The impact of integrated HIV care on patient health outcomes.

Background: Control of viral replication through combination antiretroviral therapy (cART) improves patient health outcomes. Yet many HIV-infected patients have comorbidities that pose social and clinical barriers to achieving viral suppression. Integration of subspecialty services into HIV primary care may overcome such barriers.

Objective: To evaluate effect of integrated HIV care (IHC) on suppression of HIV replication.

Research Design: A retrospective cohort study of HIV patients from 5 Veterans Affairs healthcare facilities 2000 to 2006.

Subjects: Patients with >3 months of follow-up, sufficient baseline HIV severity, on cART.

Measures: We measured and ranked Integrated Care at the facilities. These rankings were applied to patient visits to form an index of IHC utilization. We evaluated effect of IHC utilization on likelihood of achieving viral suppression while on cART, controlling for demographic and clinical factors using survival analysis.

Results: : The 1018 HIV-infected patients eligible for analysis had substantial barriers to responding to cART: 93% had comorbidities with mean 3.2 comorbidities per patient (SD = 2.0); 52% achieved viral suppression in median 231 days (SD = 411.6). Patients visiting clinics that offered hepatitis, psychiatric, psychologic, and social services in addition to HIV primary care were 3.1 times more likely to achieve viral suppression than patients visiting clinics which offered only HIV primary care (hazard ratio = 3.1, P < 0.001).

Conclusions: Patients who visited IHC clinics were more likely to achieve viral suppression while on cART. Future research should investigate which elements of Integrated Care are most associated with viral control and what role provider experience plays in this association.