June 28, 2007
New admissions were recruited at drug abuse treatment programs (2000-2004), and drug users from the community were recruited using respondent-driven sampling (2004). In each study, both injecting and non-injecting drug users were included. "Former injectors" were defined as people who had used heroin and/or cocaine in the six months prior to the interview and who had injected illicit drugs in the past, but whose most recent injection was six or more months prior to the study interview. "Current" injectors were defined as people who had injected heroin and/or cocaine in the six months before the interview.
A structured interview on drug use history was administered, and a serum sample was taken and tested for HIV.
For the drug abuse treatment program study, 104 former injectors were recruited, and 229 current injectors were recruited for the community recruitment study; 160 former injectors and 1,731 current injectors were recruited from the drug abuse treatment study.
Compared with current injectors, former injectors were older and more likely to be African American. Former injectors reported long intervals since their most recent injection, a mean of 8 and 12 years in the drug abuse treatment program study and the community recruitment study, respectively. Concerns about health, social stigmatization and self-image, and preference for intranasal drug use were among the most common reasons for stopping injection. The results were highly consistent across the two studies.
The authors concluded that the "transition from injection to non-injection use appears to be a relatively stable behavior change for many former injectors, who report a decade or more without injecting. Developing a greater understanding of the transition from injection to stable non-injection drug use may provide insights into the natural histories of drug use and addiction," they noted.