CRD summary

This review found that opioid substitution treatment may help reduce human immunodeficiency virus (HIV) risk behaviours in prison, but that further research is needed. The review was well conducted in most respects and the author’s cautious conclusions appear reliable.

Authors' objectives

To evaluate the effectiveness of prison-based opioid substitution treatment for reducing injecting-related human immunodeficiency virus (HIV) risk behaviours.

Searching

PubMed, Scopus and Web of Science were searched without language restriction. Search terms were reported. An annotated bibliography of prison research was handsearched.

Study selection

Controlled studies of prison-based opioid substitution treatment versus no treatment, among prison inmates with a history of illicit opioid use, were eligible for inclusion. Opioid substitution treatment was defined as long-term treatment with methadone or buprenorphine. Studies were required to report outcomes relating to injecting drug use, needle and syringe sharing, and/or HIV incidence in prison.

In the included studies, outcomes relating to opioid and injecting drug use were measured by self-report and/or biological testing of urine or hair (where reported). Rates of institutional drug charges against inmates were also reported (but the type of drugs was not specified). It was unclear in some cases whether studies had ethics committee approval. Two studies reported follow-up data, but duration of follow-up was unclear. The included studies were set in Iran, Australia, Puerto Rico and Australia.

The author did not state how many reviewers performed the selection.

Assessment of study quality

Study validity was assessed using an adapted version of published criteria (Cochrane Consumers and Communication Review Group 2007) to assess design, treatment allocation, comparability of groups at baseline, follow-up rate and use of intention-to-treat analysis.

The author did not state how many reviewers conducted the assessment.

Data extraction

Risk ratios were calculated from event rates in the two groups, with 95% confidence intervals.

A single reviewer extracted the data.

Methods of synthesis

Studies were combined in a narrative synthesis, organised by outcome.

Results of the review

Five studies were included in the review (n=1.036 participants, range 43 to 518): one randomised controlled trial (n=253 participants), one quasi-randomised study (n=69 participants), and three non-randomised studies (n=714 participants). Groups were comparable at baseline in three studies. Follow-up rates ranged from 52 to 68% in the two studies with follow-up; neither used intention-to-treat analysis. The three other studies were cross-sectional and did not report participation rates; the representativeness of their samples was uncertain.

Illicit opioid use was significantly reduced in the treatment group compared to controls in all four studies reporting this outcome, with risk reductions ranging from 62 to 91%. In the fifth study, there was a statistically significant reduction over time in the number of institutional drug charges among treated participants compared with control groups.

Two of three relevant studies reported a significant reduction (55% and 75%) in injecting drug use in the opioid substitution treatment group compared with the control group; the third study reported no statistically significant difference between the groups.

Three studies reported a statistically significant reduction in needle and syringe sharing in the treatment group compared to controls, with risk reductions ranging from 47 to 73%. None of the studies reported HIV incidence.

The review reported risk ratios and 95% confidence intervals for all pre-specified outcomes for each study.

Authors' conclusions

Opioid substitution treatment may help to reduce HIV risk behaviours in prison, but further research is needed.

CRD commentary

The objectives and inclusion criteria of the review were clear. Relevant sources were searched for studies in any language. However, specific attempts did not seem to have been made to retrieve unpublished studies. Search dates were not reported. The review had a single author, and it appeared that study selection and validity assessment, as well as data extraction, were undertaken by this lone author; lack of an independent check of review processes meant that the review was at increased risk of reviewer bias and error.

The decision to combine the studies by narrative synthesis was appropriate, given their heterogeneity. The author noted a number of limitations in the evidence, including the small amount of data available, low rates of follow-up, lack of intentional-to-treat analysis, potentially unrepresentative samples and ethical concerns. Study quality was also taken into account in the interpretation of findings. The author advised that the results should be viewed with caution.

The review was well conducted in most respects and the author’s cautious conclusions appear reliable.

Implications of the review for practice and research

Practice: The author stated that opioid substitution treatment should be implemented in prisons as part of comprehensive HIV prevention programme, which should also include provision of condoms, and sterile injecting and tattooing equipment.

Research: The author stated that methodologically robust studies are required to guide further development and implementation of prison-based opioid substitution treatment.

Funding

Australian National Health and Medical Research Council Postgraduate Scholarship.

Bibliographic details

Larney S. Does opioid substitution treatment in prisons reduce injecting-related HIV risk behaviours? A systematic review Addiction 2010; 105(2): 216-223. [PubMed: 20078480]

Original Paper URL

http://onlinelibrary.wiley.com/doi/10.1111/j.1360-0443.2009.02826.x/abstract

Indexing Status

Subject indexing assigned by NLM

MeSH

Buprenorphine /therapeutic use; HIV Infections /prevention & control /transmission; Health Knowledge, Attitudes, Practice; Humans; Methadone /therapeutic use; Narcotics /therapeutic use; Needle Sharing; Prisons; Risk-Taking; Substance Abuse, Intravenous /prevention & control /rehabilitation

AccessionNumber

12010002144

Database entry date

08/09/2010

Record Status

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.