HIV-infected patients and treatment outcomes: an equivalence study of community-located, primary care-based HIV treatment vs. hospital-based specialty care in the Bronx, New York

The HIV-infected population in the USA is expanding as patients survive longer and new infections are identified. In many areas, particularly rural/medically underserved regions, there is a growing shortage of providers with sufficient HIV expertise. HIV services incorporated into community-based (CB), primary care settings may therefore improve the distribution and delivery of HIV treatment. Our objective was to describe/compare patients and treatment outcomes in two settings: a community-located, primary care-based HIV program, and a hospital-based (HB) specialty center. CB providers had on-site access to generalist HIV experts. The hospital center was staffed primarily by infectious disease physicians. This was a retrospective cohort study of 854 HIV-positive adults initiating care between 1/2005 and 12/2007 within an academic medical center network in the Bronx, NY. Treatment outcomes were virologic and immunologic response at 16-32 and 48 weeks, respectively, after combination antiretroviral therapy (cART) initiation. We found that HB subjects presented with a higher prevalence of AIDS (59% vs. 46%, p<0.01) and lower initial CD4 (385 vs. 437, p<0.05) than CB subjects. Among 178 community vs. 237 hospital subjects starting cART, 66% vs. 62% achieved virologic suppression (95% confidence interval (CI) difference -0.14-0.06) and 49% vs. 59% achieved immunologic success, defined as a 100 cell/mm³ increase in CD4 (95% CI difference 0.00-0.19). The multivariate-adjusted likelihoods of achieving viral suppression [OR=1.24 (95% CI 0.69-2.33)] and immunologic success [OR=0.76 (95% CI 0.47-1.21)] were not statistically significant for community vs. hospital subjects. Because this was an observational study, propensity scores were used to address potential selection bias when subjects presented to a particular setting. In conclusion, HIV-infected patients initiate care at CB clinics earlier and with less advanced HIV disease. Treatment outcomes are comparable to those at a HB specialty center, suggesting that HIV care can be delivered effectively in community settings.