Symmetrical and asymmetrical growth restriction in preterm-born children

OBJECTIVE: To determine how symmetric (proportionate; SGR) and asymmetric (disproportionate; AGR) growth restriction influence growth and development in preterms from birth to 4 years.

METHODS: This community-based cohort study of 810 children comprised 86 SGR, 61 AGR, and 663 non-growth restricted (NGR) preterms, born in 2002 and 2003. Symmetrical growth restriction was defined as a birth weight below the 16th percentile (-1 SD) compared with full-terms and a head circumference (HC) z score not exceeding the infant's birth weight z score by >1 SD. Asymmetric growth restriction was defined as a HC z score exceeding that for by >1 SD as a proxy of brain sparing. Developmental delay was assessed by the Ages and Stages Questionnaire at 4 years.

RESULTS: Longitudinal gains in weight and height were similar for SGR and AGR children and less compared with NGR children. At age 4, z scores for weight were -1.1 for SGR and -0.7 for AGR children vs -0.3 for NGR children. z scores for height were -0.8 and -0.5 vs. -0.2. HC gain were 2 cm more in SGR, but at 1 year, they were -0.2 vs. 0.2 (AGR) and 0.1 (NGR). Developmental delay increased with odds ratios of 2.5 (95% confidence interval 1.1-6.0) for SGR and 2.1 (95% confidence interval 0.7-5.9) for AGR.

CONCLUSIONS: Weight and height gains were similar for AGR and SGR children but poorer compared with NGR children. SGR children caught up on HC. Developmental delay was more likely in growth-restricted preterms independent of HC at birth.