[Prevalence of infection by the human immunodeficiency virus type 1 in drug addicts in Madrid, over a 5 year period].

BACKGROUND: Firstly, to evaluate the annual levels of seroprevalence of antibodies against the type I human immunodeficiency virus in a sample of 1,232 intravenous drug users (IVDU) admitted for treatment to a hospital detoxication unit i Madrid over a period of 5 years. Secondly, attempt to distinguish the existence of variable which differentiate seropositive and seronegative IVDU.

METHODS: Data concerning sociodemographic profile and history of addiction were collected. The detection of antibodies vs HIV was carried out by the enzyme immunoanalysis technique which was confirmed by indirect immunofluorescence methods and western blot if positive.

RESULTS: There was a diminution in the levels of seropositivity during the 5 years evaluated (74%, 65%, 66%, 62% and 59%, p less than 0.05) with the infection by the HIV being more frequent in those addicted for a longer period of time, with more attempts at treatment, who had initiated drug dependence at an earlier age, had been in prison, and who, apart from heroin, also consumed benzodiacepins++ and/or alcohol.

CONCLUSIONS: A decrease in the levels of annual seroprevalence of HIV anti antibodies was found and the group of seropositive IVDU presents particular characteristics emphasizing the need for promoting treatment programs with adequate retention capacity for drug users.