Predictive Value of Regular Cocaine Use Among Opioid-dependent Patients for Long-term Outcome

Abstract

Objectives: Owing to the limited knowledge of the effect of cocaine use on the outcome of opioid dependence, a long-term follow-up study was conducted to assess the importance of cocaine use in the long-term course. Methods: A representative sample of 350 opioid-dependent patients in treatment was studied over a 4-year period using the European version of the Addiction Severity Index. The sample was split into 2 groups according to cocaine use at baseline: 1 group with regular cocaine use and 1 group with irregular or no cocaine use. Results: The group of regular cocaine using opioid-dependent patients had a significantly higher severity of dependence and a higher need for treatment at baseline compared to those with irregular or no cocaine use. At the 4-year follow-up examination no differences were found between the 2 groups. Conclusions: The lack of evidence of long-term effects weakens the predictive value of the negative effect of cocaine use on outcome.