Non-fatal injuries and the use of psychoactive drugs among young adults in Spain

We compared the prevalence of injuries requiring medical treatment in the general population, in cocaine users and in heroin users, and we studied the factors associated with the occurrence of injuries in these groups, using data from two interview surveys carried out in 1993 in Spain: the National Health Interview Survey, a national representative sample of the non-institutionalized general population, and a survey of a non-probability sample of heroin or cocaine users selected from the community. The subjects included in the study were persons 16-40 years of age in urban areas: 4261 persons from the general population, 369 cocaine users and 215 heroin users. The annual prevalence of injuries requiring medical treatment was 7.9% in the general population, 10.8% in cocaine users and 35.2% in heroin users. There was a statistically significant positive association of injury occurrence (1) among the general population: with male sex, alcohol use, use of tranquillizers/sleeping pills, and the use of antidepressants or stimulants; (2) in cocaine users: with the use of opiates other than heroin; and (3) in heroin users: with alcohol use, the use of tranquillizers/sleeping pills, and the injected route. The only statistically significant negative association was with the amount of cocaine consumed among heroin users. The results suggest that other psychoactive substances besides alcohol are positively associated with injury occurrence, and that cocaine use may contribute to a reduced risk of injuries associated with the use of depressants (alcohol, tranquillizers, heroin).