Poster Topical Area: Global Nutrition
Location: Hall D
Poster Board Number: 593
Objective: Interest in promoting adolescent health, nutrition and growth is increasing, especially in rural South Asia where stunting is a public health burden from infancy through adulthood. However, little is known about usual adolescent growth in such environs to frame goals and guide interventions. In rural northwest Bangladesh, we assessed status and annual velocities in height (Ht, cm), weight (Wt, kg), and body mass index (BMI, kg/m2) in a cohort of girls and boys 9-14 y of age.
Methods: Ht and Wt were assessed in each child’s birth month and ~1 year later among children of mothers who participated in an antenatal vitamin A or β-carotene supplement trial from 2001-7 (West et al JAMA 2017). Of n=35,072 eligible participants, n=27,876 (n=14,001 girls, n=13,865 boys 9-14 y at first visit) completed interviews and anthropometry twice. Z-scores for Ht-for-age (HAZ) and BMI-for-age (BMIZ) were calculated against the WHO growth reference; annualized velocities were calculated by the difference in measures, accounting for exact number of intervening days.
Results: In girls, Ht increased from 127.3±6.1 to 148.1±6.0 cm between 9 and 14 y, corresponding to a mean decline in HAZ of -1.57±0.94 to -1.69±0.85, while Wt increased from 23.1±3.9 to 38.6±6.6 kg and BMI from 14.2±1.6 to 17.5±2.4 kg/m2, reflecting a mean gain in BMIZ from -1.50±0.99 to -1.02±1.08. In boys, Ht increased from 127.3±5.7 to 149.6±8.4 cm, reflecting a larger decline in HAZ, from -1.48±0.88 to -1.78±1.08, while Wt rose from 23.6±3.5 to 36.9±7.3 kg and BMI from 14.5±1.4 to 16.4±2.0 kg/m2, with a decline in BMIZ from -1.37±1.0 at 9 y to -1.55±1.13. Ht velocity (cm/y) ranged from 1.9±1.7 to 6.4±2.1 cm/y in girls and 4.8±1.6 to 7.2±2.6 cm/y in boys, peaking at 10-11 y in girls and 13-14 y in boys. By 14-15 y, height velocity fell to lowest values in girls but remained 6.4±2.9 cm/y in boys. Weight gain ranged from 2.8±2.4 to 4.7±2.2 kg/y (at 11-12 y) in girls and 2.6±1.5 to 5.4±2.6 kg/y (at 14-15 y) in boys.
Conclusions: Ht status fell behind international norms for girls and boys from age 9-14 y, while BMI increased with age relative to norms in girls only. In girls, pre- or early adolescent interventions taking advantage of greatest Ht velocity might impact linear growth most, while body mass changes in both sexes remain to be understood.
Funding Source: Bill and Melinda Gates Foundation, GH614 and OPP1141435
Center for Human Nutrition, Department of International Health, The Johns Hopkins Bloomberg School of Public Health