consequences of addition in lieu of abstinence (Gerstein and Harwood, 1990).
This approach appears to go hand in hand with the objective of most needle exchange programs: promote harm reduction while trying to encourage program participants to enter treatment. This is reflected by the evidence presented in Chapter 3 showing that some needle exchange programs are a primary source of referrals for treatment. Moreover, injection drug users with no prior treatment history have sought out treatment services as a result of their contact with needle exchange programs (Christensson and Ljungberg, 1991; Heimer et al., 1993). It would appear that needle exchange programs are serving as a bridge to treatment for a subpopulation of injection drug users for whom traditional treatment recruiting efforts have been unsuccessful.
Treatment programs for injection drug use are for the most part methadone maintenance programs. Evaluation of these programs has shown repeatedly that increased social functioning, reduced drug use, and reduced criminal involvement do follow from methadone maintenance treatment—for those who remain in treatment (Ball and Ross, 1991; Gerstein and Harwood, 1990; Hubbard et al., 1989; McLellan et al., 1993). For patients who leave methadone treatment prematurely, not many appear to maintain these gains. In a study that is considered to be one of the most careful examinations of this phenomenon, over 80 percent of patients relapsed to injection drug use within the 12 months subsequent to their leaving treatment prematurely (Ball and Ross, 1991).
Given the chronic nature of the disorder, these relapses are also to be expected of some who are in treatment. This point is reinforced by the published findings of an ongoing longitudinal study of HIV infection and risk behaviors among 152 injection drug users in treatment and 103 out of treatment: the elevated risk of out-of-treatment injection drug users was clearly evident (Metzger et al., 1993). Continued illicit drug use was reported by a substantial portion of in-treatment participants.
These data and the results of other studies have documented significant reductions in HIV drug-use risk behaviors among in-treatment injection drug users (Ball et al., 1988; Cooper, 1989; Longshore et al., 1993; Novick et al., 1990). Moreover, the reported data from the longitudinal study by Metzger et al. (1993) show that injection drug users who are not in methadone treatment were significantly more likely to become infected than comparable individuals who were enrolled in a methadone treatment program. That is, 4 percent of those who remained in treatment for the first 18 months became infected, compared with 22 percent of those who stayed out of treatment. Although selection bias cannot be excluded, it would seem that not only is methadone treatment effective in treating the disorder of drug abuse but it also reduces HIV risk behaviors (i.e., needle use) and, more