in this population.3

References:

1. Centers for Disease Control and Prevention. 1993 revised classification system for HIV infection and expanded surveillance case definition for AIDS among adolescents and adults. MMWR Recomm Rep. 1992;41:1-19.

2. Silverberg MJ, Chao C, Leyden WA, et al. HIV infection, immunodeficiency, viral replication and the risk of cancer. Cancer Epidemiol Biomarkers Prev. 2011;20:2551-2559.

3. Achenbbach CJ, Buchanan AL, Cole ER, et al; Centers for AIDS Research (CFAR) Network of Integrated Clinical Systems (CNICS). HIV viremia and incidence of non-Hodgkin lymphoma in patients successfully treated with antiretroviral therapy. Clin Infect Dis. 2014 Feb 12. [Epub ahead of print]