CHANGES IN NETWORK CHARACTERISTICS AND HIV RISK BEHAVIOR AMONG INJECTION-DRUG USERS

Studies indicate that HIV risk behaviors vary greatly among injection drug users (IDUs). The source of such variation is often ascribed to i ndividual differences, but much of it is due to how IDUs are grouped i nto social networks. Nevertheless, given the turbulent and uncertain l ives red by many IDUs, it would not be surprising if their social netw orks changed substantially over time. We used data from a study of the social networks of IDUs in Chicago and Washington, DC, to examine cha nges in individual behavior and network characteristics over time; The results indicated few changes in standard network measures, such as d ensity of ties or network size, over time. However, specific network c hange measures, that is, indicators of movement into and out of networ ks, showed significant movement of network members over time. Moreover , movement of members into a network significantly predicted a higher likelihood of risky injection drug use over time. We suggest that thes e movements are indicative of a lack of a stable resource base among I DU networks. (C) 1997 Elsevier Science Ireland Ltd.