Substance Use Among HIV-Infected Patients Engaged in Primary Care in the United States: Findings From the Centers for AIDS Research Network of Integrated Clinical Systems Cohort

More than 1 million people are currently living with HIV in the United States.1 In multiple studies, including those involving probability samples, high rates of substance use have been observed among HIV-infected individuals.2---7 For example, in a nationally representative sample of 2864 HIV-infected adults, 40% reported having used an illicit drug other than marijuana in the preceding 12 months, and more than 12 % had screened positive for drug dependence.8---10 In another study focusing on a multisite sample of 970 HIV-infected indi-viduals recruited through outreach programs across 8 US cities, 40 % of the respondents reported heavy alcohol use or crack---cocain