The effect of complete integration of HIV and TB services on time to initiation of antiretroviral therapy: a before-after study

Abstract

Background: Studies have shown that early ART initiation in TB/HIV co-infected patients lowers mortality. One way to implement earlier ART commencement could be through integration of TB and HIV services, a more efficient model of care than separate, vertical programs. We present a model of full TB/HIV integration and estimate its effect on time to initiation of ART.

Methodology/principal findings: We retrospectively reviewed TB registers and clinical notes of 209 TB/HIV co-infected adults with a CD4 count <250 cells/µl and registered for TB treatment at one primary care clinic in a South African township between June 2008 and May 2009. Using Kaplan-Meier and Cox proportional hazard analysis, we compared time between initiation of TB treatment and ART for the periods before and after full, "one-stop shop" integration of TB and HIV services (in December 2009). Potential confounders were determined a priori through directed acyclic graphs. Robustness of assumptions was investigated by sensitivity analyses. The analysis included 188 patients (100 pre- and 88 post-integration), yielding 56 person-years of observation. Baseline characteristics of the two groups were similar. Median time to ART initiation decreased from 147 days (95% confidence interval [CI] 85-188) before integration of services to 75 days (95% CI 52-119) post-integration. In adjusted analyses, patients attending the clinic post-integration were 1.60 times (95% CI 1.11-2.29) more likely to have started ART relative to the pre-integration period. Sensitivity analyses supported these findings.

Conclusions/significance: Full TB/HIV care integration is feasible and led to a 60% increased chance of co-infected patients starting ART, while reducing time to ART initiation by an average of 72 days. Although these estimates should be confirmed through larger studies, they suggest that scale-up of full TB/HIV service integration in high TB/HIV prevalence settings may shorten time to ART initiation, which might reduce excess mortality and morbidity.

Figure 1. Roles of health staff in Town 2 clinic after TB/HIV service integration.

Model of care as it was implemented in Town 2 clinic in December 2008.

Figure 2. Flow chart of patients included in the study in Town 2 clinic from June 2008 to May 2009.

Legend: TB, tuberculosis; ART, antiretroviral treatment; TFO, transferred out; LTFU, lost to follow-up.

Figure 3. Kaplan-Meier curve for time from start of TB treatment to ART initiation for before and after service integration in Town 2 clinic from June 2008 to May 2009.