“We talk a lot about the success of treatment as prevention
in Vancouver, but we always need to make sure people understand that this
requires an integration of various approaches,” Dr Evan Wood of the University of
British Columbia said in a plenary presentation to the Eighth International
AIDS Society Conference (IAS 2015) in Vancouver, Canada, last week.
HIV diagnoses in people who inject drugs have fallen by more
than 90% since the peak of the epidemic in 1996. This success has been
achieved, Wood said, through a combination of community empowerment, harm
reduction, treatment for addictions and universal access to HIV treatment and
care. Nonetheless, the criminalisation and marginalisation of people who use
drugs remained major obstacles.
“The success of treatment as prevention in injecting drug
users in Vancouver has been phenomenal,” his colleague Professor Julio Montaner said in
another session. “The reason why it’s working so well is because there is a
synergy between the needle exchange, the supervised injection site, the
methadone programme and the treatment as prevention.”
He acknowledged that infections have not fallen so far in
men who have sex with men. For this group, there aren’t other highly effective
interventions to provide together with treatment as prevention, he suggested.
The treatment cascade in people who inject drugs
In many parts of the world, people who inject drugs have
poor access to health services and have not fully benefited from HIV treatment.
But MJ Milloy of the British Columbia Centre for Excellence in HIV/AIDS
outlined improvements in the local treatment cascade for people who inject
drugs in recent years. In 2006, 30% of those in care were taking treatment and
had an undetectable viral. By 2012, the figure had risen to 71%.
Considerable efforts have been made to engage drug users
with HIV and harm reduction services, which are always free of charge for those
who need them.
The data come from the ACCESS cohort of people living with
HIV who inject drugs in Vancouver. A series of analyses from this cohort
presented to the conference shows the importance of opioid substitution therapy
and social factors in making progress along the HIV treatment cascade.
This ongoing prospective observational cohort began in 1996
and currently has over 800 people in it. Two-thirds are men, the average age is
43, three-quarters are homeless or in unstable housing, two-thirds live in
Vancouver’s Downtown Eastside (an area with many social problems), 15% have
recently been incarcerated, 17% inject heroin daily and 36% smoke crack daily.
One analysis examined how long it took members of the cohort
to start treatment after being diagnosed with HIV, and the factors that delayed
or facilitated this. Individuals who were taking methadone as
opioid substitution therapy tended to start treatment promptly. People who
generated income in ‘informal’ ways (selling sex, dealing drugs, through crime,
begging, etc.) had a slower uptake of treatment, as did people who had been in prison. But there was no association between drug-using practices
and slower uptake of treatment.
The next analysis looked at adherence, specifically transitions
from poor adherence to good adherence, or from good to poor adherence. Once
again, taking methadone as opioid substitution therapy promoted good outcomes.
Continuing to inject drugs, recent incarceration, recent homelessness, sex work,
and already having a low CD4 cell count made it harder to achieve good
outcomes.
Just as social factors can be barriers to good treatment
outcomes, the final analysis from the cohort suggested that treatment success
is associated with subsequent social benefits. People who achieved optimal
adherence to HIV treatment were more likely than others to cease to earn money
in informal ways and were also more likely to transition out of homelessness.
They also appeared to be more likely to start a romantic relationship, although
this wasn’t quite statistically significant.