Crack cocaine: a five-year follow-up study of treated patients

To follow-up a group of 131 crack cocaine users and examine drug use, treatment experience, employment status, involvement in crime and mortality at 2 and 5 years.

Consecutive crack-dependent patients who were admitted to a detoxification unit in São Paulo between 1992 and 1994 were re-interviewed on two occasions: 1995-1996 and 1998-1999.

5 years after treatment information was obtained on 124 (95%) of the original cohort. 39.7% (n = 52) of the patients reported having been abstinent from cocaine for at least the last year, and 21.4% (n = 28) had used the drug. Of those subjects not using cocaine at 2 years, 19 (62%) were still abstinent at 5 years. Twenty-three (17.6%) patients had died by the 5-year follow-up with homicide, due to firearms or other weapons, being the commonest cause (n = 13). The annual adjusted mortality rate for the sample was 24.92 deaths/1,000 individuals, the excess mortality rate was of 21.64 deaths/1,000 individuals, and the standardized mortality ratio was 7.60. A history of injecting drug use, unemployment at the time of the index admission and administrative discharge at the index admission were factors that contributed to the risk of dying over the next 5 years.

There was a progressive movement towards abstinence over the follow-up period, and there was evidence that once abstinence had been achieved it was maintained. On the other hand, the mortality rate was extremely high and was higher among those who were still using crack at 2 years.