Early growth velocities and weight gain plasticity improve linear growth in Peruvian infants

Short-term dynamics of linear growth among Peruvian infants in the first year of life in a population with linear growth faltering

OBJECTIVES

Infant growth is recognized to vary over the short term, with periods of greater and lesser linear growth velocity. Our objectives were to (1) examine the potential differences in overall growth profiles between children who experienced cumulative growth faltering in the first year of life consistent with that seen by many children living in poverty in low- and middle-income countries, versus children without growth faltering and (2) test whether biological factors were associated with the timing of magnitude of growth saltations.

METHODS

Thrice-weekly measurements of length were recorded for n = 61 Peruvian infants (28 boys and 33 girls) enrolled from birth to 1 year. A total of 6040 measurements were analyzed. We tested for the evidence of saltatory growth and used hurdle models to test whether the timing and magnitude of saltations varied between children with greater or lesser growth faltering.

RESULTS

There were no differences in the duration of stasis periods or magnitude of growth saltations between children who were stunted at 1 year old (N = 18) versus those who were not stunted (N = 43). Children who experienced greater declines in LAZ in the first year of life trended toward longer periods between saltations than those with less of a decline (14.5 days vs. 13.4 days, p = .0512). A 1-unit increase in mid upper arm circumference for age Z-score in the 21 days prior was associated with 35% greater odds of a saltation occurring (p < .001), and a 0.128 cm greater saltation (p < .001).

CONCLUSIONS

After characterizing infant growth into periods of saltation and stasis, our results suggest that increases in weight preceded increases in length.

US Evaluation of Bone Age in Rural Ecuadorian Children: Association with Anthropometry and Nutrition

Background Stunted growth and development is a serious global public health problem. A limited number of field measures exist that can be used to evaluate stunting and its underlying biologic mechanisms. Purpose To assess bone age using tablet-based US in young children living in a rural community in Ecuador, where stunting is prevalent, and to evaluate the associations between bone age, anthropometry, and diet. Materials and Methods From June through August 2017, tablet-based US was used to assess bone age in young children within their homes in rural Cotopaxi, Ecuador. Bone age z scores (BAZs) were assigned using the standards of Greulich and Pyle. Anthropometric data were collected using international protocols; z scores were generated from World Health Organization Child Growth Standards. Groups were compared using the Student t test. Univariate analyses and generalized linear regression modeling were applied to test the association between bone age and anthropometry, adjusting for covariates including age, sex, dietary intake, and morbidities. Results A total of 128 children (mean age, 33.9 months ± 1.8 [standard deviation]; 59 girls, 69 boys) were evaluated. Mean BAZ was -1.20 ± 1.16. Mean BAZ was lower in children with stunted growth (-1.42 ± 1.18) than in children without stunted growth (-0.98 ± 1.10, P = .04). In adjusted analysis, BAZ was associated with the following variables: height-for-age z score (β coefficient, 0.26; 95% confidence interval [CI]: 0.05, 0.46; P = .01), female sex (β coefficient, 0.51; 95% CI: 0.15, 0.88; P = .006), number of times eggs were consumed in the previous 24 hours (β coefficient, 0.22; 95% CI: 0.05, 0.38; P = .009), number of times savory or salty snacks were consumed in the previous 24 hours (β coefficient, 0.42; 95% CI: 0.15, 0.68; P = .002), and ownership of pig livestock, which was a binary variable (β coefficient, -0.46; 95% CI: -0.82, -0.09; P = .01). Conclusion Bone age determined using tablet-based US was lower in children who had stunted growth and was associated with diet in a cohort of children living in rural Ecuador. © RSNA, 2020 See also the editorial by Dillman and Ayyala in this issue.

Predicting Undernutrition at Age 2 Years with Early Attained Weight and Length Compared with Weight and Length Velocity

OBJECTIVE

To estimate the abilities of weight and length velocities vs attained growth measures to predict stunting, wasting, and underweight at age 2 years.

STUDY DESIGN

We analyzed data from a community-based cohort study (The Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development study [MAL-ED] study) in Bhaktapur, Nepal. A total of 240 randomly selected children were enrolled at birth and followed up monthly up to age 24 months. Linear and logistic regression models were used to predict malnutrition at 2 years of age with growth velocity z scores at 0-3, 0-6, 3-6, 6-9, 6-12, and 9-12 months (using the World Health Organization Growth Standards) or attained growth at 0, 3, 6, and 12 months as predictors.

RESULTS

At age 2 years, 4% of the children were wasted, 13% underweight, and 21% stunted. Children who were malnourished at age 2 years had lower mean growth z scores already at birth and throughout the study period. Anthropometric indicators in infancy were significant predictors for growth at the age of 2 years during most periods and at most ages in infancy. Weight-for-age z score, length-for-age z score, and weight-for-length z score at age 12 months had excellent areas under the curve (91-95) to predict the value of the same indicator at age 24 months. Maximum area under the curve values for weight and length velocity were somewhat lower (70-84).

CONCLUSIONS

Growth measured at one time point in infancy was better correlated with undernutrition at age 2 years than growth velocity.