The Double Burden of Malnutrition: A Systematic Review of Operational Definitions

Abstract

Background: Despite increasing research on the double burden of malnutrition (DBM; i.e., coexisting over- and undernutrition), there is no global consensus on DBM definitions.

Objectives: To identify published operational DBM definitions, measure their frequency of use, and discuss implications for future assessment.

Methods: Following a structured search of peer-reviewed articles with terms describing "overnutrition" [e.g., overweight/obesity (OW/OB)] and "undernutrition" (e.g., stunting, micronutrient deficiency), we screened 1920 abstracts, reviewed 500 full texts, and extracted 623 operational definitions from 239 eligible articles.

Results: We organized three identified DBM dimensions (level of assessment, target population, and forms of malnutrition) into a framework for building operational DBM definitions. Frequently occurring definitions included coexisting: 1) OW/OB and thinness, wasting, or underweight (n = 289 occurrences); 2) OW/OB and stunting (n = 161); 3) OW/OB and anemia (n = 74); and 4) OW/OB and micronutrient deficiency (n = 73).

Conclusions: Existing DBM definitions vary widely. Putting structure to possible definitions may facilitate selection of fit-for-purpose indicators to meet public health priorities.

Keywords: anemia; assessment; double burden; literature review; malnutrition; micronutrient deficiency; noncommunicable disease; obesity; stunting.

FIGURE 1

Flow of identification and eligibility assessment of articles for a systematic review of operational definitions of the double burden of malnutrition (DBM).

FIGURE 2

Articles published by year (n = 239) included in the systematic review of operational definitions of the double burden of malnutrition. *Data for 2017 include articles published up to July 11, 2017.

FIGURE 3

Major dimensions and research settings of the double burden of malnutrition (DBM) reported in 239 articles assessing DBM¹. ¹Many articles included multiple definitions of DBM; circle diameter is proportional to the number of articles in which the DBM characteristic was observed. ²Forms of malnutrition, level of assessment, and target population subgroups were classified per the original article's definition, indicator, and/or cutoff value (e.g., overweight/obesity was classified by the specified BMI range, and anemia was classified by the specified hemoglobin concentration). ³“Other” forms of malnutrition included: OW/OB paired with stunting and/or wasting; OW/OB paired with “chronic energy deficiency”; low HDL cholesterol paired with underweight; metabolic syndrome (MetS) paired with anemia; cardiometabolic risk factors (CMRFs; i.e., dyslipidemia, hyperglycemia, hypertension, abdominal obesity, and/or OW/OB) paired with underweight or micronutrient deficiencies; CMRFs or MetS paired with anemia, iron depletion, or vitamin A deficiency; macrosomia paired with low birth weight; OW/OB paired with low upper-arm circumference or low triceps skinfold measurements; and OW/OB paired with food insecurity. ⁴World Bank classifications (27). DBM; double burden of malnutrition; MN, micronutrient; OW/OB, overweight/obesity; PSC, preschool age children; TWU, thinness/wasting/underweight; WRA, women of reproductive age.

FIGURE 4

Framework for building operational definitions of the double burden of malnutrition (DBM) based on definitions observed in published literature. The framework for building operational definitions of the DBM can be used by analysts, program planners, and policymakers to determine the specific operational definition of DBM that meets their objective(s). The 3 dimensions of the operational definition (level of assessment, target population, and forms of malnutrition to assess) should be chosen with consideration of the country context and public health priorities, and include the purposeful selection of indicators fit to the purpose of the objective(s). ¹Population-level assessment refers to comparisons of national, regional, and subregional populations or smaller populations, such as a population of students within a school or a population of adult women within a community. Household-level assessment refers to comparisons among or across households of all or some specified household members. Dyad-level assessment refers to comparisons among or across mother-child pairs or caregiver-child pairs. Individual-level assessment refers to comparisons of different forms of malnutrition occurring within a single individual. ²Assessment of the target population can include ≥1 age groups. ³Widely used definitions of DBM assess the coexistence of 1 form of “overnutrition” and 1 form of “undernutrition.” This framework can be expanded to assess multiple forms of malnutrition, for example, when assessing a triple burden of malnutrition. Additional forms of “overnutrition” identified in our review included macrosomia. Additional forms of “undernutrition” identified in our review included chronic energy deficiency, low birth weight, low upper-arm circumference, low triceps skinfold measurement, and food insecurity.