The influence of growth on development outcome in extremely low birthweight infants at 2 years of age

Objective: To determine if weight <3rd and <10th centile at 2 years in extr emely low birthweight (ELBW) infants is associated with problems of develop ment and motor skills, and whether this association is explained by perinat al risk status. Methodology: One hundred and ninety-eight of 226 (88%) surviving ELBW infan ts born between January 1987 and December 1992 were assessed at 2 years cor rected age. Children were classified as being at low perinatal risk (n = 12 8) or high perinatal risk (n = 70) for adverse developmental outcome based on perinatal risk factors. Weight at 2 years was classified as <3rd, 3rd-9t h or greater than or equal to 10th centile for age and gender. Development was assessed using the Griffiths Mental Development Scales and motor skills using the Neurosensory Motor Developmental Assessment (NSMDA). Results: For the total study group weight centile was strongly related to G eneral Quotient (GQ) and motor abilities, For children <3rd percentile (n = 48) mean (GQ) was 90.4 (SD, 15.9), for children between the 3rd-9th percen tile (n = 49) 91.5 (SD, 17.9), and for children greater than or equal to 10 th percentile (n = 99) mean GQ was 99.8 (SD, 8.6). The association with mea n GQ and NSMDA category occurred for the high-risk subgroup and became non- significant in the low-risk subgroup if neurologically abnormal children we re excluded. Other perinatal risk factors, exposure to breast milk, level o f maternal education, marital status and history of feeding problems or inf ections over the 2 years did not confound this association. Conclusion: Low weight percentile at 2 years was related to adverse develop mental outcome in ELBW infants at high perinatal risk or with neurological impairment, though minimal association was present for neurologically norma l infants at low perinatal risk.