dc.description.abstract | Background and Purposes: Preterm infants with very low birth weight (VLBW, birth weight < 1,500g) are at risk of motor disorders that require early assessment and intervention. Previous studies on early motor development in preterm infants were mostly based on single time point and have relied on estimation of mean performance that the variation within group over age and the influencing factors were rarely explored. Therefore, the purposes of this study were to examine the developmental trajectories of gross motor function in VLBW preterm infants during the first year of life, to investigate the influencing factors for the motor trajectories, and to investigate the prediction of later neurodevelopmental outcome by early motor trajectories. Methods: A total of 342 VLBW preterm infants were prospectively assessed for their motor function by the Alberta Infant Motor Scales (AIMS) at 4, 6, 9 and 12 months of corrected age, and were examined for the cognitive and motor function by the Bayley Scales of Infant and Toddler Development-2nd edition (BSID-II) at two years of corrected age. Perinatal and socio-environmental factors were also collected. Results: VLBW preterm infants showed three distinct motor developmental trajectories during the first year of life: stably normal (55%), deteriorating (32%), and persistently delayed (13%). The deteriorating pattern was significantly associated with low birth body weight (odds ratio (OR) [95% confidence interval (CI)] = 1.1 [1.0-1.1]), male gender (OR [95% CI]= 2.4 [1.4-3.8]), and moderate/severe bronchopulmonary dysplasia (OR [95% CI]= 2.9 [1.7-5.0]); whereas the persistently delayed pattern was significantly associated with low birth body weight (OR [95% CI]= 1.1 [1.0-1.1]), moderate/severe bronchopulmonary dysplasia (OR [95% CI] = 5.1 [2.3-11.4]), stage III/IV retinopathy of prematurity (OR [95% CI] = 7.2 [2.6-19.9]), and major brain damage (OR [95% CI] = 51.5 [6.3-423.4]) (all p < 0.05). Furthermore, the deteriorating pattern was predictive of motor delay (borderline delay, OR [95% CI] = 3.2 [1.8-5.7]; significant delay, OR [95% CI] = 20.6 [4.6-92.0]) and mental delay (borderline delay, OR [95% CI] = 2.4 [1.4-4.3]; significant delay, OR [95% CI] = 6.6 [2.1-20.8]) at two years of corrected age; whereas the persistently delayed pattern was predictive of motor delay (borderline delay, OR [95% CI] = 8.0 [3.3-19.4]; significant delay, OR [95% CI] = 83.4 [16.1-432.7]) and mental delay (borderline delay, OR [95% CI] = 7.6 [3.0-18.9]; significant delay, OR [95% CI] = 28.5 [7.8-103.5]) at two years of corrected age (all p < 0.05). Conclusion: VLBW preterm infants manifested various motor trajectories throughout the first year of life that were mainly related to perinatal factors and were predictive of later motor and mental outcome. The results provided insightful information for early detection and intervention of motor disorders in VLBW preterm infants. | en |