Inconsistent diagnosis of acute malnutrition by weight-for-height and mid-upper arm circumference: contributors in 16 cross-sectional surveys from South Sudan, the Philippines, Chad, and Bangladesh

Three-arm clinical trial of improved flour targeting intestinal microbiota (MALINEA)

The main objective of this project was to compare in the field conditions two strategies of re-nutrition of children with moderate acute malnutrition (MAM) aged from 6 to 24 months, targeting the microbiota in comparison with a standard regimen. A three-arm, open-label, pragmatic randomised trial was conducted in four countries (Niger, CAR, Senegal and Madagascar). Children received for 12 weeks either fortified blended flour (FBF control) = arm 1, or FBF + azithromycin (oral suspension of 20 mg/kg/day daily given with a syringe) for the first 3 days at inclusion = arm 2 or mix FBF with inulin/fructo-oligosaccharides (6 g/day if age ≥12 months and 4 g if age <12 months) = arm 3. For each arm, children aged from 6 to 11 months received 100 g x 2 per day of flours and those aged from 12 to 24 months received 100 g × 3 per day of FBF. The primary endpoint was nutritional recovery, defined by reaching a weight-for-height z-score (WHZ) ≥ -1.5 within 12 weeks. Overall, 881 children were randomised (297, 290 and 294 in arm 1, arm 2 and arm 3, respectively). Three hundred and forty-four children were males (39%) and median/mean age were 14.6/14.4 months (SD = 4.9, IQR = 10.5-18.4). At inclusion, the three arms were comparable for all criteria, but differences were observed between countries. Overall, 44% (390/881) of the children recovered at week 12 from MAM, with no significant difference between the three arms (41.4%, 45.5% and 45.9%, in arm 1, arm 2 and arm 3, respectively, p = 0.47). This study did not support the true advantages of adding a prebiotic or antibiotic to flour. When using a threshold of WHZ ≥ -2 as an exploratory endpoint, significant differences were observed between the three arms, with higher success rates in arms with antibiotics or prebiotics compared to the control arm (66.9%, 66.0% and 55.2%, respectively, p = 0.005).

Arm circumference for age, arm circumference and weight-for-height z-score for the evaluation of severe acute malnutrition: a retrospective cohort study in eastern Democratic Republic of Congo

BACKGROUND

Little is known about the use of mid-upper arm circumference for age (MUACZ) for diagnosing of severe acute malnutrition (SAM) and its correlation with WHZ (weight-for-height Z-score) in an area endemic for severe acute malnutrition (SAM) and with a high prevalence of kwashiorkor. Our study aims to analyze the concordance between the diagnostic criteria of SAM in a region presenting these characteristics.

METHODS

We analyzed a database of children admitted from 1987 to 2008 for the management of SAM in Eastern Democratic Republic of Congo. Anthropometric indicators (z-score) were calculated and classified into 3 categories according to WHO standards. Cohen's kappa coefficient (κ) was calculated to assess the concordance between these indicators.

RESULTS

Out of the 9969 selected children aged 6 to 59 months, 30.2% had nutritional edema, 70.1% had a height-for-age (HAZ) z-score <-2, 11.5% WHZ<-3 z-score, 14.9% had a MUAC < 115 mm and 21.8% had a MUACZ <-3 z-score. With the classic combination WHZ and MUAC, 36% of children with SAM had both criteria at the same time and MUAC alone being the indicator that recruited more children with SAM (77%) compared with 65% with WHZ only. By replacing MUAC with MUACZ, 34% of SAM children fulfilled both criteria, WHZ and MUACZ. MUACZ alone recruited more children with SAM (88%) compared with 46% with WHZ alone. Considering these three indicators together, MUACZ remained the indicator that recruited more children with SAM (85%). WHZ and MUAC showed a moderate agreement [ κ (95% CI) = 0.408(0.392-0.424)], WHZ and MUACZ a weak agreement [ κ (95% CI) = 0.363(0.347-0.379)] and MUAC and MUACZ a good agreement [ κ (95% CI) = 0.604 (0.590-0.618)].

CONCLUSION

Adjusting MUAC according to age improves its effectiveness in identifying severe acute malnutrition. With low concordance, MUAC and WHZ remain complementary in our context. MUACZ proves to be crucial, especially in the presence of kwashiorkor and chronic malnutrition, becoming a valuable tool for assessing severe acute malnutrition in our context.

Mid-upper arm circumference only protocol in Pakistan: missed opportunities for children suffering from severe acute malnutrition? A mixed-methods observational study

OBJECTIVE

We investigated the missed treatment opportunities affecting programmes using mid-upper arm circumference (MUAC) as the sole anthropometric criterion for identification and monitoring of children suffering from severe acute malnutrition (SAM).

DESIGN

Alongside MUAC, we assessed weight-for-height Z-score (WHZ) in children screened and treated according to the national MUAC only protocol in Pakistan. Besides, we collected parents' perceptions regarding the treatment received by their children through qualitative interviews.

SETTING

Data were collected from October to December 2021 in Tando Allah Yar District, Sindh.

SUBJECTS

All children screened in the health facilities (n 8818) and all those discharged as recovered (n 686), throughout the district, contributed to the study. All children screened in the community in the catchment areas of five selected health facilities also contributed (n 8459). Parents of forty-one children randomly selected from these same facilities participated in the interviews.

RESULTS

Overall, 80·3 % of the SAM cases identified during community screening and 64·1 % of those identified in the health facilities presented a 'WHZ-only' diagnosis. These figures reached 93·9 % and 84·5 %, respectively, in children aged over 24 months. Among children treated for SAM and discharged as recovered, 25·3 % were still severely wasted according to WHZ. While parents positively appraised the treatment received by their children, they also recommended to extend eligibility to other malnourished children in their neighbourhood.

CONCLUSION

In this context, using MUAC as the sole anthropometric criterion for treatment decisions (referral, admission and discharge) resulted in a large number of missed opportunities for children in need of timely and adequate care.

Prognostic value of different anthropometric indices over different measurement intervals to predict mortality in 6-59-month-old children

OBJECTIVE

To compare the prognostic value of mid-upper arm circumference (MUAC), weight-for-height Z-score (WHZ) and weight-for-age Z-score (WAZ) for predicting death over periods of 1, 3 and 6 months follow-up in children.

DESIGN

Pooled analysis of twelve prospective studies examining survival after anthropometric assessment. Sensitivity and false-positive ratios to predict death within 1, 3 and 6 months were compared for three individual anthropometric indices and their combinations.

SETTING

Community-based, prospective studies from twelve countries in Africa and Asia.

PARTICIPANTS

Children aged 6-59 months living in the study areas.

RESULTS

For all anthropometric indices, the receiver operating characteristic curves were higher for shorter than for longer durations of follow-up. Sensitivity was higher for death with 1-month follow-up compared with 6 months by 49 % (95 % CI (30, 69)) for MUAC < 115 mm (P < 0·001), 48 % (95 % CI (9·4, 87)) for WHZ < -3 (P < 0·01) and 28 % (95 % CI (7·6, 42)) for WAZ < -3 (P < 0·005). This was accompanied by an increase in false positives of only 3 % or less. For all durations of follow-up, WAZ < -3 identified more children who died and were not identified by WHZ < -3 or by MUAC < 115 mm, 120 mm or 125 mm, but the use of WAZ < -3 led to an increased false-positive ratio up to 16·4 % (95 % CI (12·0, 20·9)) compared with 3·5 % (95 % CI (0·4, 6·5)) for MUAC < 115 mm alone.

CONCLUSIONS

Frequent anthropometric measurements significantly improve the identification of malnourished children with a high risk of death without markedly increasing false positives. Combining two indices increases sensitivity but also increases false positives among children meeting case definitions.

Factors associated with acute malnutrition among children aged 6-59 months in Haiti, Burkina Faso and Madagascar: A pooled analysis

BACKGROUND

Acute malnutrition is one of the main causes of morbidity and mortality among children under 5 years worldwide, and Action Contre la Faim (ACF) aims to address its causes and consequences. To better tailor humanitarian programs, ACF conducts standardized contextual studies called Link NCAs (Nutrition Causal Analysis), to identify factors associated with severe acute malnutrition (SAM) and moderate acute malnutrition (MAM). Data from three Link NCAs performed in 2018 and 2019 in Haiti, Burkina Faso and Madagascar were used to explore the prevalence of malnutrition by different indicators and associated risk factors among children aged 6-59 months.

METHODS

Cross-sectional data, collected via household surveys applying two-stage cluster sampling, were pooled to build a sample of 1,356 children. Recommended anthropometric thresholds were used to define SAM (Weight-for-Height Z-score (WHZ) <-3 or Mid-upper Arm Circumference (MUAC) <115 mm and/or presence oedema), MAM (-3≤WHZ<-2 or 115≤MUAC<125 mm) and global acute malnutrition GAM (SAM or MAM) among children. Multivariate analyses for each anthropometric indicator were performed using logistic mixed models and adjusting for potential confounders.

RESULTS

The prevalence of acute malnutrition was the highest in Madagascar. The risk of having GAM and MAM varied across countries, while the risk of having SAM varied across clusters. Being male, suffering from diarrhea, and having unwashed face and hands, were significantly associated with GAM by WHZ with adjusted odds ratio of 1.9 [95%Confidence interval (CI):1.1-3.2], 1.7 (95%CI: 1.0-3.1) and 1.9 (95%CI: 1.0-3.6) respectively. These factors were also associated with MAM by WHZ. None of the studied factors was significantly associated with SAM, which could be due to a small sample size.

CONCLUSION

These results obtained from a large sample contribute to the evidence of the factors associated with undernutrition in children aged 6-59 months. Further research with larger sample sizes is needed to confirm these results.

Public Health Implications of Wasting and Stunting Relationship in Children under Five Years Highly Vulnerable to Undernutrition in Guatemala: The REDAC Study

(1) Background: Guatemala is the Latin American country with the highest prevalence of childhood stunting. Short height can bias the diagnosis of wasting when using the weight-for-height indicator. The aim of this study was to evaluate the diagnostic concordance of the anthropometric indicators of wasting and the relationship between wasting and stunting in children from highly vulnerable communities in Guatemala. (2) Methods: The sample consisted of 13,031 anthropometric records of children under five years of age (49.5% girls, average age of 27.9 months), including weight, height, and mid-upper arm circumference (MUAC), collected in March–August 2019. The proportions of stunting, underweight, and wasting, assessed by three different indicators, as well as their concurrence through the Composite Index of Anthropometric Failure were calculated. (3) Results: Stunting affected 73% of the sample, and 74.2% showed anthropometric failure. Wasting varied by indicator (weight-for-height: 2.8%; MUAC: 4.4%; MUAC-for-age: 10.6%). Concordance between MUAC and weight-for-height was very low (Kappa: 0.310; sensitivity: 40.9%). MUAC identified more wasted children in the stunted group (53.6% vs. 26.5%), while the opposite occurred in the non-stunted group (34.8% vs. 46.7%). (4) Conclusion: The presence of stunting affected the diagnosis of wasting, and both indicators should be included as diagnostic criteria for screening campaigns and in the treatment of moderate to acute wasting in vulnerable populations affected by multiple forms of undernutrition.

Concordance Between Indices of Malnutrition: Mid-Upper Arm Circumference V/S Weight for the Height Z Score in Different Age Groups in Karachi, Pakistan

Objective

To compare the WHO cut-off of the mid-upper arm circumference (MUAC) with the weight for height z-score (WHZ) in different age groups of children (6 months to 59 months of age) with acute malnutrition in Pakistan.

Methodology

A cross-sectional study was carried out in the pediatric unit of Ziauddin Medical University and Hospital on malnourished children from six to 59 months of age to compare two different indices of malnutrition, MUAC and WHZ. A total of 450 children with WHZ of <-2SD and <-3SD were included in the study after excluding children with failure to thrive due to chronic illness, congenital defects, and immune deficiencies/malabsorption.

Results

The study revealed a significant mean difference in weight, height, and MUAC among the participants (0.030, 0.053, and 0.02). The sensitivity of MUAC at <11.5 cm was highest in the 12-24-month age group with a decline at 24-48 months while specificity was highest at six to 12 months of age, which shows a mixed response.

Conclusion

The result revealed variation in the cut-off value of MUAC in different age groups; the best specificity of MUAC was found at six to 12 months of age and the best sensitivity at 12-24 months of age.

Changing mortality amongst hospitalised children with Severe Acute Malnutrition in KwaZulu-Natal, South Africa, 2009 - 2018

Background

The under-five mortality rates of children in South Africa (SA) remain high despite successful HIV prevention and treatment programs. The in-hospital mortality of children with severe acute malnutrition remains a key obstacle. This study identifies and describes changes in the mortality of under-five children with severe acute malnutrition (SAM) following the implementation of HIV and malnutrition prevention and treatment programmes.

Methods

This was a retrospective review of in-hospital mortality records and databases. The study was based at a large referral hospital in KwaZulu-Natal (KZN), where HIV and malnutrition rates are high, and SAM children are managed with standard WHO guidelines. Records of children under five years old who died from 2009 to 2018 were analysed.

Results

Of the 698 under-five children who died in this period, 285 (40, 8% of all under-5 deaths) were classified as having SAM. The number of HIV-infected SAM deaths dropped significantly, especially those below six months of age, mirroring the expansion of HIV treatment and prevention programmes. Despite this and a significant drop in the proportion of SAM admissions identified, there was no change in SAM case fatality rates over the ten years. Septicaemia remained the most common cause of death in children with SAM.

Conclusions

Despite significant decreases in HIV-related malnutrition deaths over ten years, the lack of change in SAM case fatality rates is a concern at this referral hospital. Standardised WHO inpatient management protocols, may require review, especially where underlying medical conditions may contribute to SAM deaths in HIV-negative children.

Clinical and Biochemical Markers of Risk in Uncomplicated Severe Acute Malnutrition

BACKGROUND AND OBJECTIVES

Use of mid-upper arm circumference (MUAC) as a single screening tool for severe acute malnutrition (SAM) assumes that children with a low weight-for-height z score (WHZ) and normal MUAC have lower risks of morbidity and mortality. However, the pathophysiology and functional severity associated with different anthropometric phenotypes of SAM have never been well characterized. We compared clinical characteristics, biochemical features, and health and nutrition histories of nonedematous children with SAM who had (1) low WHZ only, (2) both low WHZ and low MUAC, or (3) low MUAC only.

METHODS

In Bangladesh, Burkina Faso, and Liberia, we conducted a multicentric cohort study in uncomplicated, nonedematous children with SAM and low MUAC only (n = 161), low WHZ only (n = 138), or a combination of low MUAC and low WHZ (n = 152). Alongside routine anthropometric measurements, we collected a wide range of critical indicators of clinical and nutritional status and viability; these included serum leptin, an adipocytokine negatively associated with mortality risk in SAM.

RESULTS

Median leptin levels at diagnosis were lower in children with low WHZ only (215.8 pg/mL; P < .001) and in those with combined WHZ and MUAC deficits (180.1 pg/mL; P < .001) than in children with low MUAC only (331.50 pg/mL). The same pattern emerged on a wide range of clinical indicators, including signs of severe wasting, dehydration, serum ferritin levels, and caretaker-reported health deterioration, and was replicated across study sites.

CONCLUSIONS

Illustrative of the likely heterogeneous functional severity of the different anthropometric phenotypes of SAM, our results confirm the need to retain low WHZ as an independent diagnostic criterion.

Comparison of Mid-Upper-Arm Circumference and Weight-For-Height Z-Score in Identifying Severe Acute Malnutrition among Children Aged 6-59 Months in South Gondar Zone, Ethiopia

Children with severe acute malnutrition (SAM) are identified for admission to outpatient therapeutic programs using mid-upper-arm circumference (MUAC) or weight for height (WHZ). However, MUAC and WHZ do not identify the same children, and such observed differences might have programmatic implications of missed nutrition therapy if only MUAC is used to identify children with SAM. The objective of the study was to assess any difference in prevalence and degree of agreement between MUAC and WHZ in identifying SAM affected children. A cross-sectional study was conducted in South Gondar Zone, Ethiopia, among 17 districts, with 3 districts and 10 health centers with their clustered health posts selected randomly. A total of 2,040 children were recruited, and data were collected using a parent questionnaire then entered into EpiData and analyzed using SPSS v 20. A total of 1,980 respondents (97.1%) were interviewed, all of whom were female and rural residents. Children's mean age in months was 23.2 (SD ± 9.7), and 54% were male children. The prevalence of SAM based on MUAC <11.5 cm was 11.2% (95% CI: 9.9–12.7) and 11.0% (95% CI: 9.7–12.5) based on WHZ <−3. The agreement between MUAC and WHZ was good (k = 0.729). The proportion of children with SAM identified using both MUAC and WHZ was 61.2%. The prevalence of SAM identified using both MUAC and WHZ was comparable. A substantial degree of agreement between MUAC and WHZ was observed to diagnose SAM. Therefore, MUAC can be used as an appropriate tool in identifying children with SAM for admission into the outpatient therapeutic program (OTP) in the study area.

Anthropometry at discharge and risk of relapse in children treated for severe acute malnutrition: a prospective cohort study in rural Nepal

Background

There is a dearth of evidence on what should be the optimal criteria for discharging children from severe acute malnutrition (SAM) treatment. Programs discharging children while they are still presenting varying levels of weight-for-height (WHZ) or mid-upper-arm circumference (MUAC) deficits, such as those implemented under the current national protocol in Nepal, are opportunities to fill this evidence gap.

Methods

We followed a cohort of children discharged as cured from SAM treatment in Parasi district, Nepal. Relapse as SAM, defined as the occurrence of WHZ<-3 or MUAC < 115 mm or nutritional edema, was investigated through repeated home visits, during six months after discharge. We assessed the contribution of remaining anthropometric deficits at discharge to relapse risk through Cox regressions.

Results

Relapse as SAM during follow-up was observed in 33 % of the cohort (35/108). Being discharged before reaching the internationally recommended criteria was overall associated with a large increase in the risk of relapse (HR = 3.3; p = 0.006). Among all anthropometric indicators at discharge, WHZ<-2 led to a three-fold increase in relapse risk (HR = 3.2; p = 0.003), while MUAC < 125 mm significantly raised it only in the older children. WHZ<-2 at discharge came up as the only significant predictor of relapse in multivariate analysis (HR = 2.8, p = 0.01), even among children with a MUAC ≥ 125 mm. Of note, more than 80 % of the events of relapse as SAM would have been missed if WHZ had not been monitored and used in the definition of relapse.

Conclusions

Our results suggest that the priority for SAM management programs should be to ensure that children reach a high level of WHZ at discharge, at least above or equal to the WHO recommended cut-off. The validity of using a single MUAC cut-off such as 125 mm as a suitable discharge criterion for all age groups is questioned. Further follow-up studies providing a complete assessment of nutritional status at discharge and not based on a restricted MUAC-only definition of relapse as SAM would be urgently needed to set evidence-based discharge criteria. These studies are also required to assess programs currently discounting or omitting WHZ for identification and management of SAM.

Diagnostic Concordance between Random Upper Arm Circumference and Mid Upper Arm Circumference Measurements among Children Aged 6-59 Months in South Ethiopia: A Community-Based Cross-Sectional Study

Random upper arm circumference (RUAC) is frequently used for malnutrition screening among children aged 6-59 months. However, inadequate evidence exists regarding its agreement with mid upper arm circumference (MUAC). This study examined diagnostic concordance between RUAC and standard MUAC measurements and tested RUAC's ability for screening malnutrition among children aged 6-59 months. A cross-sectional study was conducted from April 30 to May 30/2015 in Ethiopia. Data were taken from a sample of 819 children aged 6-59 months with a simple random sampling technique. The data were analyzed using SPSS version 22 software. The kappa agreement level, sensitivity, and specificity were calculated. The receiver operating curve was prepared to determine the optimal cutoff RUAC for the sensitivity and specificity. With National Center for Health Statistics (NCHS) cutoff (12 cm), the performance of RUAC measurements in terms of sensitivity was low (44%). The kappa agreement level between the two measurements was 0.551 (p value < 0.001). With the new WHO cutoff (12.5 cm), however, RUAC was improved in validity (sensitivity 81%), specificity 96.9%, and kappa agreement level (K = 0.807; p < 0.001).

Association between admission criteria and body composition among young children with moderate acute malnutrition, a cross-sectional study from Burkina Faso

Children with moderate acute malnutrition (MAM) are treated based on low weight-for-length z-score (WLZ), low mid-upper arm circumference (MUAC) or both. This study aimed to assess associations of admission criteria and body composition (BC), to improve treatment of MAM. We undertook a cross-sectional study among 6–23 months old Burkinabe children with MAM. Fat-free (FFM) and fat mass (FM) were determined by deuterium dilution and expressed as FFM (FFMI) and FM index (FMI). Of 1,489 children, 439 (29.5%) were recruited by low MUAC only (MUAC-O), 734 (49.3%) by low WLZ and low MUAC (WLZ-MUAC) and 316 (21.2%) by low WLZ only (WLZ-O). Thus, 1,173 (78.8%) were recruited by low MUAC, with or without low WLZ (ALL-MUAC). After adjustments, WLZ-O had 89 g (95% confidence interval (CI) 5; 172) lower FFM compared to MUAC-O. Similarly, WLZ-O had 0.89 kg/m² (95% CI 0.77; 1.01) lower FFMI compared to MUAC-O, whereas there was no difference for FMI. However, boys included by WLZ-O compared to MUAC-O had 0.21 kg/m² (95% CI 0.05; 0.38) higher FMI. In contrast, girls included by WLZ-O had 0.17 (95% CI 0.01; 0.33) kg/m² lower FMI compared to MUAC-O (interaction, p = 0.002). We found that different criteria for admission into MAM treatment programmes select children with differences in BC, especially FFMI.

Trial registration: ISRCTN42569496.

Potential consequences of expanded MUAC-only programs on targeting of acutely malnourished children and ready-to-use-therapeutic-food allocation: lessons from cross-sectional surveys

Background

Some of the recently piloted innovative approaches for the management of acute malnutrition in children use the “expanded MUAC-only” approach, with Mid Upper Arm Circumference (MUAC) < 125 mm as the sole anthropometric criterion for screening and admission, classification of cases as severe using the 115 mm cut-off, and use Ready-to-Use-Therapeutic-Food (RUTF) for the management of both moderate (MAM) and severe (SAM) cases of acute malnutrition. Our study aimed at exploring the potential consequences of this “expanded MUAC-only” program scenario on the eligibility for treatment and RUTF allocation, as compared with the existing WHO normative guidance.

Methods

We analyzed data from 550 population representative cross-sectional cluster surveys conducted since 2007. We retrieved all children classified as SAM and MAM according to currently used case definitions, and calculated the proportions of SAM children who would be excluded from treatment, misclassified as MAM, or whose specific risks (because of having both MUAC and weight-for height deficits) would be ignored. We also analyzed the expected changes in the number and demographics (sex, age) of children meant to receive RUTF according to the new approach.

Results

We found that approximately one quarter of SAM children would not be detected and eligible for treatment under the “expanded MUAC-only” scenario, and another 20% would be classified as MAM. A further 17% of the total SAM children would be admitted and followed only according to their MUAC or oedema status, while they also present with a severe weight-for height deficit on admission. Considering MAM targeting, about half of the MAM children would be left undetected. This scenario also shows a 2.5 time increase in the number of children targeted with RUTF, with approximately 70% of MAM and 30% of SAM cases among this new RUTF target.

Conclusions

This empirical evidence suggests that adoption of “expanded MUAC-only” programs would likely lead to a priori exclusion from treatment or misclassifying as MAM a large proportion of SAM cases, while redirecting programmatic costs in favor of those less in need. It underscores the need to explore other options for improving the impact of programs addressing the needs of acutely malnourished children.

Combined protocol for severe and moderate acute malnutrition in emergencies: Stakeholders perspectives in four countries

Each year, acute malnutrition affects an estimated 52 million children under 5 years of age. Current global treatment protocols divide treatment of severe acute malnutrition (SAM) and moderate acute malnutrition (MAM) despite malnutrition being a spectrum disease. A proposed Combined Protocol provides for (a) treatment of MAM and SAM at the same location; (b) diagnosis using middle‐upper‐arm circumference (MUAC) and oedema only; (c) treatment using a single product, ready‐to‐use‐therapeutic food (RUTF), and (d) a simplified dosage schedule for RUTF. This study examines stakeholders' knowledge of and opinions on the Combined Protocol in Niger, Nigeria, Somalia, and South Sudan. Data collection included a document review followed by in‐depth interviews with 50 respondents from government, implementing partners, and multilateral agencies, plus 11 global and regional stakeholders. Data were analysed iteratively using thematic content analysis. We find that acute malnutrition protocols in these countries have not been substantially modified to include components of the Combined Protocol, although aspects were accepted for use in emergencies. Respondents generally agreed that MAM and SAM treatment should be provided in the same location, however they said MUAC and oedema‐only diagnosis, although more field‐ready than other diagnostic measures, did not necessarily catch all malnourished children and may not be appropriate for “tall and slim” morphologies. Similarly, using only RUTF presented inherent logistical advantages, but respondents worried about pipeline issues. Respondents did not express strong opinions about simplified dosage schedules. Stakeholders interviewed indicated more evidence is needed on the operational implications and effectiveness of the Combined Protocol in different contexts.

Severe acute malnutrition and mortality in children in the community: Comparison of indicators in a multi-country pooled analysis

OBJECTIVES

This study aims to describe the mortality risk of children in the community who had severe acute malnutrition (SAM) defined by either a mid-upper arm circumference (MUAC) <115mm, a low weight-for-height Z-score (WHZ) <-3 or both criteria.

METHODS

We pooled individual-level data from children aged 6-59 months enrolled in 3 community-based studies in the Democratic Republic of the Congo (DRC), Senegal and Nepal. We estimate the mortality hazard using Cox proportional hazard models in groups defined by either anthropometric indicator.

RESULTS

In total, we had 49,001 time points provided by 15,060 children available for analysis, summing to a total of 143,512 person-months. We found an increasing death rate with a deteriorating nutritional status for all anthropometrical indicators. Children identified as SAM only by a low MUAC (<115mm) and those identified only by a low WHZ (Z-score <-3) had a similar mortality hazard which was about 4 times higher than those without an anthropometric deficit. Having both a low MUAC and a low WHZ was associated with an 8 times higher hazard of dying compared to children within the normal range. The 2 indicators identified a different set of children; the proportion of children identified by both indicators independently ranged from 7% in the DRC cohort, to 35% and 37% in the Senegal and the Nepal cohort respectively.

CONCLUSION

In the light of an increasing popularity of using MUAC as the sole indicator to identify SAM children, we show that children who have a low WHZ, but a MUAC above the cut-off would be omitted from diagnosis and treatment despite having a similar risk of death.

Examining Mid-Upper Arm Circumference Malnutrition z-Score Thresholds

BACKGROUND

Anthropometric z-scores used commonly for diagnosis and determining degree of malnutrition, specifically body mass index (BMIz), weight-for-length (WLz), and mid-upper arm circumference (MUACz), are not wholly concordant, yet the proposed thresholds for classification are identical. This study was designed to critically examine MUACz thresholds and their ability to correctly classify nutrition status.

METHODS

This was a 2-year, prospective single-center study of children ≤18 years seen by registered dietitians within a large pediatric institution. The sensitivity, specificity, and predictive performance of the malnutrition classification thresholds were estimated against clinician-based classification.

RESULTS

Sixty-one dietitians enrolled 10,401 patients with distributions of z-scores for weight (-0.5 ± 1.9), length (-0.8 ± 1.6), BMI or WL (-0.1 ± 1.8), and MUAC (-0.4 ± 1.5), suggesting participants were smaller and shorter than the reference U.S.

POPULATION

Distributions of MUACz were broad and overlapped between nutrition classification groups, an observation that extended to BMIz and WLz as well. Consequently, existing thresholds do not accurately classify 100% of children. Misclassification rates increase, with increasing severity ranging from 8% in children with no malnutrition to 71% in children with severe malnutrition. Algorithm- and manually-based refinement of thresholds result in mixed improvements and can be explored by the reader with the associated supplement.

CONCLUSION

The sensitivity of proposed MUACz thresholds systematically decreases with increasing severity of malnutrition and will require optimization if we aim to limit the number of children at risk of misclassification. Indicators for overnutrition remain to be addressed but are explored herein.

Performance of mid-upper arm circumference to diagnose acute malnutrition in a cross-sectional community-based sample of children aged 6-24 months in Niger

BACKGROUND/OBJECTIVES

Accurate, early identification of acutely malnourished children has the potential to reduce related child morbidity and mortality. The current World Health Organisation (WHO) guidelines classify non-oedematous acute malnutrition among children under five using Mid-Upper Arm Circumference (MUAC) or Weight-for-Height Z-score (WHZ). However, there is ongoing debate regarding the use of current MUAC cut-offs. This study investigates the diagnostic performance of MUAC to identify children aged 6–24 months with global (GAM) or severe acute malnutrition (SAM).

SUBJECTS/METHODS

Cross-sectional, secondary data from a community sample of children aged 6-24 months in Niger were used for this study. Children with complete weight, height and MUAC data and without clinical oedema were included. Using WHO guidelines for GAM (WHZ < −2, MUAC < 12.5 cm) and SAM (WHZ < −3, MUAC < 11.5 cm), the sensitivity (Se), specificity (Sp), predictive values, Youden Index and Receiver Operating Characteristic (ROC) curves were calculated for MUAC when compared with the WHZ reference criterion.

RESULTS

Of 1161 children, 23.3% were diagnosed with GAM using WHZ, and 4.4% with SAM. Using current WHO cut-offs, the Se of MUAC to identify GAM was greater than for SAM (79 vs. 57%), yet the Sp was lower (84 vs. 97%). From inspection of the ROC curve and Youden Index, Se and Sp were maximised for MUAC < 12.5 cm to identify GAM (Se 79%, Sp 84%), and MUAC < 12.0 cm to identify SAM (Se 88%, Sp 81%).

CONCLUSIONS

The current MUAC cut-off to identify GAM should continue to be used, but when screening for SAM, a higher cut-off could improve case identification. Community screening for SAM could use MUAC < 12.0 cm followed by appropriate treatment based on either MUAC < 11.5 cm or WHZ < −3, as in current practice. While the practicalities of implementation must be considered, the higher SAM MUAC cut-off would maximise early case-finding of high-risk acutely malnourished children.

Severely malnourished children with a low weight-for-height have similar mortality to those with a low mid-upper-arm-circumference: II. Systematic literature review and meta-analysis

BACKGROUND

The WHO recommended criteria for diagnosis of sever acute malnutrition (SAM) are weight-for-height/length Z-score (WHZ) of <- 3Z of the WHO₂₀₀₆ standards, a mid-upper-arm circumference (MUAC) of < 115 mm, nutritional oedema or any combination of these parameters. A move to eliminate WHZ as a diagnostic criterion has been made on the assertion that children with a low WHZ are healthy, that MUAC is a "superior" prognostic indicator of mortality and that adding WHZ to the assessment does not improve the prediction of death. Our objective was to examine the literature comparing the risk of death of SAM children admitted by WHZ or MUAC criteria.

METHODS

We conducted a systematic search for reports which examined the relationship of WHZ and MUAC to mortality for children less than 60 months. The WHZ, MUAC, outcome and programmatic variables were abstracted from the reports and examined. Individual study's case fatality rates were compared by chi-squared analysis and random effects meta-analyses for combined data.

RESULTS

Twenty-one datasets were reviewed. All the patient studies had an ascertainment bias. Most were inadequate because they had insufficient deaths, used obsolete standards, combined oedematous and non-oedematous subjects, did not report the proportion of children with both deficits or the deaths occurred remotely after anthropometry. The meta-analyses showed that the mortality risks for children who have SAM by MUAC < 115 mm only and those with SAM by WHZ < -3Z only are not different.

CONCLUSIONS

As the diagnostic criteria identify different children, this analysis does not support the abandonment of WHZ as an important independent diagnostic criterion for the diagnosis of SAM. Failure to identify such children will result in their being denied treatment and unnecessary deaths from SAM.

Severely malnourished children with a low weight-for-height have a higher mortality than those with a low mid-upper-arm-circumference: III. Effect of case-load on malnutrition related mortality- policy implications

BACKGROUND

Severe acute malnutrition (SAM) is diagnosed when the weight-for-height Z-score (WHZ) is <-3Z of the WHO2006 standards, or a mid-upper-arm circumference (MUAC) of < 115 mm or there is nutritional oedema. Although there has been a move to eliminate WHZ as a diagnostic criterion we have shown that children with a low WHZ have at least as high a mortality risk as those with a low MUAC. Here we take the estimated case fatality rates and published case-loads to estimate the proportion of total SAM related deaths occurring in children that would be excluded from treatment with a MUAC-only policy.

METHODS

The effect of varying case-load and mortality rates on the proportion of all deaths that would occur in admitted children was examined. We used the same calculations to estimate the proportion of all SAM-related deaths that would be excluded with a MUAC-only policy in 48 countries with very different relative case loads for SAM by only MUAC, only WHZ and children with both deficits. The case fatality rates (CFR) are taken from simulations, empirical data and the literature.

RESULTS

The relative number of cases of SAM by MUAC alone, WHZ alone and those with both criteria have a dominant effect on the proportion of all SAM-related deaths that would occur in children excluded from treatment by a MUAC-only program. Many countries, particularly in the Sahel, West Africa and South East Asia would fail to identify the majority of SAM-related deaths if a MUAC only program were to be implemented. Globally, the estimated minimum number of deaths that would occur among children excluded from treatment in our analyses is 300,000 annually.

CONCLUSIONS

The number, proportion or attributable fraction of children excluded from treatment with any change of current policy are the correct indicators to guide policy change. CRFs alone should not be used to guide policy in choosing whether or not to drop WHZ as a diagnostic for SAM. All the criteria for diagnosis of malnutrition need to be retained. It is critical that methods are found to identify those children with a low WHZ, but not a low MUAC, in the community so that they will not remain undetected.

Severely malnourished children with a low weight-for-height have a higher mortality than those with a low mid-upper-arm-circumference: I. Empirical data demonstrates Simpson's paradox

BACKGROUND

According to WHO childhood severe acute malnutrition (SAM) is diagnosed when the weight-for-height Z-score (WHZ) is <-3Z of the WHO2006 standards, the mid-upper-arm circumference (MUAC) is < 115 mm, there is nutritional oedema or any combination of these parameters. Recently there has been a move to eliminate WHZ as a diagnostic criterion on the assertion that children meeting the WHZ criterion are healthy, that MUAC is universally a superior prognostic indicator of mortality and that adding WHZ to the assessment does not improve the prediction; these assertions have lead to a controversy concerning the role of WHZ in the diagnosis of SAM.

METHODS

We examined the mortality experience of 76,887 6-60 month old severely malnourished children admitted for treatment to in-patient, out-patient or supplementary feeding facilities in 18 African countries, of whom 3588 died. They were divided into 7 different diagnostic categories for analysis of mortality rates by comparison of case fatality rates, relative risk of death and meta-analysis of the difference between children admitted using MUAC and WHZ criteria.

RESULTS

The mortality rate was higher in those children fulfilling the WHO2006 WHZ criterion than the MUAC criterion. This was the case for younger as well as older children and in all regions except for marasmic children in East Africa. Those fulfilling both criteria had a higher mortality. Nutritional oedema increased the risk of death. Having oedema and a low WHZ dramatically increased the mortality rate whereas addition of the MUAC criterion to either oedema-alone or oedema plus a low WHZ did not further increase the mortality rate. The data were subject to extreme confounding giving Simpson's paradox, which reversed the apparent mortality rates when children fulfilling both WHZ and MUAC criteria were included in the estimation of the risk of death of those fulfilling either the WHZ or MUAC criteria alone.

CONCLUSIONS

Children with a low WHZ, but a MUAC above the SAM cut-off point are at high risk of death. Simpson's paradox due to confounding from oedema and mathematical coupling may make previous statistical analyses which failed to distinguish the diagnostic groups an unreliable guide to policy. WHZ needs to be retained as an independent criterion for diagnosis of SAM and methods found to identify those children with a low WHZ, but not a low MUAC, in the community.

Concordance between the estimates of wasting measured by weight-for-height and by mid-upper arm circumference for classification of severity of nutrition crisis: analysis of population-representative surveys from humanitarian settings

Background

Despite frequent use of mid-upper arm circumference (MUAC) to assess populations at risk of nutrition emergencies, as well as evidence that measurement of children based on MUAC identifies different children than weight-for-height (WHZ) as wasted, no crisis classification thresholds based on prevalence of wasting by MUAC currently exist.

Methods

We analyzed 733 population-representative anthropometric surveys from 41 countries conducted by Action Contre la Faim (ACF) and the United Nations High Commissioner for Refugees (UNHCR) between 2001 and 2016. Children aged 6–59 months were classified as wasted if they had a WHZ < − 2 and/or a MUAC < 125 mm. Prevalence of wasting as assessed by WHZ and by MUAC were compared using correlations and linear regression models adjusting for stunting prevalence, sex and age distribution of the sample. Median prevalence of wasting by MUAC corresponding to each of the WHZ-based crisis thresholds was examined.

Results

Median prevalence of wasting by WHZ was 10.47% (IQR: 6.34–17.55%) and by MUAC was 6.66% (IQR:4.12–10.88%). Prevalence of wasting by WHZ exceeded prevalence by MUAC in 543 (74.1%) surveys and median prevalence by WHZ was greater in 30 (73.17%) countries. Prevalence of wasting by WHZ is poorly correlated with prevalence of wasting by MUAC (ρ = 0.55). R² was 0.36 for unadjusted and 0.45 for adjusted linear regression model. The difference between the prevalence by WHZ and by MUAC increased as the overall prevalence by WHZ increased (ρ = 0.69). Surveys with prevalence of wasting by WHZ approximately equal to thresholds for “poor” (5% ± 2.5%), “serious” (10% ± 2.5%), “emergency” (15% ± 2.5%), and “famine” (30% ± 2.5%) were observed to have median prevalence of wasting by MUAC of 4.51% (IQR: 2.73–6.81%), 6.67% (IQR: 4.27–10.03%), 8.15% (IQR: 5.11–11.86%), and 15.71% (IQR: 10.28–17.50%), respectively. There was a very substantial overlap of MUAC values across the threshold categories.

Conclusions

Given a poor correlation between population prevalence of wasting by WHZ and by MUAC, classification of surveys based on prevalence of wasting by MUAC will result in poor concordance with current WHZ-based crisis thresholds, even if regional differences are considered, regardless of the cutoffs used.

MUAC-for-age more useful than absolute MUAC for nutritional surveillance in Somalia: results from nineteen cross-sectional surveys (2007-2016)

BACKGROUND

Somalia is affected by a civil war and a protracted humanitarian crisis for more than two decades. The international community has put in place nutrition surveillance systems to monitor the situation and inform decisions. However, the indicators commonly used to identify acute malnutrition, weight-for-height Z-score (WHZ) and mid upper arm circumference (MUAC), do not always converge in their estimations of acute malnutrition, creating challenges for decision making. Furthermore, the divergences are not consistent across livelihood populations within the country. We explored the MUAC-for-age Z-score (MUACAZ) as an alternative indicator in Somalia to minimize the discrepancy.

METHODS

We analyzed data from nineteen cross-sectional surveys conducted in Somalia between 2007 and 2016. We compared the acute malnutrition prevalence estimates by each of the indicators and the degree of overlap in the individual diagnosis of acute malnutrition between the WHZ and the MUAC-based indicators. We performed multivariate regression analysis with sex, age and stunting as independent variables and acute malnutrition as the dependent outcome, defined by WHZ, MUAC or MUACAZ. We performed all the analysis in the population overall and in each of the livelihood populations separately.

RESULTS

A total 255,623 measurements of children 6-59 months of age were analyzed. The overall prevalence of global acute malnutrition by MUACAZ (15.8%) was similar to the one obtained using WHZ (16%), whereas prevalence based on MUAC was much lower (7.8%). These patterns of divergence were sustained throughout the nineteen surveys and the livelihoods studied, with only few exceptions. However, the proportion of overlap in the individual diagnosis of children as acutely malnourished was low between WHZ and absolute MUAC diagnosis (18.1%) and also between WHZ and MUACAZ (28.3%). Results show that age, sex and stunting status of the child affected the likelihood of being diagnosed as acutely malnourished to varying degrees, depending on the indicator used.

CONCLUSIONS

The MUAC-for-age (MUACZ) indicator yielded acute malnutrition prevalence estimates convergent with those obtained by WHZ indicator. However, the degree of overlap between these two indicators for individual diagnosis of acute malnutrition is low. Further studies of MUACAZ as an alternative indicator for nutrition surveillance are needed.

Mid-upper arm circumference in detection of weight-for-height Z-score below -3 in children aged 6-59 months

OBJECTIVE

To evaluate the predictive ability of mid-upper arm circumference (MUAC) for detecting severe wasting (weight-for-height Z-score (WHZ) <-3) among children aged 6-59 months.

DESIGN

Cross-sectional survey.

SETTING

Rural Uttar Pradesh, India.

SUBJECTS

Children (n 18 456) for whom both WHZ (n 18 463) and MUAC were available.

RESULTS

The diagnostic test accuracy of MUAC for severe wasting was excellent (area under receiver-operating characteristic curve = 0·933). Across the lower range of MUAC cut-offs (110-120 mm), specificity was excellent (99·1-99·9 %) but sensitivity was poor (13·4-37·2 %); with higher cut-offs (140-150 mm), sensitivity increased substantially (94·9-98·8 %) but at the expense of specificity (37·6-71·9 %). The optimal MUAC cut-off to detect severe wasting was 135 mm. Although the prevalence of severe wasting was constant at 2·2 %, the burden of severe acute malnutrition, defined as either severe wasting or low MUAC, increased from 2·46 to 17·26 % with cut-offs of <115 and <135 mm, respectively. An MUAC cut-off <115 mm preferentially selected children aged ≤12 months (OR=11·8; 95 % CI 8·4, 16·6) or ≤24 months (OR=23·4; 95 % CI 12·7, 43·4) and girls (OR=2·2; 95 % CI 1·6, 3·2).

CONCLUSIONS

Based on important considerations for screening and case detection in the community, modification of the current WHO definition of severe acute malnutrition may not be warranted, especially in the Indian context.

Children with Moderate Acute Malnutrition with No Access to Supplementary Feeding Programmes Experience High Rates of Deterioration and No Improvement: Results from a Prospective Cohort Study in Rural Ethiopia

BACKGROUND

Children with moderate acute malnutrition (MAM) have an increased risk of mortality, infections and impaired physical and cognitive development compared to well-nourished children. In parts of Ethiopia not considered chronically food insecure there are no supplementary feeding programmes (SFPs) for treating MAM. The short-term outcomes of children who have MAM in such areas are not currently described, and there remains an urgent need for evidence-based policy recommendations.

METHODS

We defined MAM as mid-upper arm circumference (MUAC) of ≥11.0 cm and <12.5 cm with no bilateral pitting oedema to include Ethiopian government and World Health Organisation cut-offs. We prospectively surveyed 884 children aged 6-59 months living with MAM in a rural area of Ethiopia not eligible for a supplementary feeding programme. Weekly home visits were made for seven months (28 weeks), covering the end of peak malnutrition through to the post-harvest period (the most food secure window), collecting anthropometric, socio-demographic and food security data.

RESULTS

By the end of the study follow up, 32.5% (287/884) remained with MAM, 9.3% (82/884) experienced at least one episode of SAM (MUAC <11 cm and/or bilateral pitting oedema), and 0.9% (8/884) died. Only 54.2% of the children recovered with no episode of SAM by the end of the study. Of those who developed SAM half still had MAM at the end of the follow up period. The median (interquartile range) time to recovery was 9 (4-15) weeks. Children with the lowest MUAC at enrolment had a significantly higher risk of remaining with MAM and a lower chance of recovering.

CONCLUSIONS

Children with MAM during the post-harvest season in an area not eligible for SFP experience an extremely high incidence of SAM and a low recovery rate. Not having a targeted nutrition-specific intervention to address MAM in this context places children with MAM at excessive risk of adverse outcomes. Further preventive and curative approaches should urgently be considered.

Short children with a low midupper arm circumference respond to food supplementation: an observational study from Burkina Faso

BACKGROUND

The management of children with moderate acute malnutrition (MAM) is based on food supplementation in outpatient programs. When midupper arm circumference (MUAC) is used as the sole admission criterion, it is common practice to exclude children with lengths <67 cm from treatment. The WHO calls for research to determine the treatment effect among children with MAM included by MUAC and aged ≥6 mo with lengths <67 cm.

OBJECTIVE

We hypothesized that among children given supplementary feeding based on an MUAC of 115-124 mm as the sole criterion, there would be no difference in growth rate between children <67 cm and those ≥67 cm in length at program admission.

DESIGN

This was an observational study nested in a randomized trial that investigated the effectiveness of new formulations of corn-soy blend and lipid-based nutrient supplements. Children aged 6-23 mo were included if their MUAC was between 115 and 124 mm but with a weight-for-height z score (WHZ) ≥-2. This cohort was divided into 2 groups by length at admission: <67 cm ("short") and ≥67 cm ("long"). Linear mixed-effects models and regression models were used to compare gains in weight and MUAC while adjusting for intervention, season, sex, age, and site.

RESULTS

Weight-gain velocity (expressed as g · kg(-1) · d(-1)) and MUAC-gain velocity (expressed as 0.01 mm · cm(-1) · d(-1)) were not different between short and long children. Weight-gain velocity was slightly higher in the shortest quartile of length (P = 0.03), whereas there was no effect modification by stunting across length quartiles (P = 0.32).

CONCLUSIONS

We found no evidence of a difference in percentage of weight gain or weight-gain velocity during supplementary feeding in short or long children aged 6-23 mo. We recommend a policy change to include children <67 cm in supplementary feeding programs if their MUAC is between 115 and 124 mm and their WHZ is ≥-2. This could benefit millions of children currently excluded from supplementary feeding. This trial was registered at www.controlled-trials.com as ISRCTN42569496.