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Member Research & Reports

Member Research & Reports

Brown Studies Effect of Unstable Housing on HIV Treatment Biomarkers: An instrumental variables approach

Unstable housing, including homelessness, is a public policy concern for all populations, and more critically for people with a serious health condition such as HIV. Stable housing may be associated with better HIV treatment outcomes, including viral suppression, though the issue is far from settled. In a study published in Social Science & Medicine, and led by Dr. Omar Galárraga, associate professor of health services, policy and practice in the Brown University School of Public Health, the effect of unstable housing on HIV treatment biomarkers was measured, including viral suppression and adequate CD4+ T-cell count.

The study authors hypothesized that unstable housing is associated with decreased viral suppression and CD4 cell counts. Using panel data collected from participants in the Women’s Interagency HIV Study (WIHS) between 1995 and 2015, they tested for specific effect pathways, including mental health/counseling support; use of any healthcare provider; and continuity of care. These channels are consistent with, and complementary to other empirically-supported theories of change of housing investment and health.

The study found that unstable housing produces clinically-meaningful negative impact on health: it decreases the probability of viral suppression by 8.1 percentage points; and it decreases the probability of having adequate levels of CD4 cell counts by 7.9 percentage points. It further found that unstable housing reduces use of mental health/counseling by 25 percentage points, reduces use of (any) healthcare provider by 37 percentage points, and resulted in a reduction of 76.3 percentage points in the likelihood of seeing the same provider.

This study adds to the emerging body of knowledge on the impacts of socio-economic disparities, not just on self-reported health outcomes, but on objectively measured health biomarkers. Authors found that unstable housing drastically reduces both HIV viral suppression and CD4+ T-cell counts for people living with HIV; thus worsening clinical outcomes, and further exacerbating health disparities. They also show specific pathways for the effects, including use of any mental health/counseling, any healthcare, and continuity of care, which extends the empirically-observed conceptual framework. Further, this study adds to the emerging body of knowledge on the impacts of public policies to address housing instability among the poor by showing that Housing Opportunities for People with AIDS allocations per new HIV diagnosis reduce housing instability among people living with HIV.

This study has been published in Social Science & Medicine Volume 214, in the October issue.