Retention in HIV Care between Testing and Treatment in Sub-Saharan Africa: A Systematic Review

Abstract

In this systematic review, Sydney Rosen and Matthew Fox find that less than one-third of patients who tested positive for HIV, but were not eligible for antiretroviral therapy (ART) when diagnosed, were retained in pre-ART care continuously.

Abstract

Background

Improving the outcomes of HIV/AIDS treatment programs in resource-limited settings requires successful linkage of patients testing positive for HIV to pre–antiretroviral therapy (ART) care and retention in pre-ART care until ART initiation. We conducted a systematic review of pre-ART retention in care in Africa.

Methods and Findings

We searched PubMed, ISI Web of Knowledge, conference abstracts, and reference lists for reports on the proportion of adult patients retained between any two points between testing positive for HIV and initiating ART in sub-Saharan African HIV/AIDS care programs. Results were categorized as Stage 1 (from HIV testing to receipt of CD4 count results or clinical staging), Stage 2 (from staging to ART eligibility), or Stage 3 (from ART eligibility to ART initiation). Medians (ranges) were reported for the proportions of patients retained in each stage. We identified 28 eligible studies. The median proportion retained in Stage 1 was 59% (35%–88%); Stage 2, 46% (31%–95%); and Stage 3, 68% (14%–84%). Most studies reported on only one stage; none followed a cohort of patients through all three stages. Enrollment criteria, terminology, end points, follow-up, and outcomes varied widely and were often poorly defined, making aggregation of results difficult. Synthesis of findings from multiple studies suggests that fewer than one-third of patients testing positive for HIV and not yet eligible for ART when diagnosed are retained continuously in care, though this estimate should be regarded with caution because of review limitations.

Conclusions

Studies of retention in pre-ART care report substantial loss of patients at every step, starting with patients who do not return for their initial CD4 count results and ending with those who do not initiate ART despite eligibility. Better health information systems that allow patients to be tracked between service delivery points are needed to properly evaluate pre-ART loss to care, and researchers should attempt to standardize the terminology, definitions, and time periods reported.

Please see later in the article for the Editors' Summary

Editors' Summary

Background

Since 1981, AIDS has killed more than 25 million people, and about 33 million people (mostly living in low- and middle-income countries) are now infected with HIV, the virus that causes AIDS. HIV gradually destroys immune system cells (including CD4 cells, a type of lymphocyte), leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-infected people died within ten years of infection. Then, in 1996, highly active antiretroviral therapy (ART) became available, and, for people living in developed countries, HIV infection became a chronic condition. Unfortunately, ART was extremely expensive, and HIV/AIDS remained a fatal illness for people living in developing countries. In 2003, governments, international agencies, and funding bodies began to implement plans to increase ART coverage in resource-limited countries. By the end of 2009, about a third of the people in these countries who needed ART (HIV-positive people whose CD4 count had dropped so low that they could not fight other infections) were receiving treatment.

Why Was This Study Done?

Unfortunately, many HIV-positive people in resource-limited countries who receive ART still do not have a normal life expectancy, often because they start ART when they have a very low CD4 count. ART is more successful if it is started before the CD4 count falls far below 350 cells/mm ³ of blood, the threshold recommended by the World Health Organization for ART initiation. Thus, if the outcomes of HIV/AIDS programs in resource-limited settings are to be improved, all individuals testing positive for HIV must receive continuous pre-ART care that includes regular CD4 counts to ensure that ART is initiated as soon as they become eligible for treatment. Before interventions can be developed to achieve this aim, it is necessary to understand where and when patients are lost to pre-ART care. In this systematic review (a study that uses predefined criteria to identify all the research on a given topic), the researchers investigate the retention of HIV-positive adults in pre-ART care in sub-Saharan Africa.

What Did the Researchers Do and Find?

The researchers identified 28 studies that included data on the proportion of adult patients retained between any two time points between testing positive for HIV and starting ART in HIV/AIDS care programs in sub-Saharan Africa. They defined three stages of pre-ART care: Stage 1, the interval between testing positive for HIV and receiving CD4 count results or being clinically assessed; Stage 2, the interval between enrollment in pre-ART care and the determination of eligibility for ART; and Stage 3, the interval between being deemed eligible for ART and treatment initiation. A median of 59% of patients were retained in Stage 1 of pre-ART care, 46% were retained in Stage 2, and 68% were retained in Stage 3. Retention rates in each stage differed greatly between studies—between 14% and 84% for Stage 3 pre-ART care, for example. Because the enrollment criteria and other characteristics of the identified studies varied widely and were often poorly defined, it was hard to combine study results. Nevertheless, the researchers estimate that, taking all the studies together, less than one-third of patients testing positive for HIV but not eligible for ART when diagnosed were retained in pre-ART care continuously.

What Do These Findings Mean?

These findings suggest that there is a substantial loss of HIV-positive patients at every stage of pre-ART care in sub-Saharan Africa. Thus, some patients receiving a positive HIV test never return for the results of their initial CD4 count, some disappear between having an initial CD4 count and becoming eligible for ART, and others fail to initiate ART after having been found eligible for treatment. Because only a few studies were identified (half of which were undertaken in South Africa) and because the quality and design of some of these studies were suboptimal, the findings of this systematic review must be treated with caution. In particular, the estimate of the overall loss of patients during pre-ART care is likely to be imprecise. The researchers call, therefore, for the implementation of better health information systems that would allow patients to be tracked between service delivery points as a way to improve the evaluation and understanding of the loss of HIV-positive patients to pre-ART care in resource-limited countries.

Additional Information

Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001056.

• Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS

• HIV InSite has comprehensive information on all aspects of HIV/AIDS

• Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on HIV/AIDS treatment and care, on HIV and AIDS in Africa and on universal access to AIDS treatment (in English and Spanish)

• The World Health Organization provides information about universal access to AIDS treatment, including the 2010 progress report (in English, French and Spanish); its 2010 ART guidelines can be downloaded (in several languages)

• The International AIDS Economics Network posts information about economic, social, and behavioral aspects of HIV care and treatment

• Up-to-date research findings about HIV care and treatment are summarized by NAM/aidsmap