Effect of nutrition survey 'cleaning criteria' on estimates of malnutrition prevalence and disease burden: secondary data analysis.

Tackling childhood malnutrition is a global health priority. A key indicator is the estimated prevalence of malnutrition, measured by nutrition surveys. Most aspects of survey design are standardised, but data 'cleaning criteria' are not. These aim to exclude extreme values which may represent measurement or data-entry errors. The effect of different cleaning criteria on malnutrition prevalence estimates was unknown. We applied five commonly used data cleaning criteria (WHO 2006; EPI-Info; WHO 1995 fixed; WHO 1995 flexible; SMART) to 21 national Demographic and Health Survey datasets. These included a total of 163,228 children, aged 6-59 months. We focused on wasting (low weight-for-height), a key indicator for treatment programmes. Choice of cleaning criteria had a marked effect: SMART were least inclusive, resulting in the lowest reported malnutrition prevalence, while WHO 2006 were most inclusive, resulting in the highest. Across the 21 countries, the proportion of records excluded was 3 to 5 times greater when using SMART compared to WHO 2006 criteria, resulting in differences in the estimated prevalence of total wasting of between 0.5 and 3.8%, and differences in severe wasting of 0.4-3.9%. The magnitude of difference was associated with the standard deviation of the survey sample, a statistic that can reflect both population heterogeneity and data quality. Using these results to estimate case-loads for treatment programmes resulted in large differences for all countries. Wasting prevalence and caseload estimations are strongly influenced by choice of cleaning criterion. Because key policy and programming decisions depend on these statistics, variations in analytical practice could lead to inconsistent and potentially inappropriate implementation of malnutrition treatment programmes. We therefore call for mandatory reporting of cleaning criteria use so that results can be compared and interpreted appropriately. International consensus is urgently needed regarding choice of criteria to improve the comparability of nutrition survey data

Omitting edema measurement: how much acute malnutrition are we missing?

BACKGROUND: Acute malnutrition is a major public health issue in low-income countries. It includes both wasting and edematous malnutrition, but the terms wasting and acute malnutrition are often used interchangeably. Little is known about the burden of edematous malnutrition, and few large-scale surveys measure it. OBJECTIVE: Most acute malnutrition might be captured by the measurement of wasting alone, but this is unknown. This article aims to fill this gap. DESIGN: This article presents a secondary data analysis of 852 nutrition cross-sectional survey data sets of children aged 6-59 mo. The data sets assembled included surveys from East, West, South, and Central Africa; the Caribbean; and Asia. The overlap between edematous malnutrition and wasting was assessed, and the impact of including/excluding edema on acute malnutrition prevalence estimates was evaluated. RESULTS: The prevalence of edematous malnutrition varied from 0% to 32.9%, and children were more likely to have bilateral edema in Central and South Africa (OR: 4; 95% CI: 2.8, 5.6). A large proportion of children with edematous malnutrition were not wasted [62% and 66% based on midupper arm circumference (MUAC) and weight-for-height (WFH), respectively], and most were not severely wasted (83% and 86% based on MUAC and WFH, respectively). When wasting and global acute malnutrition prevalence estimates as well as severe wasting and severe acute malnutrition prevalence estimates overall were compared, the differences between estimates were small (median of 0.0% and mean of 0.3% based on WFH and MUAC for global estimates and slightly higher median of 0.1% and mean of 0.4% based on MUAC and WFH, respectively, for the severe forms), but the picture was different at the regional level. CONCLUSIONS: The terms acute malnutrition and wasting should not be used interchangeably. The omission of the measurement of edema can have important repercussions, especially at the nutrition program level

Improving the management of severe acute malnutrition in an area of high HIV prevalence.

AIM: To assess the clinical outcomes of a combined approach to the treatment of severe acute malnutrition in an area of high HIV prevalence using: (i) an initial inpatient phase, based on WHO guidelines and (ii) an outpatient recovery phase using ready-to-use therapeutic food. METHODS: An operational prospective cohort study implemented in a referral hospital in Southern Malawi between May 2003 and 2004. Patient outcomes were compared with international standards and with audits carried out during the year preceding the study. RESULTS: Inpatient mortality was 18% compared to 29% the previous year. Programme recovery rate was 58.1% compared to 45% the previous year. The overall programme mortality rate was 25.7%. Of the total known HIV seropositive children, 49.5% died. CONCLUSIONS: Inpatient mortality and cure rates improved compared to pre-study data but the overall mortality rate did not meet international standards. Additional interventions will be needed if these standards are to be achieved

Is Middle-Upper Arm Circumference "normally" distributed? Secondary data analysis of 852 nutrition surveys.

BACKGROUND: Wasting is a major public health issue throughout the developing world. Out of the 6.9 million estimated deaths among children under five annually, over 800,000 deaths (11.6 %) are attributed to wasting. Wasting is quantified as low Weight-For-Height (WFH) and/or low Mid-Upper Arm Circumference (MUAC) (since 2005). Many statistical procedures are based on the assumption that the data used are normally distributed. Analyses have been conducted on the distribution of WFH but there are no equivalent studies on the distribution of MUAC. METHODS: This secondary data analysis assesses the normality of the MUAC distributions of 852 nutrition cross-sectional survey datasets of children from 6 to 59 months old and examines different approaches to normalise "non-normal" distributions. RESULTS: The distribution of MUAC showed no departure from a normal distribution in 319 (37.7 %) distributions using the Shapiro-Wilk test. Out of the 533 surveys showing departure from a normal distribution, 183 (34.3 %) were skewed (D'Agostino test) and 196 (36.8 %) had a kurtosis different to the one observed in the normal distribution (Anscombe-Glynn test). Testing for normality can be sensitive to data quality, design effect and sample size. Out of the 533 surveys showing departure from a normal distribution, 294 (55.2 %) showed high digit preference, 164 (30.8 %) had a large design effect, and 204 (38.3 %) a large sample size. Spline and LOESS smoothing techniques were explored and both techniques work well. After Spline smoothing, 56.7 % of the MUAC distributions showing departure from normality were "normalised" and 59.7 % after LOESS. Box-Cox power transformation had similar results on distributions showing departure from normality with 57 % of distributions approximating "normal" after transformation. Applying Box-Cox transformation after Spline or Loess smoothing techniques increased that proportion to 82.4 and 82.7 % respectively. CONCLUSION: This suggests that statistical approaches relying on the normal distribution assumption can be successfully applied to MUAC. In light of this promising finding, further research is ongoing to evaluate the performance of a normal distribution based approach to estimating the prevalence of wasting using MUAC

Anthropometric indices and measures to assess change in the nutritional status of a population: a systematic literature review

Background: Undernutrition is a major public health issue highlighted by the 2015 Sustainable Development Goals, with target 2.2 aiming to 'end hunger' by 2030. On-going surveillance is essential detecting nutritional stress in a population and is key to planning consequent interventions. Whilst methodologies of nutritional surveillance systems vary across different settings, organisations and even within the same country, the direct evidence-base underpinning these practices is limited. This paper aims therefore to: 1) compare the performance of different anthropometric indices/measurements for detecting change in the nutritional situation at population level; 2) discuss their properties and appropriateness for use in a surveillance system. Methods: This systematic literature review considered peer-reviewed and grey literature. Evidence was compiled from standard electronic databases, websites and snowballing. The search was performed in November 2015 by a single reviewer using the following terms to capture two concepts: 1) Undernutrition and 2) Nutrition surveillance. The search was limited to children under five and the period considered started in 1980. Languages included English and French. Articles had to assess whether the changes or trend observed at population level were statistically significant. All study designs were included. Results: A total of 4563 articles were retrieved from the electronic database search. Most articles (3137, 89%) were not directly relevant based on title and abstract; 39 articles were reviewed in full. A total of 17 articles met the inclusion criteria and an additional 4 papers were added after snowballing. A number of measures and indices such as weight, weight-for-height/length, triceps skinfold and middle-upper arm circumference performed well in the detection of short term changes in the nutritional situation of a population. Height/Length-for-age responded the most to long term change. Applying a standard set of criteria (simplicity, acceptability, cost, independence of age, reliability and accuracy) to determine which is the most appropriate measure or index identified middle-upper arm circumference as the one with the greatest net benefits. Conclusions: Limited available evidence suggests that mid-upper arm circumference is the best measure to detect short term changes in the nutritional state of a population: this should receive higher priority in surveillance systems

A novel, efficient method for estimating the prevalence of acute malnutrition in resource-constrained and crisis-affected settings: A simulation study.

INTRODUCTION: The assessment of the prevalence of acute malnutrition in children under five is widely used for the detection of emergencies, planning interventions, advocacy, and monitoring and evaluation. This study examined PROBIT Methods which convert parameters (mean and standard deviation (SD)) of a normally distributed variable to a cumulative probability below any cut-off to estimate acute malnutrition in children under five using Middle-Upper Arm Circumference (MUAC). METHODS: We assessed the performance of: PROBIT Method I, with mean MUAC from the survey sample and MUAC SD from a database of previous surveys; and PROBIT Method II, with mean and SD of MUAC observed in the survey sample. Specifically, we generated sub-samples from 852 survey datasets, simulating 100 surveys for eight sample sizes. Overall the methods were tested on 681 600 simulated surveys. RESULTS: PROBIT methods relying on sample sizes as small as 50 had better performance than the classic method for estimating and classifying the prevalence of acute malnutrition. They had better precision in the estimation of acute malnutrition for all sample sizes and better coverage for smaller sample sizes, while having relatively little bias. They classified situations accurately for a threshold of 5% acute malnutrition. Both PROBIT methods had similar outcomes. CONCLUSIONS: PROBIT Methods have a clear advantage in the assessment of acute malnutrition prevalence based on MUAC, compared to the classic method. Their use would require much lower sample sizes, thus enable great time and resource savings and permit timely and/or locally relevant prevalence estimates of acute malnutrition for a swift and well-targeted response

Feeding Interventions for Infants with Growth Failure in the First Six Months of Life: A Systematic Review.

(1) Introduction: Current evidence on managing infants under six months with growth failure or other nutrition-related risk is sparse and low quality. This review aims to inform research priorities to fill this evidence gap, focusing on breastfeeding practices. (2) Methods: We searched PubMed, CINAHL Plus, and Cochrane Library for studies on feeding interventions that aim to restore or improve the volume or quality of breastmilk and breastfeeding when breastfeeding practices are sub-optimal or prematurely stopped. We included studies from both low- and middle-income countries and high-income countries. (3) Results: Forty-seven studies met the inclusion criteria. Most were from high-income countries (n = 35, 74.5%) and included infants who were at risk of growth failure at birth (preterm infants/small for gestational age) and newborns with early growth faltering. Interventions included formula fortification or supplementation (n = 31, 66%), enteral feeds (n = 8, 17%), cup feeding (n = 2, 4.2%), and other (n = 6, 12.8%). Outcomes included anthropometric change (n = 40, 85.1%), reported feeding practices (n = 16, 34%), morbidity (n = 11, 23.4%), and mortality (n = 5, 10.6%). Of 31 studies that assessed formula fortification or supplementation, 30 reported anthropometric changes (n = 17 no effect, n = 9 positive, n = 4 mixed), seven morbidity (n = 3 no effect, n = 2 positive, n = 2 negative), five feeding (n = 2 positive, n = 2 no effect, n = 1 negative), and four mortality (n = 3 no effect, n = 1 negative). Of eight studies that assessed enteral feed interventions, seven reported anthropometric changes (n = 4 positive, n = 3 no effect), five feeding practices (n = 2 positive, n = 2 no effect, n = 1 negative), four morbidity (n = 4 no effect), and one reported mortality (n = 1 no effect). Overall, interventions with positive effects on feeding practices were cup feeding compared to bottle-feeding among preterm; nasogastric tube feed compared to bottle-feeding among low birth weight preterm; and early progressive feeding compared to delayed feeding among extremely low birth weight preterm. Bovine/cow milk feeding and high volume feeding interventions had an unfavourable effect, while electric breast pump and Galactagogue had a mixed effect. Regarding anthropometric outcomes, overall, macronutrient fortified formula, cream supplementation, and fortified human milk formula had a positive effect (weight gain) on preterm infants. Interventions comparing human breastmilk/donor milk with formula had mixed effects. Overall, only human milk compared to formula intervention had a positive effect on morbidity among preterm infants, while none of the interventions had any positive effect on mortality. Bovine/cow milk supplementation had unfavourable effects on both morbidity and mortality. (4) Conclusion: Future research should prioritise low- and middle-income countries, include infants presenting with growth failure in the post-neonatal period and record effects on morbidity and mortality outcomes

Exposure to the 1959–1961 Chinese famine and risk of non-communicable diseases in later life: A life course perspective

<jats:p>Child undernutrition and later-life non-communicable diseases (NCDs) are major global health issues. Literature suggests that undernutrition/famine exposure in childhood has immediate and long-term adverse health consequences. However, many studies have theoretical and methodological limitations. To add to the literature and overcome some of these limitations, we adopted a life course perspective and used more robust methods. We investigated the association between exposure to the 1959–1961 Chinese famine and later-life NCDs and if this association depends on: life stage at exposure, famine severity, and sex. We conducted a secondary data analysis of a large-scale, nationally representative, longitudinal study—the China Health and Retirement Longitudinal Study (2011–2018, 11,094 participants). We measured famine exposure/severity using self-reported experience, life stage using age at exposure, and health using the number of NCDs. We performed Poisson growth curve models. We obtained three findings. First, compared with unexposed participants, those exposed before age 18 had a higher risk of later-life NCDs, particularly if exposed in-utero (IRR = 1.90, 95% CI [1.70, 2.12], <jats:italic>p</jats:italic> < .001) and in the “first 1,000 days” of life (IRR = 1.86, 95% CI [1.73, 2.00], <jats:italic>p</jats:italic> < .001; for 0–6 months group, IRR = 1.95, 95% CI [1.67, 2.29], <jats:italic>p</jats:italic> < .001). Second, the famine effects among participants moderately and severely exposed were similar (IRR = 1.18, 95% CI [1.09, 1.28], <jats:italic>p</jats:italic> < .001 and IRR = 1.24, 95% CI [1.17, 1.32], <jats:italic>p</jats:italic> < .001). Third, the famine effects did not differ between females and males (IRR = 0.98, 95% CI [0.90, 1.07], <jats:italic>p</jats:italic> = .703). In an individual’s life course, in-utero and the “first 1,000 days” are a particularly sensitive time period with marked long-term implications for NCDs if undernutrition/famine is experienced in this period. However, this window remains open until young adulthood. This highlights the need to invest more in preventing and treating child/adolescent undernutrition to tackle later-life NCDs.</jats:p&gt

Management of acute malnutrition in infants aged under 6 months (MAMI): current issues and future directions in policy and research.

BACKGROUND: Globally, some 4.7 million infants aged under 6 months are moderately wasted and 3.8 million are severely wasted. Traditionally, they have been over-looked by clinicians, nutritionists, and policy makers. OBJECTIVE: To present evidence and arguments for why treating acute malnutrition in infants under 6 months of age is important and outline some of the key debates and research questions needed to advance their care. METHODS: Narrative review. RESULTS AND CONCLUSIONS: Treating malnourished infants under 6 months of age is important to avoid malnutrition-associated mortality in the short-term and adverse health and development outcomes in the long-term. Physiological and pathological differences demand a different approach from that in older children; key among these is a focus on exclusive breastfeeding wherever possible. New World Health Organization guidelines for the management of severe acute malnutrition (SAM) include this age group for the first time and are also applicable to management of moderate acute malnutrition (MAM). Community-based breastfeeding support is the core, but not the sole, treatment. The mother-infant dyad is at the heart of approaches, but wider family and community relationships are also important. An urgent priority is to develop better case definitions; criteria based on mid-upper-arm circumference (MUAC) are promising but need further research. To effectively move forward, clinical trials of assessment and treatment are needed to bolster the currently sparse evidence base. In the meantime, nutrition surveys and screening at health facilities should routinely include infants under 6 months of age in order to better define the burden and outcomes of acute malnutrition in this age group