Kenneth Harttgen

Association between economic growth and early childhood undernutrition: evidence from 121 Demographic and Health Surveys from 36 low-income and middle-income countries

BACKGROUND Economic growth is widely regarded as a necessary, and often sufficient, condition for the improvement of population health. We aimed to assess whether macroeconomic growth was associated with reductions in early childhood undernutrition in low-income and middle-income countries. METHODS We analysed data from 121 Demographic and Health Surveys from 36 countries done between Jan 1, 1990, and Dec 31, 2011. The sample consisted of nationally representative cross-sectional surveys of children aged 0-35 months, and the outcome variables were stunting, underweight, and wasting. The main independent variable was per-head gross domestic product (GDP) in constant prices and adjusted for purchasing power parity. We used logistic regression models to estimate the association between changes in per-head GDP and changes in child undernutrition outcomes. Models were adjusted for country fixed effects, survey-year fixed effects, clustering, and demographic and socioeconomic covariates for the child, mother, and household. FINDINGS Sample sizes were 462,854 for stunting, 485,152 for underweight, and 459,538 for wasting. Overall, 35·6% (95% CI 35·4-35·9) of young children were stunted (ranging from 8·7% [7·6-9·7] in Jordan to 51·1% [49·1-53·1] in Niger), 22·7% (22·5-22·9) were underweight (ranging from 1·8% [1·3-2·3] in Jordan to 41·7% [41·1-42·3] in India), and 12·8% (12·6-12·9) were wasted (ranging from 1·2% [0·6-1·8] in Peru to 28·8% [27·5-30·0] in Burkina Faso). At the country level, no association was seen between average changes in the prevalence of child undernutrition outcomes and average growth of per-head GDP. In models adjusted only for country and survey-year fixed effects, a 5% increase in per-head GDP was associated with an odds ratio (OR) of 0·993 (95% CI 0·989-0·995) for stunting, 0·986 (0·982-0·990) for underweight, and 0·984 (0·981-0·986) for wasting. ORs after adjustment for the full set of covariates were 0·996 (0·993-1·000) for stunting, 0·989 (0·985-0·992) for underweight, and 0·983 (0·979-0·986) for wasting. These findings were consistent across various subsamples and for alternative variable specifications. Notably, no association was seen between per-head GDP and undernutrition in young children from the poorest household wealth quintile. ORs for the poorest wealth quintile were 0·997 (0·990-1·004) for stunting, 0·999 (0·991-1·008) for underweight, and 0·991 (0·978-1·004) for wasting. INTERPRETATION A quantitatively very small to null association was seen between increases in per-head GDP and reductions in early childhood undernutrition, emphasising the need for direct health investments to improve the nutritional status of children in low-income and middle-income countries. FUNDING None.

Multilevel structured additive regression

Models with structured additive predictor provide a very broad and rich framework for complex regression modeling. They can deal simultaneously with nonlinear covariate effects and time trends, unit- or cluster-specific heterogeneity, spatial heterogeneity and complex interactions between covariates of different type. In this paper, we propose a hierarchical or multilevel version of regression models with structured additive predictor where the regression coefficients of a particular nonlinear term may obey another regression model with structured additive predictor. In that sense, the model is composed of a hierarchy of complex structured additive regression models. The proposed model may be regarded as an extended version of a multilevel model with nonlinear covariate terms in every level of the hierarchy. The model framework is also the basis for generalized random slope modeling based on multiplicative random effects. Inference is fully Bayesian and based on Markov chain Monte Carlo simulation techniques. We provide an in depth description of several highly efficient sampling schemes that allow to estimate complex models with several hierarchy levels and a large number of observations within a couple of minutes (often even seconds). We demonstrate the practicability of the approach in a complex application on childhood undernutrition with large sample size and three hierarchy levels.

Patterns of Frailty in Older Adults: Comparing Results from Higher and Lower Income Countries Using the Survey of Health, Ageing and Retirement in Europe (SHARE) and the Study on Global AGEing and Adult Health (SAGE)

We use the method of deficit accumulation to describe prevalent and incident levels of frailty in community-dwelling older persons and compare prevalence rates in higher income countries in Europe, to prevalence rates in six lower income countries. Two multi-country data collection efforts, SHARE and SAGE, provide nationally representative samples of adults aged 50 years and older. Forty items were used to construct the frailty index in each data set. Our study shows that the level of frailty was distributed along the socioeconomic gradient in both higher and lower income countries such that those individuals with less education and income were more likely to be frail. Frailty increased with age and women were more likely to be frail in most countries. Across samples we find that the level of frailty was higher in the higher income countries than in the lower income countries.

The association of parental education with childhood undernutrition in low- and middle-income countries: comparing the role of paternal and maternal education.

Abstract Background: Most existing research on the association of parental education with childhood undernutrition focuses on maternal education and often ignores paternal education. We systematically investigate differences in maternal and paternal education and their association with childhood undernutrition. Methods: One hundred and eighty Demographic and Health Surveys from 62 countries performed between 1990 and 2014 were analysed. We used linear-probability models to predict childhood undernutrition prevalences, measured as stunting, underweight and wasting, for all combinations of maternal and paternal attainment in school. Models were adjusted for demographic and socio-economic covariates for the child, mother and household, country-level fixed effects and clustering. Additional specifications adjust for local area characteristics instead of country fixed effects. Results: Both higher maternal and paternal education levels are associated with lower childhood undernutrition. In regressions adjusted for child age and sex as well as country-level fixed effects, the association is stronger for maternal education than for paternal education when their combined level of education is held constant. In the fully adjusted models, the observed differences in predicted undernutrition prevalences are strongly attenuated, suggesting a similar importance of maternal and paternal education. These findings are confirmed by the analysis of composite schooling indicators. Conclusions: We find that paternal education is similarly important for reducing childhood undernutrition as maternal education and should therefore receive increased attention in the literature.

A Reversal in the Relationship of Human Development with Fertility

Myrskylä et al. (2009) found that the relationship between the human development index (HDI) and the total fertility rate (TFR) reverses from negative (i.e., increases in HDI are associated with decreases in TFR) to positive (i.e., increases in HDI are associated with increases in TFR) at an HDI level of 0.86. In this article, we show that the reversal in the HDI-TFR relationship is robust to neither the UNDP’s recent revision in the HDI calculation method nor thedecomposition of the HDI into its education, standard-of-living, and health subindices.

Prevalence of and factors associated with frailty and disability in older adults from China, Ghana, India, Mexico, Russia and South Africa

BACKGROUND The severe burden imposed by frailty and disability in old age is a major challenge for healthcare systems in low- and middle-income countries alike. The current study aimed to provide estimates of the prevalence of frailty and disability in older adult populations and to examine their relationship with socioeconomic factors in six countries. METHODS Focusing on adults aged 50+ years, a frailty index was constructed as the proportion of deficits in 40 variables, and disability was assessed using the World Health Organization Disability Assessment Schedule (WHODAS 2.0), as part of the Study on global AGEing and adult health (SAGE) Wave 1 in China, Ghana, India, Mexico, Russia and South Africa. RESULTS This study included a total of 34,123 respondents. China had the lowest percentages of older adults with frailty (13.1%) and with disability (69.6%), whereas India had the highest percentages (55.5% and 93.3%, respectively). Both frailty and disability increased with age for all countries, and were more frequent in women, although the sex gap varied across countries. Lower levels of both frailty and disability were observed at higher levels of education and wealth. Both education and income were protective factors for frailty and disability in China, India and Russia, whereas only income was protective in Mexico, and only education in South Africa. CONCLUSIONS Age-related frailty and disability are increasing concerns for older adult populations in low- and middle-income countries. The results indicate that lower levels of frailty and disability can be achieved for older people, and the study highlights the need for targeted preventive approaches and support programs.

Do Fragile Countries Experience Worse MDG Progress

Abstract While it is regularly stated that development progress in so-called fragile states is lagging behind, only very limited empirical analysis exists that investigates to what extent the levels and trends in achievements in MDG indicators differ between fragile and other developing countries, and between different definitions of fragile states. We analyse levels of MDG indicators and progress towards achieving the MDGs between 1990 and 2008 of fragile and non-fragile countries. We focus particularly on the widely used World Bank approach to define fragility, but also compare it with other definitions. We show that fragile countries are, indeed, performing worse in terms of achievement levels of MDG indicators. However, progress in these measures is, on average, not slower in fragile states using most definitions of fragility, and highly heterogeneous among the both fragile and non-fragile countries; only if fragility is defined very narrowly do we see lower progress towards the MDGs. As a result, we suggest that current definitions of fragility are not useful aggregations to predict, monitor and explain development progress using MDG indicators.

Desired Fertility and Number of Children Born Across Time and Space

Economists have often argued that high fertility rates are mainly driven by women’s demand for children (and not by family planning efforts) with low levels of unwanted fertility across countries (and hence with little room for family planning efforts to reduce population growth). We study the relationship between wanted fertility and number of children born in a panel of 200 country-years controlling for country fixed effects and global time trends. In general, we find a close relationship between wanted and actual fertility, with one desired child leading to one additional birth. However, our results also indicate that in the last 20 years, the level of unwanted births has stayed at 2 across African countries but has, on average, decreased from 1 to close to 0 in other developing countries. Hence, women in African countries are less able to translate child preferences into birth outcomes than women in other developing countries, and forces other than fertility demand have been important for previous fertility declines in many developing countries. Family planning efforts only partially explain the observed temporal and spatial differences in achieving desired fertility levels.

Association between economic growth and early childhood nutrition – Authors' reply

Background Economic growth is widely regarded as a necessary, and often sufficient, condition for the improvement of population health. We aimed to assess whether macroeconomic growth was associated with reductions in early childhood undernutrition in low-income and middle-income countries. Methods We analysed data from 121 Demographic and Health Surveys from 36 countries done between Jan 1, 1990, and Dec 31, 2011. The sample consisted of nationally representative cross-sectional surveys of children aged 0-35 months, and the outcome variables were stunting, underweight, and wasting. The main independent variable was per-head gross domestic product (GDP) in constant prices and adjusted for purchasing power parity. We used logistic regression models to estimate the association between changes in per-head GDP and changes in child undernutrition outcomes. Models were adjusted for country fixed effects, survey-year fixed effects, clustering, and demographic and socioeconomic covariates for the child, mother, and household. Findings Sample sizes were 462 854 for stunting, 485 152 for underweight, and 459 538 for wasting. Overall, 35.6% (95% CI 35.4-35.9) of young children were stunted (ranging from 8.7% [7.6-9.7] in Jordan to 51.1% [49.1-53.1] in Niger), 22.7% (22.5-22.9) were underweight (ranging from 1.8% [1.3-2.3] in Jordan to 41.7% [41.1-42.3] in India), and 12.8% (12.6-12.9) were wasted (ranging from 1.2% [0.6-1.8] in Peru to 28.8% [27.5-30.0] in Burkina Faso). At the country level, no association was seen between average changes in the prevalence of child undernutrition outcomes and average growth of per-head GDP. In models adjusted only for country and survey-year fixed effects, a 5% increase in per-head GDP was associated with an odds ratio (OR) of 0.993 (95% CI 0.989-0.995) for stunting, 0.986 (0.982-0.990) for underweight, and 0.984 (0.981-0.986) for wasting. ORs after adjustment for the full set of covariates were 0.996 (0.993-1.000) for stunting, 0.989 (0.985-0.992) for underweight, and 0.983 (0.979-0.986) for wasting. These findings were consistent across various subsamples and for alternative variable specifications. Notably, no association was seen between per-head GDP and undernutrition in young children from the poorest household wealth quintile. ORs for the poorest wealth quintile were 0.997 (0.990-1.004) for stunting, 0.999 (0.991-1.008) for underweight, and 0.991 (0.978-1.004) for wasting. Interpretation A quantitatively very small to null association was seen between increases in per-head GDP and reductions in early childhood undernutrition, emphasising the need for direct health investments to improve the nutritional status of children in low-income and middle-income countries.

HIV surveys in older adults : better data, better health

Most nationally representative HIV surveys, including those of the Demographic and Health Surveys Programme, limit eligibility for HIV testing to adults younger than 50 years or 55 years of age. These age limits refl ect the belief that HIV is a disease acquired in youth and with con sequences in middle age. However, as the epidemic evolves, information about HIV in older people will become essential, and age limits for surveys should be removed for six reasons. First, the epidemic is ageing. The worldwide expansion of antiretroviral therapy (ART) coverage, with an estimated 13·6 million people receiving treatment in 2014, has substantially increased the life expectancy of adults with HIV, leading to rapidly increasing numbers of HIV-infected older adults. The age distribution of HIV prevalence is changing: the peak is moving to older ages and the decline beyond the peak is becoming fl atter. About 4·2 million people aged 50 years and older are living with HIV, and this number is expected to increase substantially over the coming decades, in particular in sub-Saharan Africa. Second, the long-term health, economic, and social outcomes of ART in older people are crucial for the success of future intervention strategies, but they have never been quantifi ed. Adults who have lived with HIV and have been taking ART for long periods are expected to be at increased risk of non-communicable diseases (NCDs). The increase in life expectancy provided by ART in this population will unmask the burden of other diseases previously hidden by high HIV-related mortality. Moreover, many antiretroviral drugs have side-eff ects that are important risk factors for NCDs, such as diabetes and cardiovascular disease. Finally, despite eff ective ART, HIV-infected adults have persistent HIV-associated infl ammation, leading to accelerated ageing and increased incidence of NCDs. Third, it has commonly been assumed that older adults are not at risk of acquiring HIV; however, evidence on sexual behaviour and HIV incidence across the life course suggests that this assumption is false. Determinants of HIV acquisition in older adults quite likely diff er substantially from those in younger adults. Some risk factors (such as divorce or death of a partner), might only play a part in older adults, whereas others (such as lack of HIV knowledge and failure to adopt preventive behaviours) may be relevant across all ages but increase in importance with age. Fourth, a key question that can be answered only if HIV surveys include older adults is what sets individuals who survive HIV-free into old age apart from those who acquire HIV at some point during their lifetime— lifelong individual characteristics, age-dependent risk factors (such as sexual behaviours, marriage, fertility and contraception), or chance? Fifth, older adults have important roles in HIVaff ected households, and how they fulfi l these roles will likely depend on their own HIV status. The HIV epidemic has had substantial eff ects on household structures and roles, in particular in sub-Saharan Africa. For instance, skip-generation households in which grandparents care for grand children are one of the consequences of the age course of HIV infection. The ageing of the HIV epidemic will probably change the roles of older adults in households in high HIV prevalence communities, as HIV-infected middle-aged adults remain alive and grow old on ART. Sixth, the off ering of HIV testing to older adults in population-based HIV surveys might increase HIV testing rates. The exclusion of older adults from HIV surveys is likely to have increased the exceptional and stigmatised nature of HIV infection. Moreover, older adults in many societies are highly respected and their behaviour socially sanctions and encourages similar behaviour. HIV testing among older adults might therefore have positive spillover eff ects on testing rates in younger people. Inclusion of older adults in HIV surveys will provide a historic opportunity to establish the eff ects of large-scale ART and the ageing of the HIV epidemic on health, economic, and social outcomes. Data on HIV infections in older adults will enable the research needed for providing a sound empirical foundation for the designing and planning of future HIV prevention, treatment, and care strategies.