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 Senior Nutritionist at ENN

Tanya Khara is a Technical Director at ENN

Key messages:

• This article outlines the work of the Wasting-Stunting Technical Interest Group (WaSt-TIG) since its inception in 2014.
• Important research has been undertaken by the project, focusing on the complex relationship between wasting and stunting, as well as the implications of their continued separation in policy, programmes and research.
• Future priorities for the WaSt-TIG include further articulation of the programme and policy implications.

Background

Over recent decades, child wasting and stunting have been conceptualised and addressed separately resulting in different policies, programmes, research and financing mechanisms. During emergencies, programmes have focused on the short-term treatment of wasted children and the prevention of deaths. In development programmes, the focus has been on the longer-term prevention of stunting and micronutrient deficits. This is despite the fact that wasting and stunting co-occur in humanitarian and development contexts.

In 2014, ENN began exploring the relationship between wasting and stunting to assess whether the separation was justified. The Wasting-Stunting Technical Interest Group (WaSt-TIG) was set up, including 42 expert researchers, programmers and donors in the fields of child growth, nutrition and epidemiology. Since 2014, the work of the WaSt TIG has evolved from reviewing existing evidence and defining research gaps to mining existing data, communicating learnings and exploring the implications for policy and practice. 

Reviewing existing evidence and defining research gaps  

• The WaSt TIG developed a narrative review of the available literature on the relationship between wasting and stunting.¹ This review explored the shared causes and effects of wasting and stunting, examined the patterns of association and physiological mechanisms and reflected on potential policy and programmatic implications. Even then, it was clear that wasting and stunting shared closer links than commonly recognised with children who experienced both deficits being at a disproportionally higher risk of mortality.
• Based on the identified gaps, a research prioritisation exercise was undertaken to guide future research investments (Angood et al, 2016). This provided clear priorities for the WaSt TIG’s workplan.
• Several research questions were answerable through further analysis of existing datasets. Two questions were viewed as relatively straightforward to answer: (1) ‘What more can cross-sectional data tell us about the factors associated with childhood wasting and stunting and concurrence?’ and (2) ‘How does concurrent wasting and stunting develop over time?’.
• Following a request by the independent expert group leading the 2015 Global Nutrition Report, a short analysis of national surveys from five high-burden countries was conducted to estimate the burden of concurrent wasting and stunting. The findings suggested that around 16 million children globally are wasted and stunted at the same time.  

Mining existing data

• The WaSt-TIG expanded the above analysis using Demographic and Health Survey and Multiple Indicator Cluster Survey datasets from 84 countries. For the first time, a pooled prevalence estimate for the burden of concurrent wasting and stunting was generated at 3.0% (95% CI: 2.97, 3.06) and was published in the 2016 Global Nutrition Report.
• Findings from an analysis of Standardized Monitoring and Assessment of Relief and Transitions survey data from 51 countries further showed that younger children (<36 months of age) and males were more likely to experience concurrent wasting and stunting (Myatt et al, 2018).
• Using cohort data from Niakhar in Senegal (Garenne et al, 2019), the WaSt-TIG then explored the implications of concurrent wasting and stunting. This analysis reiterated that concurrent wasting and stunting was a strong risk factor for child mortality. It also identified a combination of severely low weight-for-age z-scores and mid-upper arm circumference as the best identifier of children most at risk of dying, including those concurrently wasted and stunted.
• A concept note was then developed for a cohort study examining the relationship between stunting and wasting, and their combined effect on mortality, in existing programme practices. This concept note secured funding from the United States Agency of International Development’s Bureau for Humanitarian Assistance.
• At the same time, a separate analysis began of cohort data from the Medical Research Council (MRC) Gambia surveillance programme exploring how children experience wasting and stunting over time.

Delving deeper

• The analysis of the MRC surveillance data replicated earlier findings that being wasted was predictive of stunting three months later (Schoenbuchner et al, 2019). It also showed that, compared to non-stunted children, those who became stunted at two years of age had previously experienced more wasting.
• Seasonal patterns for wasting were noted in the cohort analysis. Specifically, infants born at the start of the wet season showed early growth faltering and an increased risk of subsequent stunting.

Communicating learnings

• Given the emerging evidence, the WaSt-TIG started asking ‘So what?’. As a result, a policy brief² was developed to outline the scientific grounds for challenging the separation of wasting and stunting in policy, programmes and research.
• The policy brief called for a radical change in how child wasting and stunting are viewed, financed and addressed. This was expanded in a viewpoint article published in The Lancet Child and Adolescent Health.³
• The work of the WaSt TIG was evaluated using a ‘Story of Change’ method.⁴ Project successes were attributed to the way the WaSt-TIG operates, namely being made up of individual expert members who represent themselves rather than their institution’s agenda and who function in an engaged, iterative, exploratory and task-orientated manner.
• Several achievements of the project were identified, including: (1) contributing to a solid evidence base describing the linkages between wasting and stunting; (2) promoting discussions around wasting and stunting and a shift in the narrative around how to address these globally; and (3) helping to bridge the divide between the wasting and stunting communities.

Implications for policy and practice

• In 2020, the WaSt-TIG entered its fourth phase of work. This phase has included an expanded analysis of anthropometric measures and mortality risk, an updated systematic review on the relationship between wasting and stunting, a systematic review and meta-analysis exploring sex differences in undernutrition and a briefing note for policymakers and programme implementers on the ‘best practices in preventing child wasting within the wider context of undernutrition’.

Conclusion

The WaSt-TIG has brought researchers together with policy developers and nutrition programme staff to discuss how research can be used to improve our understanding of undernutrition, its consequences for children’s growth and how to prevent it. While much has been achieved, more work is needed to further articulate the programme and policy implications. Some exciting next steps include a focus on dissemination and advocacy, translating evidence into practice, expanding to other settings at country and regional levels and further exploring the evidence.  

References

Angood C, Khara T, Dolan C, Berkley J, WaSt Technical Interest Group (2016) Research Priorities on the Relationship between Wasting and Stunting. PLoS ONE 11, 5.

Garenne M, Myatt M, Khara T, Dolan C, Briend A (2019) Concurrent wasting and stunting among under-five children in Niakhar, Senegal. Maternal and Child Nutrition, 2019, 15, 2, e12736.

Myatt M, Khara T, Schoenbuchner S, Pietzsch S, Dolan C, Lelijveld N et al (2018) Children who are both wasted and stunted are also underweight and have a high risk of death: a descriptive epidemiology of multiple anthropometric deficits using data from 51 countries. Archives of Public Health, 76, 28.

Schoenbuchner S, Dolan C, Mwangome M, Hall A, Richard S, Wells J et al (2019) The relationship between wasting and stunting: a retrospective cohort analysis of longitudinal data in Gambian children from 1976 to 2016. American Journal of Clinical Nutrition, 110, 498–507.