Setting up Vancouver's homeless HIV patients with supportive housing could dramatically increase the number who stick with anti-retroviral drugs that can reduce the disease to undetectable levels and prevent transmission to others, according to a new study presented on Tuesday at an international HIV/AIDS conference.
The finding underscores the importance of a housing-first model for the most marginalized patients, who often have mental-health and addiction issues, according to the lead author of a study by U.S. and Canadian researchers presented at the International AIDS Society conference.
Over the past decade, researchers on Vancouver's Downtown Eastside interviewed 708 hard-to-treat HIV patients, about a third of whom reported living on the streets. The vast majority – 94 per cent – were injection drug users.
In tests at a clinic at the B.C. Centre for Excellence in HIV/AIDS a month after each interview, researchers recorded the level of the virus detected in the anonymous subjects.
Their data showed 38 per cent of all the participants had suppressed their HIV through antitretroviral drugs to the point where it was undetectable, but only 22 per cent of the homeless participants reached those levels.
Based on those results, researchers predict that finding those patients supporting housing could increase the proportion who take anti-retroviral drugs by 80 per cent.
The study had 223 homeless participants, 49 of whom adhered to the regimen of drugs and ended up with undetectable levels of the virus. The study predicted that, with housing, that number could rise to 89 – an 80 per cent increase.
"We see very clearly that there are very strong benefits to helping people adhere to their HIV treatment in shelter environments," said the team's presenter, Brandon Marshall of Brown University.
The study, which was peer reviewed before the conference and will be submitted to a medical journal soon, was conducted by the B.C. Centre for Excellence in HIV/AIDS and the medical faculties of Brown University and the University of British Columbia.
Prof. Marshall said more research is needed, but the data show money spent on supportive housing for such patients will save public money, because more will stick with the treatment-as-prevention model developed at the B.C. centre. This strategy of treating HIV aggressively with anti-retroviral drugs has been proven to make it much less likely patients will infect others. Government's around the world are increasingly adopting it.
Citing a 2007 U.S. study, Prof. Marshall said any program spending $10,000 to $12,000 per person each year to house infected drug users could break even if just one HIV infection is averted for every 64 people given a roof over their heads.
Another study, which was presented on Tuesday by the B.C. centre, showed that homeless patients trying anti-retroviral treatments for the first time were more likely to get off the streets permanently, start addiction treatment and begin a romantic relationship.
The treatment-as-prevention strategy is credited with reducing cases of HIV in B.C. by two thirds from 1996 to 2012. Research from M. J. Milloy and his colleagues at the centre showed deaths related to the disease dropped 82 per cent during roughly that same period.
Still, many of the province's most marginalized patients still face barriers to getting this treatment, which has been adopted by the UN, Dr. Milloy said.
"These are folks who are going to jail, who are dealing with addiction issues, and so often their HIV treatment outcomes are not as good as other groups in the pandemic – and housing is a big part of that," Dr. Milloy said.
Prof. Marshall, who did his PhD at the University of British Columbia, ended his presentation by reiterating the maxim that "housing is a human right."