Growth faltering in rural Gambian children after four decades of interventions: a retrospective cohort study
Summary of Research1
Nabwera HM, Fulford AJ, Moore SE and Prentice AM. (2017). Growth faltering in rural Gambian children after four decades of interventions: a retrospective cohort study. The Lancet Global Health, Volume 5, No.2, e208-e216, February 2017. Available open access at: http://thelancet.com/journals/langlo/
Location: Gambia
What we know: Growth faltering remains common in children in sub-Saharan Africa; factors to alleviate this remain poorly understood, limiting intervention design.
What this article adds: A retrospective cohort study using routine growth-monitoring data for children under two years assessed trends in growth faltering in rural Gambia over four decades. Those studied received unprecedented investments in healthcare and nutrition-related infrastructure. Over 40 years, underweight or stunting proportions at two years of age halved and growth parameters improved. However, prevalence of low birthweight (12%), childhood stunting (30%), and underweight (22%) remained high. Wasting prevalence did not change and growth faltering between three months and 21 months was only marginally attenuated. A high threshold for water, sanitation and hygiene (WASH) improvements is likely necessary to impact growth faltering; environmental enteropathy may provide a missing link. More understanding is needed of missing contributors to growth faltering to guide development of new interventions.
Growth faltering remains common in children in sub-Saharan Africa and is associated with substantial morbidity and mortality. Rates of stunting have been declining, but there are still 159 million stunted children worldwide (WHO, 2017). The prevalence of stunting has declined most slowly in sub-Saharan Africa and the absolute number of children with stunting has increased due to population growth (WHO, 2017). Key elements of progress that alleviate growth faltering are poorly understood, thus limiting the design of interventions and the targeting of health and development inputs.
A retrospective cohort study was carried out using routine growth-monitoring data for all children whose date of birth had been recorded to assess trends in growth faltering in children younger than two years in the West Kiang region of Gambia during the past four decades. Three rural villages in the region (Keneba, Manduar and Kantong Kunda) have benefited from free healthcare provided by the UK Medical Research Council (MRC) for the past 40 years. Since the 1970s, there have been increasing levels of support and interventions such that these villages have benefited from unprecedented levels of nutrition-specific and nutrition-sensitive interventions compared with other such communities in rural, low-income settings.
Routine growth data from birth to two years of age were available for 3,659 children between 1976 and 2012. Z scores for weight-for-age (WAZ), length-for-age (LAZ), weight-for-length (WLZ), mid-upper-arm circumference (MUAC) and head circumference (HC) were calculated using the WHO 2006 growth standards. Seasonal patterns of mean Z scores were obtained by Fourier regression. Growth faltering was defined as fall in Z score between three months and 21 months of age.
Results
Results reveal secular improvements in all postnatal growth parameters (except weight-for-length), accompanied by declines over time in seasonal variability. The proportion of children with underweight or stunting at two years of age halved during four decades of the study period, from 38·7% (95% CI 33·5–44·0) to 22·1% (19·4 to 24·8) for underweight and 57·1% (51·9–62·4) to 30·0%, (27·0–33·0) for stunting. However, prevalence remained unacceptably high. Postnatal growth faltering also persisted, leading to poor nutritional status at 24 months (LAZ −1·36, 95% CI −1·44 to −1·27, WAZ −1·20, −1·28 to −1·11, and HC Z score −0·51, −0·59 to −0·43). These infants characteristically were born small and continued to fall away from the WHO standard length centiles throughout the first two years of life, despite weight showing early catch-up while the infants were still fully breastfed and largely protected from infections (the trend for which is magnified in their WLZ due to simultaneous decline in length). MUAC and head circumference were similarly resilient. Growth failure is markedly seasonal in this environment, with greater deficits occurring in the rainy season. The incidence of diarrhoea, malaria and bronchiolitis in the children younger than 12 months fell by 80% during the four decades studied, while the incidence of pneumonia seemed to increase.
Discussion
During almost four decades, the MRC has made sustained investments in healthcare and nutrition-related infrastructure in the core study villages; these inputs are unparalleled across rural Africa and would be prohibitively expensive for governments of low-income countries to roll out nationwide. These villages have access to antenatal and postnatal care and round-the-clock access to clinicians and nurses in a well-equipped and efficient primary healthcare clinic. All health services are free of charge. All children are fully vaccinated, receive vitamin A, mebendazole and other health interventions as per WHO protocols. Breastfeeding rates are among the best worldwide and are further supported by baby-friendly community initiatives, accompanied by regular messaging in support of exclusive breastfeeding for six months.
Open defecation and water obtained from contaminated open wells have been universally replaced by latrines in all compounds and tube well water supplied through clean pipes to standpipes around the villages. Studies have shown that these interventions have had a profound effect on mortality in children under five years old (Rayco-Solon et al, 2004) and the incidence of most diseases, especially diarrhoea, which has previously been implicated as a major cause of growth failure (Poskitt et al, 1999).
In addition, children attend regular well-baby checks with growth monitoring and a dedicated treatment centre for severely malnourished children is provided to treat those who do become malnourished. The remittance economy from village members who have migrated overseas, together with incomes from employment at the MRC, have greatly improved food security and attenuated the stress of the so-called hungry season, as reflected in the reduction in the amplitude of seasonal growth faltering in the region. This increased wealth has also improved housing conditions and dispersed families over a wider area, reducing overcrowding. Child mortality has fallen, birth spacing has increased and family size has decreased.
Despite the unprecedented levels of investment, the prevalence of low birthweight (12%), childhood stunting (30%), and underweight (22%) remains high. The prevalence of wasting has not changed and growth faltering between three months and 21 months has only been marginally attenuated. These data suggest that the refractory stunting must be caused by factors beyond the improvements and interventions provided in the study villages. Environmental enteropathy affecting almost all children in low-income settings has been proposed as the mechanism linking growth failure with WASH (water, sanitation and hygiene) deficits (Dangour et al, 2013). Results suggest that there is a very high threshold for WASH improvements that must be achieved before growth faltering can be eliminated. Improved housing conditions, including piped water, might be a necessary step. More understanding is needed of the missing contributors to growth faltering to guide development of new interventions.
A comment on this study is also published in the same issue. Crane, R. J. and Berkley, J.A. (2017) Progress on growth faltering. The Lancet Global Health, Volume 5, No.2, e125-e126, February, 2017. Available open access at: http://thelancet.com/journals/langlo/
References
Dangour AD, Watson L, Cumming O, et al. Interventions to improve water quality and supply, sanitation and hygiene practices, and their effects on the nutritional status of children. Cochrane Database Syst Rev 2013; 8: CD009382.
Poskitt EM, Cole TJ and Whitehead RG. Less diarrhoea but no change in growth: 15 years’ data from three Gambian villages. Arch Dis Child 1999; 80: 115–19.
Rayco-Solon P, Moore SE, Fulford AJ and Prentice AM. Fifty-year mortality trends in three rural African villages. Trop Med Int Health 2004; 9: 1151–60.
WHO Global Nutrition Targets 2025. www.who.int/nutrition/publications/globaltargets2025_policybrief_overview/en/ (accessed Jan 2, 2017).
More like this
FEX: Wasting and Stunting Technical Interest Group (WaSt TIG) meeting
On the 15th of January 2018 the Wasting and Stunting (WaSt) Technical Interest Group (TIG) held their third face-to-face meeting at Trinity College, Oxford. This group of 30...
FEX: The relationship between wasting and stunting: a retrospective cohort analysis of longitudinal data in Gambian children from 1976 to 2016
View this article as a pdf Summary of research1 Location: Gambia What we know: There are gaps in understanding the relationship between wasting and stunting that often...
FEX: The Wasting-Stunting Technical Interest Group: Summarising the work to date
This is a summary of a Field Exchange field article that was included in issue 67. The original article was authored by Natalie Sessions and Tanya Khara. Natalie Sessions is a...
FEX: MUAC vs WHZ in predicting mortality in hospitalised children under five years of age
Summary of research1 This research contributes to the evidence base regarding which anthropometric indicators identify malnourished sick children most at risk of death. Low...
FEX: Effect of a community-led sanitation intervention on child diarrhoea and child growth in rural Mali
Summary of research1 Location: Mali What we know: Community-led total sanitation (CLTS) is being scaled up, but there is limited evidence on child health impacts. What this...
FEX: The Wasting-Stunting Technical Interest Group: A summary of the work to date
View this article as a pdf Lisez cet article en français ici This article outlines the work of the Wasting-Stunting Technical Interest Group since its inception in...
WaSt TIG - the work so far
We have had three phases of work thus far and are currently in the fourth. A special section in FEX summarises a lot of the work of the WaSt TIG so far as well as experiences...
Resource: The relationship between wasting and stunting: a retrospective cohort analysis of longitudinal data in Gambian children from 1976 to 2016
Abstract Background: The etiologic relationship between wasting and stunting is poorly understood, largely because of a lack of highquality longitudinal data from children at...
FEX: Relationships between wasting and stunting and their concurrent occurrence in Ghanaian pre-school children
Summary of research* Location: Ghana. What we know: Wasting is a short-term health issue, but repeated episodes may lead to stunting (long-term or chronic malnutrition). This...
FEX: Improving screening for malnourished children at high risk of death
Research snapshot1 The purpose of this study was to investigate whether children with concurrent wasting and stunting (WaSt) require therapeutic feeding and to better...
FEX: Supporting healthy growth in infants in low-resource settings in Mumbai, India
View this article as a pdf Lisez cet article en français ici By Rupal Dalal, Shruthi Iyer, Marian Abraham and Lahari Yaddanapudi Rupal Dalal MD FAAP IBCLC is a...
FEX: Does economic growth reduce childhood undernutrition in Ethiopia?
Summary of research1 Location: Ethiopia What we know: Rapid economic growth in developing countries has had a mixed effect on human development; the impact on reducing...
FEX: Research snapshots
Factors influencing pastoral and agropastoral household vulnerability to food insecurity in Kenya Kenya has a population of more than 38 million, 10% of whom are classified as...
en-net: Despite having worse wasting level and similar stunting level, why South Asia have less under five mortality than Sub Saharan Africa?
Some background (all WHO 2016 data, Economy data World Bank): Mortality Based on WHO's rank of under-five mortality African countries make the lowest 19 countries with...
Resource: Changing sex differences in undernutrition of African children: findings from Demographic and Health Surveys
Abstract The study investigates sex differences in the prevalence of undernutrition in sub-Saharan Africa. Undernutrition was defined by Z-scores using the CDC-2000 growth...
Other meetings
ENN initiates meetings where there are important gaps related to policy, programming and research and organises meetings where ENN coordinates long term technical projects....
FEX: Effectiveness of a community-based infant and young child feeding support group programme among ethnic minorities in Vietnam
By Md Masud Rana, Huan Nguyen Van and Thach Nguyen Ngoc View this article as a pdf Md Masud Rana is a Nutrition Advisor with Save the Children with a particular focus on...
Wasting and Stunting-making progress on understanding the links
Friday 16th February, 2017 By Carmel Dolan, ENN Technical Director Some of you will know that ENN has been coordinating a project with the expert steer of around 30 child...
Blog post: Wasting and Stunting-making progress on understanding the links
Some of you will know that ENN has been coordinating a project with the expert steer of around 30 child growth and nutrition specialists from academia, donor and operational...
FEX: Preventing and treating growth faltering in Maya children
Research snapshot1 The Maya people are descended from the indigenous inhabitants of southern Mexico, Guatemala and adjacent regions of Central America. In Guatemala, 50% of...
Reference this page
Growth faltering in rural Gambian children after four decades of interventions: a retrospective cohort study. Field Exchange 54, February 2017. p24. www.ennonline.net/fex/54/growthfalteringgambiacohort
(ENN_5505)