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Clinical Nutrition 39 (2020) 3512e3519

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Clinical Nutrition

journal homepage: http://www.elsevier.com/locate/clnu

Original article

Vitamin A and iron status of children before and after treatment ofuncomplicated severe acute malnutrition

Suvi T. Kangas a, b, *, C�ecile Salp�eteur b, Victor Niki�ema c, Leisel Talley d, Andr�e Briend a, e,Christian Ritz a, Henrik Friis a, Pernille Kaestel a

a Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmarkb Expertise and Advocacy Department, Action Against Hunger (ACF), Paris, Francec Nutrition and Health Department, Action Against Hunger (ACF) Mission, Burkina Fasod Centers for Disease Control and Prevention, Atlanta, GA, USAe Center for Child Health Research, University of Tampere School of Medicine, Tampere University, FIN-33014, Tampere Finland

a r t i c l e i n f o

Article history:Received 15 January 2020Accepted 10 March 2020

Keywords:Vitamin AIronMicronutrientSevere acute malnutritionChildrenReady-to-use therapeutic food

* Corresponding author. Expertise and AdvocacyHunger (ACF), 14/16 Boulevard Douaumont – CS 80France.

E-mail address: [email protected] (S.T. Ka

https://doi.org/10.1016/j.clnu.2020.03.0160261-5614/© 2020 The Author(s). Published by Elsevie

s u m m a r y

Background & aims: Treatment of children with uncomplicated severe acute malnutrition (SAM) is basedon ready-to-use therapeutic foods (RUTF) and aims for quick regain of lost body tissues while providingsufficient micronutrients to restore diminished body stores. Little evidence exists on the success of thetreatment to establish normal micronutrient status. We aimed to assess the changes in vitamin A andiron status of children treated for SAM with RUTF, and explore the effect of a reduced RUTF dose.Methods: We collected blood samples from children 6e59 months old with SAM included in a rando-mised trial at admission to and discharge from treatment and analysed haemoglobin (Hb) and serumconcentrations of retinol binding protein (RBP), ferritin (SF), soluble transferrin receptor (sTfR), C-reac-tive protein (CRP) and a1-acid glycoprotein (AGP). SF, sTfR and RBP were adjusted for inflammation (CRPand AGP) prior to analysis using internal regression coefficients. Vitamin A deficiency (VAD) was definedas RBP < 0.7 mmol/l, anaemia as Hb < 110 g/l, storage iron deficiency (sID) as SF < 12 mg/l, tissue irondeficiency (tID) as sTfR > 8.3 mg/l and iron deficiency anaemia (IDA) as both anaemia and sID. Linear andlogistic mixed models were fitted including research team and study site as random effects and adjustingfor sex, age and outcome at admission.Results: Children included in the study (n ¼ 801) were on average 13 months of age at admission totreatment and the median treatment duration was 56 days [IQR: 35; 91] in both arms. Vitamin A and ironstatus markers did not differ between trial arms at admission or at discharge. Only Hb was 1.7 g/l lower(95% CI �0.3, 3.7; p ¼ 0.088) in the reduced dose arm compared to the standard dose, at recovery. Meanconcentrations of all biomarkers improved from admission to discharge: Hb increased by 12% or 11.6 g/l(95% CI 10.2, 13.0), RBP increased by 13% or 0.12 mmol/l (95% CI 0.09, 0.15), SF increased by 36% or 4.4 mg/l(95% CI 3.1, 5.7) and sTfR decreased by 16% or 1.5 mg/l (95% CI 1.0, 1.9). However, at discharge, micro-nutrient deficiencies were still common, as 9% had VAD, 55% had anaemia, 35% had sID, 41% had tID and21% had IDA.Conclusion: Reduced dose of RUTF did not result in poorer vitamin A and iron status of children. Onlyhaemoglobin seemed slightly lower at recovery among children treated with the reduced dose. Whileimprovement was observed, the vitamin A and iron status remained sub-optimal among children treatedsuccessfully for SAM with RUTF. There is a need to reconsider RUTF fortification levels or test otherpotential strategies in order to fully restore the micronutrient status of children treated for SAM.© 2020 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND

license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Department, Action Against060, 75854 Paris Cedex 17,

ngas).

r Ltd. This is an open access article

1. Introduction

Severe acute malnutrition (SAM), defined as severe wasting, lowmid-upper arm circumference (MUAC) and/or oedema, is wide-spread among children in low-income countries. While incidence

under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Abbreviations

AGP a1-acid glycoproteinCMAM community-based management of acute

malnutritionCRP C-reactive proteinHb haemoglobinIDA iron deficiency anaemiaMAM moderate acute malnutritionMUAC mid-upper arm circumferenceRBP retinol binding proteinRUTF ready-to-use therapeutic foodSAM severe acute malnutritionSF serum ferritinsID storage iron deficiencytID tissue iron deficiencysTfR soluble transferrin receptorVAD vitamin A deficiencyWHO World Health OrganisationWHZ weight-for-height z-score

S.T. Kangas et al. / Clinical Nutrition 39 (2020) 3512e3519 3513

data are lacking, the number of children with severe wasting alone,at any time, was estimated at 16.6 million children in 2018 [1]. Thetreatment of SAM without medical complications consists of ready-to-use-therapeutic food (RUTF) and one week of antibiotic treat-ment [2]. RUTFs are fortified energy-dense pastes designed to fulfilall the nutritional needs of children during recovery from SAM [3].The aim of the treatment is to enable a rapid regain of lost bodytissues while providing sufficient micronutrients to restorediminished body stores. However, little evidence exists on thesuccess of the treatment to restore sufficient micronutrient statusby recovery.

Vitamin A deficiency (VAD) affects 190 million children under 5years of age worldwide and is associated with increased risk ofmorbidity and mortality, and in the most severe form can lead toblindness [4]. In Brazil 41.2% and in Congo up to 98% of hospitalisedmalnourished children had VAD [5,6]. RUTFs contain 0.7e1.0 mg ofvitamin A per 92 g sachet [3] and each child typically receives 2e3sachets per day, which translates to 3e8 times the daily recom-mended intake of 0.4 mg for healthy children in this age group [7].However, no data exist on the vitamin A status of children withuncomplicated SAM at admission to and discharge fromcommunity-based treatment. Ensuring a normal vitamin A statusby discharge would seem crucial, considering its role in healthygrowth [8e10].

Similarly, anaemia and iron deficiency are common world-wide; WHO estimates that nearly half of all children under 5 yearsof age are anaemic and/or iron deficient [11]. Iron deficiency inchildhood is associated with impaired growth and development[12,13]. Previous studies on children with SAM have reported highprevalence of anaemia at admission: up to 95% in inpatient set-tings in India [14,15], 80% in Burkina Faso [16], and 49% amonguncomplicated cases in Malawi [17]. RUTFs contain 9e11 mg ofiron per sachet [3] with 2 sachets equalling the daily recom-mended intake of 18.6 mg (assuming a low bioavailability) forhealthy children [7]. A study in Malawi showed that 25% of chil-dren were still anaemic when discharged from SAM treatment[17]. Additionally, they observed that the proportion of childrenwith iron deficiency (defined as soluble transferrin receptorconcentrations > 8.3 mg/l when adjusted for inflammation) didnot decrease from admission (56%) to discharge (58%). Doc-umenting the response to SAM treatment in different contexts

would be important in order to guide possible protocol revisionsaimed at improving the iron status of treated children.

The objective of this paper is to assess the change in vitamin Aand iron status of children treated for uncomplicated SAM withRUTF, and explore the effect of a reduced RUTF dose on the vitaminA and iron status of recovered children.

2. Methods

2.1. Study area and participants

This study was a cohort study nested in to the MANGO study, arandomised non-inferiority trial testing the efficacy of a reducedRUTF dose compared to standard RUTF dose in the treatment ofuncomplicated SAM among children 6e59 months of age [18]. Wepreviously reported a non-inferior weight gain velocity [18] and asimilar tissue gain pattern (in press) with a reduced RUTF dosecompared to the standard dose.

The study was conducted from October 2016 to December 2018in the east of Burkina Faso, where the prevalence of wasting was10% in 2016 [19]. Intestinal parasites are common with 86% ofschool age children in neighbouring regions infected [20] and up to16% are estimated to present with haemoglobinopathies [21]. Six-monthly vaccination campaigns with vitamin A supplementation(100 000 IU to 6e11 month olds; 200 000 IU to 12e59 month olds)were organised in the area throughout the study period. Commu-nity and health centre level sensitisation on appropriate infant andyoung child feeding (IYCF) practices including promotion of the useof fortified infant flours were supported by various NGOs workingin the area.

As described previously [18], participants were recruited at 10health centres. Eligibility criteria consisted of having a weight-for-height z-score (WHZ) < �3 and/or a MUAC < 115 mm, no oedemaand the absence of medical complications as per the nationalprotocol [22]. Children failing the appetite test, having receivedSAM treatment in the past 6 months, with known peanut or milkallergy, disability affecting food intake or whose caregiver wereunable to comply with the weekly visit schedule were excluded.

2.2. Randomisation and study procedures

For a full description of the methodology, please refer to Ref.[18]. In brief, after obtaining caregiver consent, children wererandomised individually to receiving either a standard dose of RUTFthroughout treatment or a reduced dose of RUTF from the 3rdtreatment week onwards (Table 1). The vitamin A and iron contentper daily dose and per arm is described in Table 1. The content hasbeen calculated based on RUTF nutrient specifications [3]. Medicaltreatment was provided for all children per the national protocol[22] including a 7-day course of amoxicillin at admission(50e100 mg/kg/d) and albendazole at the second treatment visitfor children � 12 months of age (200 mg to 12e23-month-olds;400 mg to �24-month-olds). Any missed routine vaccinations or 6-monthly vitamin A supplementations were caught-up at admis-sion. Children were treated until reaching anthropometric recoverycriteria or until defaulting from treatment, being transferred toinpatient care, diseased or declared non-responding after amaximum of 16 weeks of treatment. Anthropometric recovery wasdefined as a WHZ � �2 for those admitted with a WHZ < �3 only,MUAC � 125 mm for those admitted with a MUAC < 115 mm only,or WHZ � �2 and MUAC � 125 mm for those admitted withWHZ < �3 and MUAC < 115 mm, on two consecutive visits andabsence of any illness.

Venous blood was collected in Vacutainer® (BD, New Jersey,USA) clot activator tubes at admission and at discharge from

Table 1Vitamin A and iron content per daily RUTF dose with reduced and standard dose.

Weight (kg) Standard RUTF dosea Reduced RUTF dosea

RUTF quantity/day(sachets)

Vitamin A/daily RUTFdose (mg)

Iron/daily RUTFdose (mg)

RUTF quantity/day(sachets)

Vitamin A/dailyRUTF dose (mg)

Iron/daily RUTFdose (mg)

3.0e3.4 1.1 1.1 11.4 1.0 1.0 10.03.5e4.9 1.4 1.4 14.3 1.0 1.0 10.05.0e6.9 2.1 2.1 21.4 1.0 1.0 10.07.0e9.9 2.9 2.9 28.6 2.0 2.0 20.010.0e14.9 4.3 4.3 42.9 2.0 2.0 20.0

RUTF, ready-to-use therapeutic foods.a Reduced dose arm received a standard dose of RUTF for the first 2 weeks and then the reduced dose from 3rd treatment week onwards.

S.T. Kangas et al. / Clinical Nutrition 39 (2020) 3512e35193514

treatment. Two attempts were made for blood collection from atotal of 3 possible sites. If infeasible, a finger prick was used for arapid diagnostic test for malaria (SD Bioline, Abbott, Illinois, USA)and to measure Hb with a HemoCue® 301 device (Hemocue AB,Sweden). The accuracy of the HemoCue® was monitored monthlyusing commercial controls (Eurotrol, Kentucky, USA) and the valueswere within certified values. Blood samples were transported in acold box at 2e8 �C to the field laboratory where samples werestored in a fridge at 2e10 �C for maximum 24 h. Serum was isolatedfollowing centrifugation at 3000 rotations per minute for 5 min(EBA 20 S Hettich, Germany) and stored at �20 �C until shipment toVitMin Lab in Willstaedt, Germany for analysis. Serum ferritin (SF),soluble transferrin receptor (sTfR), retinol binding protein (RBP), C-reactive protein (CRP), a1-acid glycoprotein (AGP), were deter-mined using a combined sandwich enzyme linked immunosorbentassay [23].

A thorough medical history and evaluation of morbidities wasperformed by a study nurse at admission and at each weekly visit.Fever was defined as an arm pit temperature of �37.5 �C and ledsystematically to rapid testing for malaria with a positive resultdefining malaria. Acute respiratory illness (ARI) was defined ascough reported by caregiver in the past week or diagnosed by studynurse during visit. Diarrhoea included acute, persistent or dysen-teric forms and was defined as 3 or more loose stools per day asreported by caregiver in the past week or diagnosed by study nurse.Medical treatment offered included a 3-day course of arthemeter(2 � 20 mg/d) and lumefantrine (2 � 120 mg/d) in case of malariaand a 7-day course of amoxicillin (50e100 mg/kg/d) in case of ARIor diarrhoea.

2.3. Outcomes and adjustment for inflammation

As SF, sTfR and RBP are affected by inflammation they wereadjusted prior to analysis using internal regression coefficients aspreviously described [24e26]. Log-transformation was applied forRBP, SF, sTfR, CRP and AGP due to non-normal distribution. Thecoefficients were 0.178 for log transformed CRP (logCRP) and 0.167for log transformed AGP (logAGP) when adjusting log transformedSF, 0.004 for logCRP and 0.228 for logAGP when adjusting logtransformed sTfR and �0.071 for logCRP and �0.028 for logAGPwhen adjusting log transformed RBP. Based upon recommenda-tions from the BRINDA study group [24e26], adjustments were notapplied below first deciles of CRP and AGP corresponding to0.20 mg/l for CRP and 0.43 g/l for AGP in the current data.

Anaemia was defined as Hb < 110 g/L [27], storage iron defi-ciency (sID) as inflammation adjusted SF (SFadj) < 12 mg/L [28],tissue iron deficiency (tID) as inflammation adjusted sTfR >8.3 mg/land iron-deficiency anaemia (IDA) as Hb < 110 g/L and SFadj < 12 mg/L. Vitamin A deficiency (VAD) was defined as inflammationadjusted RBP <0.7 mmol/l. For descriptive purposes, inflammationcategories were defined as proposed by Thurnham et al. [29].

2.4. Statistical analysis

Data were collected via tablets using Open Data Kit software. Allstatistical analyses were carried out using Stata 15 (Stata Corp,Texas, USA). Characteristics of the study population were summa-rized as percentages and means ±SDs or, if not normally distributedas median (IQR). Linear and logistic mixed models were used toassess differences in means and proportions at admission, withstudy team and health centre included as random effects.

Linear and logistic mixed models were used to evaluate changefrom admission to discharge in mean biomarker concentrations orproportions of deficiencies, as appropriate. Study team, healthcentre, and child id were included as random effects. Both unad-justed and adjusted models (including sex and age) were fitted.Similarly, the effect of RUTF dose on mean biomarker concentra-tions and proportions of deficiencies were analysed with linear andlogistic mixed models. Study team and health centre were includedin the models as random effects. Unadjusted and adjusted models(including sex, age, and outcome measure at admission) werefitted.

Results were presented as estimated mean differences with 95%CI in means and proportions. Right-skewed outcomes werelogarithm-transformed prior to analysis. Subsequently, backtransformation was applied to log transformed variables to esti-mate mean differences in original units [30]. Model checking wasbased on residual and normal probability plots.

2.5. Ethical considerations

Children not included in the study but diagnosed with SAMwere referred to standard care at the health centre. Children whodid not recover from SAM within 16 weeks of treatment weresubsequently referred to standard care. The study was carried outin accordance with the Declaration of Helsinki. Field registries werekept in a locked facility. The study was approved by the nationalEthics Committee of Burkina Faso (deliberation number 2015-12-00) and the national clinical trials board of Burkina Faso (DirectionG�en�erale de la Pharmacie, du M�edicament et des Laboratoires(DGPML)). The trial was registered in the International StandardRandomized Controlled Trial Number (ISRCTN) registry asISRCTN50039021.

3. Results

Out of the total 801 children included in the trial, 402 wererandomised to the reduced RUTF dose and 399 to the standarddose. Hb was analysed for all admitted children and additionalbiomarkers including SF, sTfR, RBP, CRP and AGP were analysed for714 (89%) of admitted children. At discharge, we analysed Hb for425 (98%) of recovered children and additional biomarkers wereanalysed for 383 (90%) of recovered children (see Fig. 1).

S.T. Kangas et al. / Clinical Nutrition 39 (2020) 3512e3519 3515

As previously detailed [18], non-recovered children representeda heterogeneous group of children referred to inpatient care (20%),defaulters (12%), lost to follow-up (0.1%), deaths (0.1%), non-responders (13%) and false discharges (3%). Because of ethical andoperational constraints, vitamin A and iron biomarker data wereonly obtained from 30% of these children, mostly from the non-responders.

Baseline characteristics of children did not differ between thestudy groups in terms of morbidity, inflammatory markers, andvitamin A and iron status markers (Table 2). For the full cohort, themean age was 13.4 months at admission and 49% were male.Approximately 78% of children reported or were diagnosed with anillness at admission with 33% presenting with positive malariarapid test. Most children had elevated serum CRP (42%) or AGP(64%) at admission. The median length of stay in treatment was 56days [IQR: 35; 91] in both arms.

Mean concentrations of all vitamin A and iron status biomarkersimproved from admission to discharge: Hb increased by 12%, RPBby 12% and SF by 36% while sTfR decreased by 16%. These changesresulted in fewer children being under the deficiency cut-offs atdischarge (Table 3). Vitamin A deficiency (RBP < 0.7 mmol/l)decreased from 25% at admission to 9% at discharge (Fig. 2).Anaemia (Hb < 110 g/l) decreased from 77% at admission to 55% atdischarge. Storage iron deficiency (SF < 12 mg/l) decreased from 50%at admission to 35% at discharge. Tissue iron deficiency(sTfR > 8.3 mg/l) decreased from 55% at admission to 41% atdischarge. Iron deficiency anaemia decreased from 42% at admis-sion to 21% at discharge.

At recovery, no differences were found in the mean concentra-tions of RBP, SF or sTfR or on the percentages of VAD, sID, tID or IDAbetween the study arms (Table 4). However, the reduced dose wasassociated with a 1.7 g/l lower haemoglobin concentration and 9%higher anaemia prevalence, although these differences were only

Table 2Characteristics of children at admission to SAM treatment receiving a reduced or a stand

Characteristics n Red

Age, months 801 13.Male, % 801 49.Morbidity

Any illness, % 801 79Malaria, % 801 33Acute respiratory illness, % 801 31Diarrhoea, % 801 25Other, % 801 11Fever, % 801 27

InflammationC-reactive protein (CRP), mg/l 714 2.5>5 714 41

a1-acid glycoprotein (AGP), g/l 714 1.3>1 714 62

Inflammation categoriesCRP � 5 mg/l and AGP � 1 g/l 714 33CRP > 5 mg/l and AGP � 1 g/l 714 5 (1CRP > 5 mg/l and AGP > 1 g/l 714 36CRP � 5 mg/l and AGP > 1 g/l 714 26

Vitamin A and ironRetinol binding protein, mmol/l 714 0.8<0.7 mmol/l, % 714 26

Haemoglobin, g/l 801 96.<110 g/l, % 801 78

Ferritin, mg/l 714 11.<12 mg/l, % 714 52

Soluble transferrin receptor, mg/l 714 9.0>8.3 mg/l, % 714 55

Iron deficiency anaemia, % 714 43

Data are mean ± SD, median [IQR] or proportion (n) with p-value for difference using logRUTF, ready-to-use therapeutic food.

marginally significant. Similar results were found when includingall discharge categories as opposed to only recovered (S1 Table) orwithout adjustments for age, sex and outcome measure atadmission.

4. Discussion

In this study, a high proportion of children with SAM had sub-optimal vitamin A and iron status at admission and these de-ficiencies were only partly corrected by discharge with 56%anaemic, 21% IDA and 9% VAD. There was no difference in meanRBP, SF or sTfR at discharge between children who had received thereduced and the standard RUTF dose. However, the mean Hb con-centration was slightly lower in children receiving the reducedcompared to standard dose, although this difference was onlymarginally significant.

High rates of anaemia have been reported in previous studiesamong malnourished children [17,31,32], however few have re-ported change during treatment. In our study, anaemia decreasedsignificantly from 78% to 56%, similarly to Cichon's observationamong children with MAM treated for 12 weeks where anaemiadecreased from 70% at admission to 53% at discharge [31].

Iron deficiency explains only half of the anaemia; 40% were IDAwhile 78% were anaemic at admission, and 21% were IDA and 56%anaemic at discharge. RUTFs contain many nutrients such as vita-mins A, C, D, E, B2, B6, B12, folate, copper and zinc, whose defi-ciency can cause anaemia [33e39]. Thus, treatment with RUTFcould correct nutritional anaemia not caused by iron deficiency. Yet,haemoglobinopathies and inflammation may also cause anaemia[36], meaning nutritional supplementation may not fully correct it.

We observed a trend towards 1.7 g/l lower mean Hb and 9-percentage points more anaemia among children who receivedthe reduced compared to standard RUTF dose. A similar trend was

ard RUTF dose.

uced RUTF Standard RUTF p-value

3 ± 8.6 13.4 ± 8.9 0.795 (199) 49.4 (197) 0.97

(316) 78 (311) 0.82(134) 32 (129) 0.75(126) 31 (125) 0.94(101) 25 (99) 0.93(45) 13 (53) 0.34(108) 25 (100) 0.57

[0.6e12.6] 3.3 [0.7e13.2] 0.59(149) 42 (150) 0.74[0.8e1.9] 1.3 [0.8e2.0] 0.19(225) 65 (229) 0.48

(118) 31 (111) 0.728) 4 (13) 0.39(131) 39 (137) 0.49(94) 26 (92) 0.99

8 [0.70e1.12] 0.90 [0.71e1.11] 0.94(93) 25 (87) 0.736 ± 16.9 94.7 ± 17.8 0.11(314) 79 (314) 0.854 [5.1e31.6] 12.9 [5.1e31.2] 0.58(187) 48 (168) 0.26[6.4e13.8] 9.3 [6.5e14.2] 0.50(200) 57 (200) 0.76(156) 40 (141) 0.37

istic or linear mixed models with study site and research team as random variables.

Table 3Change in vitamin A and iron status biomarkers from admission to discharge from SAM treatment.

Outcome Admission Discharge Changea

n values n values mean (95% CI) p-value

RBP, mmol/l 714 0.89 [0.70e1.11] 473 1.00 [0.83e1.21] 0.12 (0.09; 0.15) <0.001Hb, g/l 801 95.7 ± 17.4 537 106.8 ± 13.5 11.6 (10.1; 13.0) <0.001SF, mg/l 714 12.1 [5.1e31.6] 474 16.1 [9.6e28.6] 4.4 (3.1; 5.7) <0.001sTfR, mg/l 714 9.2 [6.5e14.1] 474 7.8 [6.3e10.7] �1.5 (�1.9; �1.0) <0.001

Values are median [IQR] for RBP, SF and sTfR and mean ± SD for Hb.RBP, retinol binding protein adjusted for inflammation; Hb, haemoglobin; SF, serum ferritin adjusted for inflammation; sTfR, soluble transferrin receptor adjusted forinflammation.

a Change in concentrations when adjusting for sex and age and using linear mixed models with id, study site and research team as random effects.

Fig. 1. Patient flow chart. * including serum ferritin (SF), soluble transferrin receptor (sTfR), retinol binding protein (RBP), C-reactive protein (CRP), a1-acid glycoprotein (AGP). Hb,haemoglobin; RUTF, ready-to-use therapeutic food.

Fig. 2. Deficiencies in vitamin A and iron status biomarkers at admission to anddischarge from SAM treatment. Data are means with 95% CI when using logistic mixedmodels including study team, health centre and id as random factors and adjusting forsex and age. VAD: vitamin A deficiency defined as retinol binding protein adjusted forinflammation < 0.7 mmol/l; sID: storage iron deficiency defined as serum ferritinadjusted for inflammation < 12 mg/l; tID: tissue iron deficiency defined as solubletransferrin receptor adjusted for inflammation > 8.3 mg/l; IDA: iron deficiencyanaemia defined as haemoglobin < 110 g/l and serum ferritin adjusted forinflammation < 12 mg/l.

S.T. Kangas et al. / Clinical Nutrition 39 (2020) 3512e35193516

not observed in SF nor sTfR. The observed effect on Hb might be dueto other micronutrients in the RUTF that, when given at smallerquantities, become insufficient to correct low Hb.

While we observed a favourable change in all iron statusmarkers, it was insufficient to achieve normal values upondischarge. In Malawi non-standard formulations of RUTF were

tested including three times the iron of the standard RUTF [17]. Thealternative formulations led to significantly lower rate of anaemiaby discharge; 12e18% compared to 25% with standard RUTF [17].These results combined with our observation of high rates ofanaemia and iron deficiency at discharge from standard treatmentsuggest that children with SAM might benefit from RUTF formu-lations with higher iron content. Currently, a sachet of RUTF con-tains 9e11 mg of iron with 2e3 sachets providing a maximum oftwice the recommended daily intake (12e19 mg/d) of a healthy7e59 month old child [7]. Most of the iron requirements for chil-dren under 3 years of age are related to growth [7]. Childrenrecovering from malnutrition, with an estimated weight gain ve-locity 3e5 times higher [40] than normal children [41], would beexpected to have proportionally high iron requirements. This said,it is usually accepted that correcting iron deficiency takes 3e6months [42,43] and therefore post-discharge interventionsdesigned to correct the remaining micronutrient deficienciesshould be considered.

However, iron interventions raise several issues. First, potentialeffects of additional iron on morbidity should be investigated asiron can increase the risk and severity of diarrhoea, fever, vomitingand hospitalisations [44e47]. Second, additional iron might have anegative effect on the microbiota [47e50] that is already altered inmalnourished children [51,52]. Third, additional iron might nega-tively affect growth especially among iron replete children[44,53e55]. Slower weight gain velocity was also observed in theMalawian study among children with SAM receiving RUTF withhigher than standard iron content [56]. Fourth, high iron content in

Table 4Vitamin A and iron status at discharge among children recovered from SAM and treated with a reduced or a standard RUTF dose.

Outcome n Reduced RUTF dose Standard RUTF dose Differencea

mean (95% CI) p-value

RBP, mmol/l 382 0.99 [0.83e1.23] 0.99 [0.83e1.17] 0.02 (�0.03; 0.08) 0.38<0.7 mmol/l, % 382 10 (18) 9 (17) 0 (�5; 4) 0.87

Hb, g/l 425 107.1 ± 11.8 108.6 ± 11.2 �1.7 (�3.7; 0.3) 0.088<110 g/l, % 425 59 (124) 51 (110) 9 (�1; 19) 0.074

SF, mg/l 383 16.1 [9.4e27.2] 16.5 [10.0e28.4] 0.8 (�1.8; 3.3) 0.56<12 mg/l, % 383 36 (69) 31 (60) 2 (�8; 13) 0.65

sTfR, mg/l 383 7.8 [6.4e11.2] 8.1 [6.4e10.8] �0.1 (�0.8; 0.7) 0.82>8.3 mg/l, % 383 43 (82) 43 (83) �3 (�13; 8) 0.63

IDA, % 376 23 (43) 19 (35) 1 (�7; 9) 0.75Values are median [IQR] for RBP, SF and sTfR, mean ± SD for Hb and proportions (n).RBP, retinol binding protein adjusted for inflammation; Hb, haemoglobin; SF, serum ferritin adjusted for inflammation; IDA, iron deficiency anaemia (defined as Hb < 110 g/land SF < 12 mg/l); sTfR, soluble transferrin receptor adjusted for inflammation.

a Difference when adjusting for age, sex and outcome measure at admission using linear and logistic mixed models including research team and study site as random factors.

S.T. Kangas et al. / Clinical Nutrition 39 (2020) 3512e3519 3517

infant formula has been associated with impairment of cognitivedevelopment [57,58]. Finally, additional iron could interfere withthe absorption of other trace elements such as copper and zinc[59e62]. The choice of the form of iron would also be crucial inminimising the harmful and maximising the positive effects [63].

To our knowledge this is the first study reporting the response ofvitamin A status to treatment with RUTF of children with uncom-plicated SAM; VAD decreased from 25% at admission to 9% atdischarge. Previous studies conducted in inpatient settings havereported high rates of VAD; 41% in Brazil [5] and 81% in Bangladesh[64] had VAD. However, neither study adjusted serum retinol forinflammation and therefore may have overestimated VAD preva-lence [65].

That 9% of children remained VAD while discharged as recov-ered from SAM deserves attention. This was observed despite dailyRUTF intake for a mean duration of 2 months and in the context oftwice a year high-dose vitamin A supplementation campaigns. The16-percentage point decrease in VAD during treatment reflects aneffective response to RUTF, but the question remains whether ahigher vitamin A fortification level of RUTF could eliminate VAD. Asub-optimal vitamin A status is also related to anaemia and irondeficiency and thus eradicating VAD might also help in furtherdecreasing anaemia [36,66].

However, there remains a lot of uncertainty as to the upper safelimit of vitamin A intake: the WHO advises against intakes over0.9 mg/d [7] among infants but without evidence from studiesshowing adverse effects, and the IOM gives an upper-limit of0.6 mg/d for children under 3 years of age [67]. Toxicity has beenobserved with daily intakes of 0.45 mg/kg for 6 months [68] whichwould translate to around 4 mg/d for a normal 1 year old. Theselimits are for healthy children with normal stores but consideringthat malnourished children seem to start with deficiencies, highersafety cut-offs would probably apply. The vitamin A content of RUTFis about 0.2 mg/100 kcal [3] and following the current dosagerecommendations the daily intake would equal 0.4 mg/kg or 3 mgfor an average 1-year-old child with SAM. It thus seems unlikelythat the current dose of RUTF would result in excessive intakes.Unfortunately serum RBP is not a good marker of excessive vitaminA stores but mainly designed to detect deficiency and thus we couldnot assess risk of excessive vitamin A among the studied children[65]. Studies aiming at providing evidence on the vitamin A statusof children with SAM are advised to use more appropriate methodssuch as stable isotope techniques to study the full range of vitaminA stores [65]. Looking into actual intake of RUTF and other foodsduring treatment would also be crucial in determining the potentialsources and actual quantity of vitamin A intake during treatment.

The strength of the current study is the high rate of success inobtaining biomarker data. This allows for a confident estimation of

vitamin A and iron status at admission to and recovery fromtreatment. We also had a sufficient sample size to apply adjustmentfor inflammation using internal regression coefficients recom-mended by the BRINDA study group [24e26].

Our study also has limitations. First, we only obtained data atdischarge from a third of non-recovered children with few datapoints from referrals or other potentially “worst off” patients. Thus,the discharge data probably overestimates the mean effect amongall treated children and underestimates the deficiencies atdischarge, representing a “best case” scenario. Second, we did notcollect data on the timing of the high-dose vitamin A supplemen-tation campaigns. Therefore, we could not account for the impact oftime since high-dose supplementation prior to admission.

In conclusion, reducing the RUTF dose does not seem to havean impact on the vitamin A and iron status of treated children.Only haemoglobin was slightly lower at recovery among childrentreated with the reduced dose. However, the vitamin A and ironstatus remained sub-optimal among children treated successfullyfor SAM with RUTF. Thus, there is a need to carefully reconsidermicronutrient fortification levels in RUTF or test other strategiesaiming at improving the micronutrient status of children treatedfor SAM.

Funding sources

This trial was funded by Action Against Hunger France, Euro-pean Commission's Civil Protection and Humanitarian aid Opera-tions, Children's Investment Fund Foundation, EuropeanCommission's Civil Protection and Humanitarian aid OperationsEnhanced Response Capacity and Humanitarian Innovation Fund, aprogramme managed by Enhancing Learning and Research forHumanitarian Assistance. The funders had no role in study design,data collection and analysis, decision to publish, or preparation ofthe manuscript.

Data availability

The dataset used and analysed during the current study isavailable from the Zenodo data repository: https://zenodo.org/record/3582441.

Conflict of interest

HF has received research grants from ARLA Food for HealthCentre, Danish Dairy Research Foundation and also has researchcollaboration with Nutriset. Other authors declare no conflicts ofinterest.

S.T. Kangas et al. / Clinical Nutrition 39 (2020) 3512e35193518

CRediT authorship contribution statement

Suvi T. Kangas: Conceptualization, Methodology, Formal anal-ysis, Investigation, Data curation, Writing – original draft, Writing -review & editing, Visualization, Project administration, Fundingacquisition. C�ecile Salp�eteur: Conceptualization, Writing – review& editing, Project administration, Funding acquisition. VictorNiki�ema: Data curation, Writing – review & editing, Projectadministration. Leisel Talley: Conceptualization, Writing – review& editing. Andr�e Briend: Conceptualization, Methodology, Vali-dation, Writing – review & editing, Supervision. Christian Ritz:Methodology, Formal analysis, Writing – review & editing. HenrikFriis: Conceptualization, Methodology, Validation, Investigation,Writing – review & editing, Supervision. Pernille Kaestel:Conceptualization, Methodology, Validation, Formal analysis,Investigation, Writing – review & editing, Supervision.

Acknowledgements

We thank the research teams for their everyday efforts inimplementing the trial and the study participants and caregiversfor participating in the trial.

Appendix A. Supplementary data

Supplementary data to this article can be found online athttps://doi.org/10.1016/j.clnu.2020.03.016.

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