Michel Garenne

Implications of mortality transition for primary health care in rural South Africa: a population-based surveillance study.

Summary Background In southern Africa, a substantial health transition is underway, with the heavy burden of chronic infectious illness (HIV/AIDS and tuberculosis) paralleled by the growing threat of non-communicable diseases. We investigated the extent and nature of this health transition and considered the implications for primary health care. Methods Health and sociodemographic surveillance started in the Agincourt subdistrict, rural South Africa, in 1992. In a population of 70 000, deaths (n=6153) were rigorously monitored with a validated verbal autopsy instrument to establish probable cause. We used age-standardised analyses to investigate the dynamics of the mortality transition by comparing the period 2002–05 with 1992–94. Findings Mortality from chronic non-communicable disease ranked highest in adults aged 50 years and older in 1992–94 (41% of deaths [123/298]), whereas acute diarrhoea and malnutrition accounted for 37% of deaths (59/158) in children younger than 5 years. Since then, all-cause mortality increased substantially (risk ratio 1·87 [95% CI 1·73–2·03]; p<0·0001) because of a six-fold rise in deaths from infectious disease affecting most age and sex groups (5·98 [4·85–7·38]; p<0·0001), and a modest increase in deaths from non-communicable disease (1·15 [0·99–1·33]; p=0·066). The change in female risk of death from HIV and tuberculosis (15·06 [8·88–27·76]; p<0·0001) was almost double that of the change in male risk (8·13 [5·55–12·36]; p<0·0001). The burden of disorders requiring chronic care increased disproportionately compared with that requiring acute care (2·63 [2·30–3·01]; p<0·0001 vs 1·31 [1·12–1·55]; p=0·0003). Interpretation Mortality from non-communicable disease remains prominent despite the sustained increase in deaths from chronic infectious disease. The implications for primary health-care systems are substantial, with integrated chronic care based on scaled-up delivery of antiretroviral therapy needed to address this expanding burden. Funding The Wellcome Trust, UK; University of the Witwatersrand, Medical Research Council, and Anglo American and De Beers Chairmans Fund, South Africa; the European Union; Andrew W Mellon Foundation, Henry J Kaiser Family Foundation, and National Institute on Aging, National Institutes of Health, USA.

Research into health, population and social transitions in rural South Africa: Data and methods of the Agincourt Health and Demographic Surveillance System

Rationale for study: Vital registration is generally lacking in infrastructurally weak areas where health and development problems are most pressing. Health and demographic surveillance is a response to the lack of a valid information base that can provide high-quality longitudinal data on population dynamics, health, and social change to inform policy and practice. Design and measurement procedures: Continuous demographic monitoring of an entire geographically defined population involves a multi-round, prospective community study, with annual recording of all vital events (births, deaths, migrations). Status observations and special modules add value to particular research areas. A verbal autopsy is conducted on every death to determine its probable cause. A geographic surveillance system supports spatial analyses, and strengthens field management. Population and sample size considerations: Health and demographic surveillance covers the Agincourt sub-district population, sited in rural north-eastern South Africa, of some 70,000 people (nearly a third are Mozambican immigrants) in 21 villages and 11,700 households. Data enumerated are consistent or more detailed when compared with national sources; strategies to improve incomplete data, such as counts of perinatal deaths, have been introduced with positive effect. Basic characteristics: A major health and demographic transition was documented over a 12-year period with marked changes in population structure, escalating mortality, declining fertility, and high levels of temporary migration increasing particularly amongst women. A dual burden of infectious and non-communicable disease exists against a background of dramatically progressing HIV/AIDS. Potential and research questions: Health and demographic surveillance sites — fundamental to the INDEPTH Network — generate research questions and hypotheses from empirical data, highlight health, social and population priorities, provide cost-effective support for diverse study designs, and track population change and the impact of interventions over time.

What’s new? Investigating risk factors for severe childhood malnutrition in a high HIV prevalence South African setting

Aim: To identify risk factors for severe childhood malnutrition in a rural South African district with a high HIV/AIDS prevalence. Design: Case-control study. Setting: Bushbuckridge District, Limpopo Province, South Africa. Participants: 100 children with severe malnutrition (marasmus, kwashiorkor, and marasmic kwashiorkor) were compared with 200 better nourished (>-2 SD weight-for-age) controls, matched by age and village of residence. Bivariate and multivariate analyses were conducted on a variety of biological and social risk factors. Results: HIV status was known only for a minority of cases (39%), of whom 87% were HIV positive, while 45% of controls were stunted. In multivariate analysis, risk factors for severe malnutrition included suspicion of HIV in the family (parents or children) (OR 217.7, 95% CI 22.7—2091.3), poor weaning practices (OR 3.0, 95% CI 2.0—4.6), parental death (OR 38.0, 95% CI 3.8—385.3), male sex (OR 2.7, 95% CI 1.2—6.0), and higher birth order (third child or higher) (OR 2.3, 95% CI 1.0—5.1). Protective factors included a diverse food intake (OR 0.53, 95% CI 0.41—0.67) and receipt of a state child support grant (OR 0.44, 95% CI 0.20—0.97). A borderline association existed for family wealth (OR 0.9 per unit, 95% CI 0.83—1.0), father smoking marijuana (OR 3.9, 95% CI 1.1— 14.5), and history of a pulmonary tuberculosis contact (OR 3.2, 95% CI 0.9—11.0). Conclusions: Despite the increasing contribution of HIV to the development of severe malnutrition, traditional risk factors such as poor nutrition, parental disadvantage and illness, poverty, and social inequity remain important contributors to the prevalence of severe malnutrition. Interventions aiming to prevent and reduce severe childhood malnutrition in high HIV prevalence settings need to encompass the various dimensions of the disease: nutritional, economic, and social, and address the prevention and treatment of HIV/AIDS.

Accuracy of Indirect Estimates of Maternal Mortality: A Simulation Model

A simulation model was developed to test the accuracy of indirect estimates of maternal mortality (the sisterhood method). The model generated a first generation of grandmothers, a second generation of mothers (with brothers and sisters), and a third generation of children (births). In the second generation, maternal mortality was introduced. Empirical values for the parameters of fertility and mortality were taken from a prospective survey in Senegal (Niakhar). Results based on 100 simulations of the same situation revealed several limitations of the sisterhood method: The indirect estimates could fall as far as 33 percent from the true values on individual cases; the indirect estimates tended to be systematically higher than the direct estimates; their range was wider, as were their confidence intervals; and biases were particularly strong for the younger age groups of respondents. Reasons for these biases are explored.

Convergence in fertility of South Africans and Mozambicans in rural South Africa, 1993-2009

Background : Although there are significant numbers of people displaced by war in Africa, very little is known about long-term changes in the fertility of refugees. Refugees of the Mozambican civil war (1977–1992) settled in many neighbouring countries, including South Africa. A large number of Mozambican refugees settled within the Agincourt sub-district, underpinned by a Health and Socio-demographic Surveillance Site (AHDSS), established in 1992, and have remained there. The AHDSS data provide a unique opportunity to study changes in fertility over time and the role that the fertility of self-settled refugee populations plays in the overall fertility level of the host community, a highly relevant factor in many areas of sub-Saharan Africa. Objectives : To examine the change in fertility of former Mozambican self-settled refugees over a period of 16 years and to compare the overall fertility and fertility patterns of Mozambicans to host South Africans. Design : Prospective data from the AHDSS on births from 1993 to 2009 were used to compare fertility trends and patterns and to examine socio-economic factors that may be associated with fertility change. Results : There has been a sharp decline in fertility in the Mozambican population and convergence in fertility patterns of Mozambican and local South African women. The convergence of fertility patterns coincides with a convergence in other socio-economic factors. Conclusion : The fertility of Mozambicans has decreased significantly and Mozambicans are adopting the childbearing patterns of South African women. The decline in Mozambican fertility has occurred alongside socio-economic gains. There remains, however, high unemployment and endemic poverty in the area and fertility is not likely to decrease further without increased delivery of family planning to adolescents and increased education and job opportunities for women.BACKGROUND Although there are significant numbers of people displaced by war in Africa, very little is known about long-term changes in the fertility of refugees. Refugees of the Mozambican civil war (1977-1992) settled in many neighbouring countries, including South Africa. A large number of Mozambican refugees settled within the Agincourt sub-district, underpinned by a Health and Socio-demographic Surveillance Site (AHDSS), established in 1992, and have remained there. The AHDSS data provide a unique opportunity to study changes in fertility over time and the role that the fertility of self-settled refugee populations plays in the overall fertility level of the host community, a highly relevant factor in many areas of sub-Saharan Africa. OBJECTIVES To examine the change in fertility of former Mozambican self-settled refugees over a period of 16 years and to compare the overall fertility and fertility patterns of Mozambicans to host South Africans. DESIGN Prospective data from the AHDSS on births from 1993 to 2009 were used to compare fertility trends and patterns and to examine socio-economic factors that may be associated with fertility change. RESULTS There has been a sharp decline in fertility in the Mozambican population and convergence in fertility patterns of Mozambican and local South African women. The convergence of fertility patterns coincides with a convergence in other socio-economic factors. CONCLUSION The fertility of Mozambicans has decreased significantly and Mozambicans are adopting the childbearing patterns of South African women. The decline in Mozambican fertility has occurred alongside socio-economic gains. There remains, however, high unemployment and endemic poverty in the area and fertility is not likely to decrease further without increased delivery of family planning to adolescents and increased education and job opportunities for women.

Direct and indirect estimates of maternal mortality in rural Burkina Faso.

A retrospective study of maternal mortality was conducted in Nouna, a rural area of Burkina Faso in 1992. Strong evidence was found of a major mortality decline among children and young adults over the 50 years preceding the study: The estimated life expectancy of 36 years in around 1945 rose to 58 years in 1991. Direct and indirect (using the sisterhood method) estimates of the maternal mortality ratio (MMR) were compared. Overall, the direct estimate of the MMR (389 deaths per 100,000 live births) for women aged 15 and older was slightly lower than the indirect estimate (428 deaths per 100,000). Taking into account the biases involved in the use of information obtained from sisters, the direct estimates indicated a marked decline in maternal mortality over time from 569 deaths per 100,000 around 1941 to 305 deaths around 1987. The validity of both data and approach, as well as the discrepancies between the direct and indirect methods, are discussed.

Demographic Evidence of Sex Differences in Vulnerability to Infectious Diseases

To the Editor—The journals recent supplement on sex differences in susceptibility and response to infectious diseases was an excellent initiative for promoting research on a neglected topic of major interest [1–8]. If, in general, males show a higher susceptibility to many infectious diseases, the reviews displayed a number of infectious and autoimmune diseases for which females are more vulnerable. Differential vulnerability between males and females may come from exposure, infection (local or systemic), immune reaction, or a combination of these factors. Evidence came mainly from medicine, epidemiology (direct observation), and biology (animal models and in vivo observation). I address another dimension: demographic evidence.

Prospects for automated diagnosis of verbal autopsies

Verbal autopsy is a method for assessing probable causes of death from lay reporting of signs, symptoms and circumstances by family members or caregivers of a deceased person. Several methods of automated diagnoses of causes of death from standardized verbal autopsy questionnaires have been developed recently (Inter-VA, Tariff, Random Forest and King-Lu). Their performances have been assessed in a series of papers in BMC Medicine. Overall, and despite high specificity, the current strategies of automated computer diagnoses lead to relatively low sensitivity and positive predictive values, even for causes which are expected to be easily assessed by interview. Some methods have even abnormally low sensitivity for selected diseases of public health importance and could probably be improved. Ways to improve the current strategies are proposed: more detailed questionnaires; using more information on disease duration; stratifying for large groups of causes of death by age, sex and main category; using clusters of signs and symptoms rather than quantitative scores or ranking; separating indeterminate causes; imputing unknown cause with appropriate methods.Please see related articles: http://www.biomedcentral.com/1741-7015/12/5; http://www.biomedcentral.com/1741-7015/12/19; http://www.biomedcentral.com/1741-7015/12/20; http://www.biomedcentral.com/1741-7015/12/21; http://www.biomedcentral.com/1741-7015/12/22; http://www.biomedcentral.com/1741-7015/12/23.

Comment: Health transitions and regressions in Southern Africa

Overall, the mortality decline has been impressive in sub-Saharan Africa in the second half of the twentieth century. Life expectancies below 40 years were common before 1950, whereas they could exceed 60 years at the end of the century. This health transition occurred in the context of the development of modern states, of modern public health and hygiene, of health personnel and technology (medicines and vaccines), as well as improving nutrition and levels of education. However, these transitions were not always smooth, and were sometimes halted by major political or economic crises as well as by emerging diseases. Furthermore, major changes in diet and lifestyle could also have a negative impact on mortality trends. The Agincourt case study provides solid evidence on mortality levels and major health problems, as well as positive and negative trends in age-, sex-, and cause-specific death rates since 1992 (see the paper by Kathleen Kahn et al. [1]). Mortality levels at baseline appeared relatively low for a rural area of Africa, with female life expectancy above 70 years and a wide gap between males and females. This level compares with that of Western Europe around 1950 despite lower levels of income. However, several features of cause-specific mortality stand in contrast with European patterns. Mortality from external causes (accidents and violence), from diarrhoeal diseases, from severe malnutrition (kwashiorkor), from maternal causes, and from cancers of the female genital tract was higher than expected at this level of mortality. Severe malnutrition and diarrhoea seemed related to the vulnerability of the poorest strata; maternal mortality with low coverage of maternal care among older women; female cancers with the epidemics of sexually transmitted diseases; accidents (household and road traffic) with the newer dangers of modern life; and violent deaths with the overall pattern in post-apartheid society and the weakness of gun control measures. Beyond the specific features at baseline, mortality trends revealed the new public health challenges of this transitional society. Above all, in just a few years, HIV/AIDS became the leading cause of death among young adults and young children, reversing

Improving completeness of birth and death registration in rural Africa

www.thelancet.com/lancetgh Vol 4 September 2016 e604 the functioning of the registration system. Registration being nearly complete (>90%) implies that all social strata were affected by the changes to registration practice, which can be verified by socioeconomic analysis. For the poorest group (lowest level of wealth), completeness of birth registration increased from 5% in 1992–94 to 67% in 2013–14 (vs 10% to 94% for the wealthiest group), and completeness of death registration increased from 39% to 85% (vs 75% to 100% for the wealthiest group). For the least educated group (primary school education or less), completeness of birth registration increased from 8% in 1992–94 to 81% in 2013–14 (vs 20% to 90% for the most educated group), and completeness of death registration increased from 54% to 92% (vs 57% to 91% for the most educated group). For the former Mozambican refugees, completeness of birth registration increased from 4% in 1992–94 to 77% in 2013–14 (vs 11% to 87% for South Africans), and completeness of death registration increased from 19% to 89% (vs 58% to 95% for South Africans). Completeness of birth registration did not diff er by sex, and women’s deaths were at least as well registered as men’s Improving completeness of birth and death registration in rural Africa