Early growth faltering in healthy term infants predicts longitudinal growth.

Background: Early growth monitoring may not identify infants at-risk for later growth faltering because it is difficult for the provider to recognize how large of a negative shift might be problematic.

Aim: The aim of this study was to determine whether a slowing in early weight-for-age could be used to identify children at increased risk of later growth faltering.

Methods: Longitudinal data for infants aged birth to two years were analyzed for 1978 healthy, term infants born between 1999-2001. Logistic regression techniques were used to determine whether a negative change in weight-for-age, across well-child visit intervals, can identify infants at risk for growth faltering.

Results: The period prevalence of underweight was 24%. The odds ratio (OR) for infants with a negative shift in z-scores>or=-0.85 between four and six months was 2.4 (95% CI 1.5, 3.9) compared to those without this shift, holding birth weight constant. Sensitivity analyses revealed that the model was significant when either the 2000 CDC growth charts (p<0.0001) or the 2006 WHO growth charts (p<0.0001) were used as the reference, although the prevalence of underweight was lower (14.7%) when the 2006 WHO growth charts were the reference.

Conclusion: The findings support the hypothesis that a downward shift in weight-for-age of this magnitude during early infancy when well-child visits are most frequent can be used to identify children at risk of later poor growth.