A
meta-analysis of sexual risk behaviour reduction using the
counselling technique known as motivational interviewing has found
little evidence of efficacy, the Tenth AIDS Impact conference heard
this week.
Researcher
Rigmor Berg, of the Norwegian Knowledge Centre for Health Services in
Oslo, told the conference that a meta-analysis of ten randomised
controlled trials of motivational interviewing as a technique for
reducing sexual risk found only one outcome measure, alcohol use, in
which using the technique resulted in a statistically superior outcome when compared with what was on offer in the control arm.
Motivational interviewing produced no statistically significant
difference over control for outcome measures such as unprotected anal
intercourse, number of sexual partners, or condom use.
Motivational
interviewing (MI) is a counselling technique developed by
psychologists William R Miller and Stephen Rollnick in the 1980s
(Rollnick and Miller). The first paper on MI was published in 1983
(Miller). The technique is a development of person-centred
counselling in which the counsellor – while acknowledging clients'
reluctance to change or fear of change – gently points out and 'develops'
the discrepancies between the way the client is and the way they
would like to be. The aim is to facilitate change that the client is
already contemplating.
The
technique has proved effective in treating problematic drinking (with
a 50% decrease in drinking compared with control or placebo
treatments), eating disorders, and drug misuse, although the authors
of a meta-analysis of randomised controlled trials in 2003 (Burke)
were already warning that they had not found evidence of efficacy in
changing HIV risk behaviours.
The
importance of MI is that it has become recommended as a standard
behavioural intervention by bodies such as NICE in the UK, for a number of
populations, such as drug-using
adolescents, and is mentioned as a successful intervention in gay
men at risk of HIV in the evidence
supporting the NICE guideline on the Prevention
of sexually transmitted infections and under 18 conceptions
issued in 2007 (Downing). MI as a technique is amongst those taught
to healthcare staff in HIV and STI clinics.
For
the present meta-analysis, Dr Berg and her team found ten randomised
controlled trials of MI designed to answer the question: “What is
the effectiveness of behavioural interventions adapting the
principles and techniques of MI on HIV-risk behaviours for men who
have sex with men?”
Out
of 155 outcome measures from the ten MI trials, she found ten
outcomes that achieved statistical significance in individual trials.
These were all behavioural outcomes such as frequency of unprotected
sex, number of sexual partners, and condom use. However when these
outcomes were combined in the meta-analysis, none retained
statistical significance.
The overall improvements in outcomes over
the meta-analysis included a 6% reduction in unprotected anal sex
with casual partners, a 2% reduction with primary partners, and a 6%
increase in condom use. There was a reduction of about one-third in
sexual partners over the short term but again this was not
statistically significant. The only outcome measure that remained
significant was that, in the studies measuring alcohol use, MI more
than halved alcohol consumption in the short term though this lost
significance over long-term follow-up.
Only
a few trials measured biological outcomes such as STIs and none were
statistically significant. Dr Berg found one trial in which MI
produced a clinically, but not statistically, significant reduction
in HIV infections. This, the EXPLORE study, was one of the largest
trials of a behavioural intervention to reduce HIV ever conducted,
involving 4295 US gay men at risk of HIV, and used MI as one of its
components in its 'ten sessions plus top-up' counselling package. It
produced a 16% reduction in HIV infections in men given MI sessions
compared with control, but this was not statistically significant.
Dr
Berg commented that it was interesting that the only behaviour MI
seemed to have a consistent effect on, at least in the short term,
was drinking, which bore out its efficacy in studies in other
populations.
She
commented that the reason MI might not be successful in sexual risk
behaviour was that sexual risk was a decision shared between two
people, and the psychosocial theories underlying techniques such as
MI assume that risk behaviours are under the control of the
individual – as they are when the individual is trying to do
something like stop drinking.
She
commented: “The effectiveness of MI as a prevention strategy for
unsafe sexual and substance use behaviours among men who have sex
with men does not appear promising, though to dismiss it as an
intervention for all HIV risk behaviours among all groups of MSM is
premature."