To the Editor.—
Kaslow et al1 found that psychoactive substance use did not accelerate the progression toward acquired immunodeficiency syndrome (AIDS) in a large cohort of homosexual men. However, as reported by the authors, the numbers of intravenous drug and opiate users were small.In previous studies, frequent drug injection was found to be associated with T4-cell loss.2 However, the relationship between continued drug injection and incidence of AIDS in infected subjects remains unclear. We are conducting a cohort study to estimate the risk of developing AIDS in human immunodeficiency virus seroconverters who are intravenous drug users (IVDUs).3 Most of them admitted to continued drug injection, mainly heroin injection, after human immunodeficiency virus seroconversion. To study the role played by drug injection in the progression of human immunodeficiency virus infection, we compared the incidence of AIDS in 261 seropositive IVDUs to that in 89 non—drug-injecting homosexual men.