Predictors of heroin abstinence


Opiate substitution therapy (OST) for heroin dependence is recognized across the world as effective for retention in treatment and reducing illicit drug use.

Traditionally, studies have focused on heroin-only users. The high prevalence of crack/cocaine use among heroin users accessing OST in the UK however has been documented for over a decade, and national statistics show an increase in the percentage of dual users (relative to all heroin users).

The need for systematic studies of the patterns of concurrent cocaine use alongside heroin has been recognized, however the majority of studies have considered dual users as a homogeneous group.



To analyse predictors of heroin abstinence in opiate substitution therapy (OST) based on frequency of crack use and its interactions with other predictors in a clinical non-experimental setting.


Brief findings

  • For clients choosing methadone no significant predictors of heroin abstinence were found;

  • For clients choosing buprenorphine lower doses of medication, higher amounts of baseline heroin use and daily alcohol use predicted heroin use at follow up;

  • For clients choosing buprenorphine no crack use predicted heroin abstinence at follow up only when occurring either with a depression or the use of cannabis. What could this mean?



Addressing crack/cocaine use with clients presenting to services for heroin dependency could improve treatment outcomes.


Find out more about this project at:

  • Second European Conference on Addictive Behaviours and Dependencies 24th-26th October 2017, Lisbon, Portugal

Lisbon Addictions

  • The Annual conference of the Society for the Study of Addiction; 9th-10th November 2017, Newcastle upon Tyne, UK

SSA Symposium

  • Download the conference poster here


Read the authors’ manuscript here



Dr. Lynne Dawkins

Mary Bell MacLeod