A Critical Evaluation of the Appetite Test for Children with Severe Acute Malnutrition

Abstract

Background: In children with severe acute malnutrition (SAM) the appetite test is used to risk-stratify for in-patient or outpatient care. The appetite test is recommended in national and international guidelines despite lack of evidence. We evaluated its ability to identify children at risk of a poor treatment outcome. Methods: We conducted a prospective observational study of children with SAM in 3 sites in Ethiopia. We did the appetite test and a simple standardised examination for medical complications, performed blood cultures, and analysed blood samples. The appetite test was done by research nurses independent of the routine staff, and the result did not affect decisions for hospitalisation, clinical care and treatment duration. Data were analysed using a mixed linear model for continuous outcomes and a mixed model logistic regression for binary outcomes. Findings: Appetite was tested in 298 of 343 enrolled children and only 56 (19%) passed. Counter-intuitively, children failing the appetite test had a 5·66 g/kg/day (95% CI 3·84; 7·48) higher weight gain during follow-up than children passing it, adjusted for type and duration of treatment, oedema, duration of follow-up, and age (p<0·0001). We found one or more medical complications in 179 (54%) of the patients. Those with complications had a 4·48 g/kg/day (95% CI 2·76, 6·19) lower weight gain than those without complications. Having medical complications but not the appetite test result was associated with blood markers of metabolic disturbances. Neither the appetite test nor medical complications were associated with bacteraemia (n=11), treatment failure (n=57) or mortality (n=17). Interpretation: Our findings question the rationale for using the appetite test and challenge its use to identify children who need in-patient care. We suggest that a simple assessment of medical complications alone would suffice for this purpose. Funding Statement: University of Copenhagen, Aase and Ejnar Danielsen Fond, Augustinus Foundation and Rigshospitalet. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: Jimma University Institutional Review Board (IRB) and the Ethiopian National Research Ethics Review Committee gave ethical approval and the Danish National Committee on Health Research Ethics gave consultative approval. Children were eligible after obtaining written informed consent from their caregivers, in their primary language.