Background: To determine whether demographic and behavioral factors affectimmunoglobulin regulation in HIV infection, we studied injection drug users, women, and minority ethnicand racial groups with and without HIV infection. Material/Methods: A prospective cross-sectional studyof ambulatory persons with or at risk for HIV infection was conducted. We enrolled 48 injection drugusers (IDUs) and 43 non-IDUs seropositive for HIV and 22 seronegative at-risk individuals in the Bronx,New York City. Sixteen HIV-seronegative, non-IDUs controls were also studied. Total serum immunoglobulinlevels, IgG subclasses and lymphocyte phenotypes were measured. Results: Serum IgG, IgA, IgG[sub]1[/sub] and IgG(3)were increased in all stages of HIV infection controlling for injection drug use, gender, race and age(p0.05). Serum IgM levels were significantly decreased in HIV seropositives compared to HIV seronegatives(p

Keywords: Behavior, Ethnic Groups, HIV Infections - immunology, Immunoglobulin G - blood, Immunoglobulins - blood, Regression Analysis, Sex Factors, Substance Abuse, Intravenous - immunology