Recreational amphetamine use and risk of HIV-related non-Hodgkin lymphoma.

The results of many laboratory studies suggest that amphetamine use may lead to altered immune function and cytokine expression, both of which are implicated in HIV-related lymphomagenesis. We examined the hypothesis that use of amphetamines modifies risk of non-Hodgkin lymphoma (NHL) in HIV-infected men in the Multicenter AIDS Cohort Study. Data on amphetamine use were collected every six months during the follow-up period between 1984 and 2002. A total of 171 NHL cases were diagnosed from the 19,250 person-years accrued. Multivariable Cox models were used to estimate the effects of baseline exposures, time-varying recent exposures, and three years lagged exposures on risk of NHL adjusting for potential confounders such as demographics, use of other substances, and risky sexual behaviors. We found that weekly or more frequent use of amphetamines was associated with an increased risk of NHL, with hazard ratios of 1.75 (95% CI = 0.81-3.77) for use at baseline, 4.73 (1.41-15.81) for recent use, and 3.05 (1.19-7.82) for three years prior use. Similar associations were observed when we separately examined systemic NHL and diffuse large B-cell lymphoma. Given these observations, the impact of amphetamines on lymphomagenesis among HIV-infected populations should be assessed more thoroughly.