Evaluating strategies to improve HIV care outcomes in Kenya: a modelling study

Abstract

Background With expanded access to antiretroviral therapy (ART) in sub-Saharan Africa, HIV mortality has decreased, yet life-years are still lost to AIDS. Strengthening of treatment programmes is a priority. We examined the state of an HIV care programme in K enya and assessed interventions to improve the impact of ART programmes on population health. Methods W e created an individual-based mathematical model to describe the HIV epidemic and the experiences of care among adults infected with HIV in K enya. We calibrated the model to a longitudinal dataset from the A cademic M odel Providing Access To Healthcare (known as AMPATH) programme describing the routes into care, losses from care, and clinical outcomes. We simulated the cost and eff ect of interventions at diff erent stages of HIV care, including improvements to diagnosis, linkage to care, retention and adherence of ART, immediate ART eligibility, and a universal test-and-treat strategy. Findings We estimate that, of people dying from AIDS between 2010 and 2030, most will have initiated treatment (61%), but many will never have been diagnosed (25%) or will have been diagnosed but never started ART (14%). M any interventions targeting a single stage of the health-care cascade were likely to be cost-eff ective, but any individual intervention averted only a small percentage of deaths because the eff ect is attenuated by other weaknesses in care. H owever, a combination of fi ve interventions (including improved linkage, point-of-care CD4 testing, voluntary counselling and testing with point-of-care CD4, and outreach to improve retention in pre-ART care and on-ART) would have a much larger impact, averting 1·10 million disability-adjusted life-years (DALYs) and 25% of expected new infections and would probably be cost-eff ective (US$571 per DALY averted). This strategy would improve health more effi ciently than a universal test-and-treat intervention if there were no accompanying improvements to care ($1760 per DALY averted). Interpretation When resources are limited, combinations of interventions to improve care should be prioritised over high-cost strategies such as universal test-and-treat strategy , especially if this is not accompanied by improvements to the care cascade. International guidance on ART should refl ect alternative routes to programme strengthening and encourage country programmes to evaluate the costs and population-health impact in addition to the clinical benefi ts of immediate initiation. F unding Bill & Melinda Gates Foundation, United States Agency for International Development, National Institutes of Health