[Mortality among drug addicts: an Italian multicenter study. ESEDA group (Epidemiological Studies on Effects of Drug...

To investigate temporal and geographical differences in mortality of intravenous drug users (IDUs) in Italy, a multicenter cohort of IDUs entering public treatment centres in Turin (n = 6975), Rome (n = 4660), Naples (n = 3785) and Cagliari (n = 1630) between 1980-1992, was enrolled and followed up till the end of 1992. High mortality rates for all causes, ranging between 20.5/1000 person-years in Rome and 11.0/1000 in Naples, were observed especially in the last two years of the follow-up except in Naples where the mortality reached a maximum in 1983-84. The major causes of death were overdose, AIDS and violence but with some differences among centres. In all cities, the observed mortality among drug injectors was greater than that of the general population; SMRs for all causes were 15.1 (CL = 13.9-16.4) in Turin, 15.6 (CL = 14.4-16.8) in Rome, 8.2 (CL = 7.1-9.5) in Naples and 11.9 (LC = 10.2-13.7) in Cagliari. Different selection criteria for entering treatment throughout centres, and the heterogeneity of the therapeutic programmes offered can be considered to explain the differences of mortality observed among drug users. With regard to the heterogeneity in overdose mortality, the geographical and temporal variations in illegal drugs market should be taken into account. Further investigations are needed to verify these hypotheses.