Early life exposure to economic shocks and association with childhood malnutrition: a pooled analysis of 230 nationwide surveys from 68 low-income and middle-income countries.

BACKGROUND

The relationship between economic growth and nutrition is not yet fully understood in the context of the new nutrition reality where most low-income and middle-income countries (LMICs) face an increasing double burden of malnutrition. We aimed to investigate the association between early life exposure to economic shocks and multiple forms of childhood malnutrition in LMICs.

METHODS

We pooled cross-sectional data on children younger than 5 years from the Demographic and Health Surveys from 1990 to 2022 and longitudinal income data from the World Inequality Database. An economic shock was defined as any negative income growth and was tested at intensity levels of less than -1%, -5%, and -10%. Malnutrition outcomes variables comprised stunting, wasting, overweight, obesity, concurrent wasting and stunting (WaSt), and double burden of malnutrition (child is both stunted and overweight). Adjusted associations of economic shocks, at different critical windows (year of the interview, birth, first 1000 days of life), with malnutrition outcomes were estimated by multivariable Poisson regression models with robust errors. The associations were interpreted using prevalence ratios (PRs) and 95% CIs.

FINDINGS

A total of 1 643 898 children across 230 surveys in 68 LMICs were included in this study. Negative income shocks in the year of interview were associated with a 5·4% (PR 1·054 [95% CI 1·029-1·080]) increase in the prevalence of wasting and a 12·7% (1·127 [1·079-1·176]) increase in severe wasting. A dose-response association according to the intensity levels of income shock in the year of birth was found for stunting (-1%: PR 1·019 [95% CI 1·011-1·027]; -5%: 1·033 [1·025-1·042]; and -10%: 1·061 [1·051-1·072]) and severe stunting (-1%: 1·041 [1·026-1·055]; -5%: 1·059 [1·044-1·074]; and -10%: 1·099 [1·081-1·118]). In children aged 2-4 years, income shocks during the first 1000 days of life strongly increased the prevalence of double burden of malnutrition by 30·3% (PR 1·303 [95% CI 1·221-1·391]), obesity by 14·3% (1·143 [1·046-1·249]), and overweight by 13·8% (1·138 [1·090-1·188]). We also found a strong dose-response association between the intensity of income shock during the first 1000 days and double burden of malnutrition (-1%: PR 1·216 [95% CI 1·141-1·295]; -5%: 1·299 [1·192-1·416]; -10%: 1·350 [1·185-1·537]).

INTERPRETATION

Exposure to negative income shocks can significantly increase the risk of various forms of malnutrition during childhood, with critical windows of vulnerability that vary based on the timing of economic instability and the specific type of malnutrition. Policymakers and public health practitioners must recognise these critical periods and develop targeted interventions to safeguard maternal and child nutrition, particularly during times of economic crises.

FUNDING

Ministry of Science, Innovation and Universities of Spain; Spanish State Research Agency; Generalitat de Catalunya through the CERCA Program; and Wellcome Trust.