Mass HIV Treatment and Sex Disparities in Life Expectancy: Demographic Surveillance in Rural South Africa

Abstract

Background

Women have better patient outcomes in HIV care and treatment than men in sub-Saharan Africa. We assessed—at the population level—whether and to what extent mass HIV treatment is associated with changes in sex disparities in adult life expectancy, a summary metric of survival capturing mortality across the full cascade of HIV care. We also determined sex-specific trends in HIV mortality and the distribution of HIV-related deaths in men and women prior to and at each stage of the clinical cascade.

Methods and Findings

Data were collected on all deaths occurring from 2001 to 2011 in a large population-based surveillance cohort (52,964 women and 45,688 men, ages 15 y and older) in rural KwaZulu-Natal, South Africa. Cause of death was ascertained by verbal autopsy (93% response rate). Demographic data were linked at the individual level to clinical records from the public sector HIV treatment and care program that serves the region. Annual rates of HIV-related mortality were assessed for men and women separately, and female-to-male rate ratios were estimated in exponential hazard models. Sex-specific trends in adult life expectancy and HIV-cause-deleted adult life expectancy were calculated. The proportions of HIV deaths that accrued to men and women at different stages in the HIV cascade of care were estimated annually.

Following the beginning of HIV treatment scale-up in 2004, HIV mortality declined among both men and women. Female adult life expectancy increased from 51.3 y (95% CI 49.7, 52.8) in 2003 to 64.5 y (95% CI 62.7, 66.4) in 2011, a gain of 13.2 y. Male adult life expectancy increased from 46.9 y (95% CI 45.6, 48.2) in 2003 to 55.9 y (95% CI 54.3, 57.5) in 2011, a gain of 9.0 y. The gap between female and male adult life expectancy doubled, from 4.4 y in 2003 to 8.6 y in 2011, a difference of 4.3 y (95% CI 0.9, 7.6). For women, HIV mortality declined from 1.60 deaths per 100 person-years (95% CI 1.46, 1.75) in 2003 to 0.56 per 100 person-years (95% CI 0.48, 0.65) in 2011. For men, HIV-related mortality declined from 1.71 per 100 person-years (95% CI 1.55, 1.88) to 0.76 per 100 person-years (95% CI 0.67, 0.87) in the same period. The female-to-male rate ratio for HIV mortality declined from 0.93 (95% CI 0.82–1.07) in 2003 to 0.73 (95% CI 0.60–0.89) in 2011, a statistically significant decline ( p = 0.046). In 2011, 57% and 41% of HIV-related deaths occurred among men and women, respectively, who had never sought care for HIV in spite of the widespread availability of free HIV treatment. The results presented here come from a poor rural setting in southern Africa with high HIV prevalence and high HIV treatment coverage; broader generalizability is unknown. Additionally, factors other than HIV treatment scale-up may have influenced population mortality trends.

Conclusions

Mass HIV treatment has been accompanied by faster declines in HIV mortality among women than men and a growing female–male disparity in adult life expectancy at the population level. In 2011, over half of male HIV deaths occurred in men who had never sought clinical HIV care. Interventions to increase HIV testing and linkage to care among men are urgently needed.

Abstract

Jacob Bor and colleagues use demographic data from a longitudinal surveillance cohort to identify increased gains in life expectancy among women compared to men in the years following antiretroviral therapy scale-up in rural South Africa.

Editors' Summary

Background.

AIDS has killed 39 million people over the past three decades, and about 35 million people (including 25 million living in sub-Saharan Africa) are currently infected with HIV, the retrovirus that causes AIDS. HIV destroys immune system cells, leaving HIV-positive individuals susceptible to other serious infections. Early in the AIDS epidemic, most HIV-positive individuals died within ten years of infection. Then, in 1996, effective antiretroviral therapy (ART) became available. For people living in high-income countries, HIV infection became a chronic condition, but HIV/AIDS remained largely untreated and fatal in resource-limited countries. In 2003, the international community began to work towards achieving universal access to ART. Now, at least a third of people living with HIV have access to ART, the global rate of AIDS-related deaths has fallen by more than a third from its 2005 peak, and the life expectancy (how long a person is likely to live based on their year of their birth, their current age, and other demographic factors) of HIV-positive adults has markedly increased.

Why Was This Study Done?

Although ART has been provided without charge to patients in South African public clinics since 2004, HIV/AIDS remains the leading cause of death in many parts of South Africa. Reducing the lingering burden of HIV mortality is a policy priority. Prior studies have found worse outcomes among men in HIV care and treatment. Here, the researchers assess the evolution of sex disparities in life expectancy and HIV mortality rates at the population level with the scale-up of ART in a rural region of KwaZulu-Natal, South Africa, where 29% of the population is HIV-positive. Different trends in life expectancy for men and women following ART scale-up may reflect differences in the underlying burden of HIV disease—women tend to be infected and die at younger ages—as well as differences in access to HIV testing, care, and treatment. The researchers also assess where in the cascade of HIV care and treatment HIV mortality occurs for men and women. Knowing more about sex-specific trends in population life expectancy and where the lingering burden of HIV mortality occurs could help experts design strategies to further reduce HIV mortality in regions where free ART is widely available.

What Did the Researchers Do and Find?

The researchers linked demographic data obtained through regular household surveys, including all deaths occurring between 2001 and 2011, for nearly 100,000 adults living in rural KwaZulu-Natal to clinical records held by the public sector HIV treatment and care program. In addition, trained nurses visited households where there had been a death and collected data that were used to determine the probable cause of death (verbal autopsy). Analysis of these data indicated that, between 2003 and 2011, female adult life expectancy increased by 13.2 years (from 51.3 years to 64.5 years), whereas male life expectancy increased by only 9 years (from 46.9 years to 55.9 years). Thus, the gap between female and male adult life expectancy doubled between 2003 and 2011. Moreover, although HIV-related mortality among women and men was similar in 2003, in 2011 women were 27% less likely to die from HIV than men. With the scale-up of ART, male sex has emerged as a risk factor for HIV mortality at the population level. Finally, in 2011, 55% of all male HIV-related deaths and 40% of all female HIV-related deaths occurred among men and women who had never sought care for HIV/AIDS.

What Do These Findings Mean?

These findings suggest that although the mass provision of free ART in South Africa has coincided with a reduction in HIV-related mortality among both men and women, ART scale-up has been accompanied by faster declines in HIV-related deaths among women than men and by a growing female–male disparity in adult life expectancy. Notably, these findings also indicate that despite the wide availability of ART, about half of all HIV-related deaths in the study population occurred among people who had never sought care for HIV. The use of verbal autopsy to determine the probable cause of death may limit the accuracy of these findings, and factors other than the scale-up of ART may have influenced the population mortality trends. Moreover, these findings may not be generalizable to other populations. However, these results highlight the need for further research to understand why men are not as likely as women to seek and adhere to HIV care and treatment, and to design effective interventions to increase the uptake of HIV services among men. Without better outreach to men, the researchers conclude, the full benefits of mass ART provision will not be realized.

Additional Information.

This list of resources contains links that can be accessed when viewing the PDF on a device or via the online version of the article at http://dx.doi.org/10.1371/journal.pmed.1001905.

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

• NAM/aidsmap provides basic information about HIV/AIDS, summaries of recent research findings on HIV care and treatment, and personal stories about living with HIV/AIDS

• Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on universal access to ART and on HIV/AIDS in South Africa; Avert also provides personal stories about living with HIV/AIDS

• The World Health Organization (WHO) provides information on all aspects of HIV/AIDS (in several languages), including its Consolidated Guidelines on the Use of Antiretroviral Therapy for Treating and Preventing HIV Infection and information on the WHO/UNAIDS Treatment 2.0 strategy, an initiative to expand access to HIV testing and ART

• The UNAIDS Fast-Track Strategy to End the AIDS Epidemic by 2030 provides up-to-date information about the AIDS epidemic and efforts to halt it, including progress towards universal access to antiretroviral therapy; UNAIDS also provides detailed information about HIV/AIDS in South Africa

• More information about the population-based surveillance cohort that provided the data for this study is available from the Africa Centre for Population Health website