Epidemiological surveillance of opioid-related episodes in an emergency room of Barcelona, Spain (1979-1989)

In the early 80's opioid addiction was a low prevalence problem in Spain, grew enormously during that decade and became the most important risk factor for AIDS in recent years. The limitations of assessing the prevalence of illegal drug use by means of standard epidemiological methods lead, worldwide, to the use of indirect indicators. A Register of Toxicological Emergencies, developed for research purposes and containing data from 1979 to 1989 at the Hospital del Mar (Barcelona) is described. Results for opioid-related emergencies are presented, showing an epidemic increase in the number of such emergencies after 1981. The total number of opioid-related emergencies was 18,042 with a mean of 2.23 opioid-related emergency admissions per client throughout the whole period, implying that some 8000 persons were seen. In episodes from non-arrestees, mean age increased slightly over time, the male/female ratio being 2.5; withdrawal was the more frequent reason for attendance (53%), overdose accounting for 9% of admissions, and other medical conditions for 33%. Non-arrested women were more likely to attend for other medical conditions and overdoses than men. The importance of this kind of register as well as its limitations for assessing the trend of opioid use prevalence is discussed.