Two meta-analyses of HIV-prevention interventions
specifically directed at people with HIV were published in 2006, finally
amending the dearth of review-level research in the area – although they still
concentrate entirely on US studies.
In the first,1
Nicole Crepaz of the Centers for Disease Control and Prevention (CDC) sifted
through 310 studies of prevention programmes for people with HIV and filtered
out all but the twelve whose standard of evidence stood up to the most rigorous
scientific scrutiny. In total, 4052 people with HIV participated in these
twelve programmes.
Crepaz concluded that HIV-positive people responded at least
as well as HIV-negative people, and possibly better, to prevention
interventions. She found a significant average 43% reduction of sexual-risk
incidents in participants in the twelve programmes (OR 0.57), and a 79%
reduction in STI incidence (OR
0.21, though only a minority of programmes measured this, and the 95%
confidence interval was very wide).
By comparing one study with another, Crepaz found that the
most effective interventions were ones that:
- specifically taught people how to negotiate
condom use and safer sex as their main focus
- included help for other aspects of living with
HIV, such as disclosing status, medication adherence and maintaining
self-esteem
- were intensive, that is, which involved at least
ten sessions delivered over at least three months
- were delivered in a clinical setting or at a
voluntary organisation that already provided services to people with HIV,
rather than in outreach or community settings
- were at least partly delivered by professional
counsellors
- were at least partly delivered on a one-to-one
basis.
Crepaz found that the least
effective programmes were those which simply delivered information on
transmission risk and condom effectiveness.
In the second review,2
Blair T Johnson of the University
of Connecticut analysed
15 studies, including some that Crepaz had also analysed. Some of the studies
actually covered more than one intervention, so Johnson was able to study a
total of 19 different interventions.
Programmes used varied techniques, such as group therapy,
support, role plays, videos, telephone support and one-to-one counselling, and
lasted from 18 days to 45 weeks.
Johnson found that, on average, they produced an overall
increase in condom use of 16% relative to baseline – not as good as
Albarracin’s ‘active’ programmes, but as good as, or better, than her ‘passive’
ones. Johnson, like Albarracin, used this measure of effectiveness as it was
the one used most frequently as the measure of success.
However, Johnson found no change whatsoever in the number of
partners people had after intervention. Only 7 out of the 19 programmes
measured if the number of partners changed, however, and Johnson suggests that
this may have been confounded by people doing things not measured by
researchers instead of reducing partners, such as serosorting. The most
effective, a 2000 programme directed at HIV-positive teenagers in Los Angeles, increased
their condom use by 82% compared with a control group. However, some were
unsuccessful, and the only non-US programme, directed at HIV-positive people in
Tanzania,
actually reduced condom use by 25%. Johnson found that programmes that worked
had three characteristics.
Firstly, they tended to be directed at younger people.
Programmes where the average age of participants was 20 worked five times
better than ones directed at 40 year olds. Johnson hypothesised that older
people tend more often to be in long-term relationships where sexual habits are
harder to shift, and says that better interventions for long-term couples where
one partner has HIV need to be devised.
Secondly, the ones that worked were either motivational or
taught people behavioural skills, and programmes which did both worked even
better. ‘Motivational’ was the word Johnson used for programmes that provided
things that improved participants’ overall quality of life such as increased
social support or self-confidence.
Programmes that provided information on HIV risk alone had
no effect; ones that added in either motivation or behavioural skills increased
condom use by 12%; and ones providing all three things increased it by 33%.
Thirdly, and disappointingly, programmes directed at gay men
did not work, by and large, and, conversely, ones that excluded gay men were
effective, increasing condom use by 42%.
However, Johnson does not see this as evidence that gay men
are uniquely deaf to safer-sex advice and support. He points out that not one
single programme directed at gay men provided both ingredients proven to be
necessary – they either provided greater social support or taught behavioural
skills, but not both.
Johnson criticises the lack of scientific research into ways
of helping HIV-positive people maintain safer sex and reduce HIV transmission.
He comments:
“Perhaps the most
surprising finding of this work is that more than two decades into the
epidemic, there have been so few randomly-controlled trials of interventions
that focus on people living with HIV, though there have been literally hundreds
of studies conducted with uninfected populations. There is an urgent need for
research in this area.”