SHARING OF INJECTION EQUIPMENT AMONG 3755 INTRAVENOUS-DRUG-USERS IN VALENCIA, SPAIN, 1987-1992

Background. In order to identify, in a sample of heroin intravenous dr ug users (IVDU), those factors associated with the predominant risk be haviour related to the transmission of HIV-1 infection-sharing of inje ction equipment-a cross-sectional survey was carried out in Valencia, Spain from 1987 to 1992. Methods. Informed consent and pertinent data were obtained from 3755 heroin IVDU recruited at two public AIDS Infor mation Centres in two cities in the region of Valencia. Data were gath ered on sociodemographic variables, and sexual and drug use behaviour by interview. The subjects were subsequently tested for HIV-I antibody . A univariate analysis was carried out to identify variables that wer e significantly associated with sharing injection equipment. A logisti c regression model was used to control for possible confounders. Resul ts. The IVDU who were teenagers, prostitutes (OR = 1.95), who had anti bodies to HIV-1 (OR = 1.30) or who had an IVDU steady partner were at significantly higher risk for sharing of injection equipment. Higher l evels of education, condom use (OR = 0.65) and living in the smaller c ity (OR = 0.75) were inversely related to sharing injection equipment. Conclusions. Our results suggest that different subgroups of IVDU hav e different characteristics that place them at different risk for HIV- I infection. These characteristics should guide the design and intensi ty of specific preventive interventions. Teenagers and IVDU with low e ducational levels should be targetted for special attention by health authorities.