Neurodevelopmental, cognitive, behavioural and mental health impairments following childhood malnutrition: a systematic review

Abstract

Background: Severe childhood malnutrition impairs growth and development short-term, but current understanding of long-term outcomes is limited. We aimed to identify studies assessing neurodevelopmental, cognitive, behavioural and mental health outcomes following childhood malnutrition. Methods: We systematically searched MEDLINE, EMBASE, Global Health and PsychINFO for studies assessing these outcomes in those exposed to childhood malnutrition in low- and middle-income settings. We included studies assessing undernutrition measured by low mid-upper arm circumference, weight-for-height, weight-for-age or nutritional oedema. We used guidelines for synthesis of results without meta-analysis to analyse three outcome areas: neurodevelopment, cognition/academic achievement, behaviour/mental health. Results: We identified 30 studies, including some long-term cohorts reporting outcomes through to adulthood. There is strong evidence that malnutrition in childhood negatively impacts neurodevelopment based on high-quality studies using validated neurodevelopmental assessment tools. There is also strong evidence that malnutrition impairs academic achievement with agreement across seven studies investigating this outcome. 8 of 11 studies showed association between childhood malnutrition and impaired cognition. This moderate evidence is limited by some studies failing to measure important confounders such as socioeconomic status. 5 of 7 studies found a difference in behavioural assessment scores in those exposed to childhood malnutrition compared to controls but this moderate evidence is similarly limited by unmeasured confounders. Mental health impacts were difficult to ascertain due to few studies with mixed results. Conclusions: Childhood malnutrition is associated with impaired neurodevelopment, academic achievement, cognition and behavioural problems but evidence regarding possible mental health impacts is inconclusive. Future research should explore the interplay of childhood and later-life adversities on these outcomes. Whilst evidence on improving nutritional and clinical therapies to reduce long-term risks is also needed, preventing and eliminating child malnutrition is likely to be the best way of preventing long-term neurocognitive harms. PROSPERO registration number: CRD42021260498

Evidence of chronic undernutrition in late 19th century German infants of all social classes

“…Camerer's article is of particular interest when considering the modern perception of a pivotal role of nutrition for optimum brain development (Cusick and (Matonti et al, 2020). Generalizing statements such as "Childhood malnutrition is associated with impaired neurodevelopment, academic achievement, cognition and behavioral problems" (Kirolos et al, 2022) and "Macronutrient (protein, fat, glucose) sufficiency is essential for normal brain development. Early macronutrient undernutrition is associated with lower IQ scores, reduced school success, and more behavioral dysregulation" (Schwarzenberg et al, 2018), thus, appear inappropriate and may prompt false decisions in public health and clinical policies.…”

Cost-effectiveness of monthly follow-up for the treatment of uncomplicated severe acute malnutrition: An economic evaluation of a randomized controlled trial

“…While it is unlikely that assessing outcomes over a longer time period would change study findings in a major way, doing so would capture any ongoing health effects or differences in healthcare utilization beyond the intervention period. Recent systematic reviews [4,5] have demonstrated poorer long-term outcomes among children surviving SAM compared to those without a history of SAM, suggesting that more effective SAM treatment may ameliorate these long-term effects. Thirdly, it is possible that the present analysis did not fully capture all benefits of the reduced number outpatient consultations for SAM treatment achieved by the monthly follow-up approach.…”

“…Severe acute malnutrition (SAM)-characterized by weight-for-height <3 standard deviations below WHO growth standards, mid-upper arm circumference (MUAC) <115mm, and/or nutritional oedema-represents a significant fraction of malnutrition-related deaths and a major mortality risk for affected children [3]. Children surviving SAM experience higher rates of morbidity, mortality, and other adverse outcomes later in life [4,5]. In 2020, an estimated 13.6 (10.6, 16.7) million children under 5 developed SAM [6].…”

Exposure to the 1959-1961 Chinese Famine and Risk of Non-Communicable Diseases in Later Life: a Life Course Perspective

“…Existing literature suggests that undernutrition in childhood not only has immediate detrimental health consequences, but also has long-term adverse health consequences 5 , including increasing the risk of NCDs in later life 6 . Such long-term sequelae can be explained by both biological and socioeconomic pathways.…”