Polysubstance Use: Diagnostic Challenges, Patterns of Use and Health

Jason P. Connor; Matthew J. Gullo; Angela White; Adrian B. Kelly


Curr Opin Psychiatry. 2014;27(4):269-275. 

In This Article

Prevention, Treatment, and Further Research

Prevention programs delivered in schools and the community to reduce youth substance use generally demonstrate modest efficacy, with some studies showing small short-term effects, but poor longer term outcomes.[64–66] When prevention programs that specifically target adult polysubstance users are reviewed, pervasive methodological weaknesses prevent strong conclusions being drawn about efficacy.[67] Psychological treatments for alcohol, cannabis, tobacco, and amphetamine are effective in reducing the severity of disorders, as are pharmacological approaches to opiate, nicotine, and alcohol dependence.[68] There is currently limited evidence to assess whether treating multiple substance problems concurrently is more effective than treating them individually and sequentially.

There is an intuitive appeal for targeting prevention and treatment approaches based on the individual risk profiles (T. Dietrich, S.R. Rundle-Thiele, C. Leo, J.P. Connor, in preparation).[69,70] Some promising prevention results targeting personality risk have recently been reported at 24 months' follow-up.[71] Future research may consider whether specific types of polysubstance clusters, as identified in the current review, respond better to targeted prevention and treatment approaches.

Future epidemiological research needs to move beyond the binary measures of drug use to polysubstance use profiles that incorporate measures of frequency and severity.[18,19,39,41] They could also explore longitudinal transitions in patterns of polysubstance use, particularly between age 14 and 35, in which polysubstance use frequently develops, peaks, and subsides.[25–27] The increased use of LCA and latent transition analysis[20] will help identify patterns of both 'forward' and 'backward' transitioning (widening or narrowing of drug types). These statistical technologies may be helpful in determining the timings for prevention targets for specific drug types and combinations of drugs. Future research would also benefit from more precisely identifying the source of prescription medication used for non-medical purposes. It is possible individuals that source non-prescription medicine from registered heath prescribers may represent a fundamentally different type of substance user than those who access street markets for both diverted prescription (and over-the-counter drugs) drugs and illicit drugs.