High-Frequency Repeated Measures of Over 5,000 Infants Aged 6–27 Months Reveals Pattern of Growth Faltering in Rural Burkina Faso

Abstract

\n \n \n Linear growth faltering, failure to achieve one s potential for length or height at each age, is associated with increased risk of mortality and morbidity. Understanding the age-related patterns of growth faltering can inform timing of interventions and policies for prevention; however current knowledge is limited by cross-sectional data. We examine the longitudinal characterization of the timing of growth faltering among young children.\n \n \n \n Using longitudinal anthropometric data originally collected as part of a food-aid cost-effectiveness trial, we investigated individual growth curves of 5,039 children aged 6–27 months in Burkina Faso (108,580 total measurements) to determine whether growth faltering occurs through intermittent episodes of slower growth, or continuously slow growth. We visualized individual growth curves and used two-stage regressions to evaluate growth curve smoothness at\n different levels of attained length. To do this, we first obtained model fit and diagnostic parameters from individual regressions of each child s length on their age. Parameters extracted included R2, as a metric of curve smoothness, initial length at 6 months, and average velocity. We then regressed these parameters on individual-level attained length at study end.\n \n \n \n Growth faltering manifests as both continuously lower growth velocity throughout the observation period and greater heterogeneity in growth velocity amplitude. Children with lower attained length start smaller (Quintile 1 of attained length-63.1\xa0cm initial length; Quintile 5-68.4\xa0cm) and stay on their initial trajectories, continuously growing slower than their taller counterparts. In addition, a 0.01 increase in the R2 (smoothness) from regression of a child s length on their age is associated with a 3.10\xa0cm increase in attained length (95% CI: 2.80, 3.41), showing that smoother growth is also associated with higher attained length.\n \n \n \n Children who experience the most extreme growth faltering are likely to be less resilient to systematic growth-limiting conditions as well as episodic insults to their growth. Future research should investigate ways of improving environmental conditions to support growth.\n \n \n \n Financial support provided by the Food Aid Quality Review project, funded by the United States Agency for International Development.\n