Influences on catch-up growth using relative versus absolute metrics: evidence from the MAL-ED cohort study

BackgroundPoor growth in early childhood has been considered irreversible after 2-3years of age and has been associated with morbidity and mortality over the short-term and with poor economic and cognitive outcomes over the long-term. The MAL-ED cohort study was performed in eight low-income settings with the goal of evaluating relationships between the child's environment and experience (dietary, illness, and pathogen exposure, among others) and their growth and development. The goal of this analysis is to determine whether there are differences in the factors associated with growth from 24 to 60months using two different metrics.MethodsAcross six MAL-ED sites, 942 children had anthropometry data at 24 and 60months, as well as information about socioeconomic status, maternal height, gut permeability (lactulose-mannitol z-score (LMZ)), dietary intake from 9 to 24months, and micronutrient status. Anthropometric changes were in height- or weight-for-age z-score (HAZ, WAZ), their absolute difference from the growth standard median (HAD (cm), WAD (kg)), as well as recovery from stunting/underweight. Outcomes were modeled using multivariate regression.ResultsAt 24months, almost half of the cohort was stunted (45%) and 21% were underweight. Among those who were stunted at 24months (n=426), 185 (43%) were no longer stunted at 60months. Most children increased their HAZ from 24 to 60months (81%), whereas fewer (33%) had positive changes in their HAD. Linear regression models indicate that girls improved less than boys from 24 to 60months (HAZ: -0.21 (95% CI -0.27, -0.15); HAD: -0.75 (-1.07, -0.43)). Greater intestinal permeability (higher LMZ) at 0-24months was associated with lower relative and absolute changes from 24 to 60months (HAZ: -0.10 (-0.16, -0.04); HAD: -0.47 (-0.73, -0.21)). Maternal height (per 10cm) was positively associated with changes (HAZ: 0.09 (0.03, 0.15); HAD: 0.45 (0.15, 0.75)). Similar relationships were identified for changes in WAZ and WAD.ConclusionsThe study children demonstrated improved growth from 24 to 60months of age, but only a subset had positive changes in HAD and WAD. The same environmental factors were associated with growth from 24 to 60months regardless of metric used (change in HAZ or HAD, or WAZ and WAD).

Automated summary

The study found that most children showed improved growth from 24 to 60 months, but only a subset had positive changes in HAD and WAD. Growth from 24 to 60 months was associated with the same environmental factors regardless of the metric used.