title: Subcutaneous fat accumulation in early infancy is more strongly associated with motor development and delay than muscle growth.
abstract: OBJECTIVE
  Physical growth in neurologically healthy preterm infants affects motor development. This study investigated the separate relationships between muscle and fat in infancy and later motor development and physical growth.
  
  
  METHODS
  Muscle thickness and subcutaneous fat thickness of the anterior thigh were measured using ultrasound images obtained from neurologically healthy preterm infants at birth, 3, 6, 12 and 18 months' corrected age. We also obtained the Pediatric Evaluation of Disability Inventory and Alberta Infant Motor Scale scores at 18 months' corrected age to assess motor ability and motor delay.
  
  
  RESULTS
  Thirty preterm infants completed the study protocol. There was a significant positive correlation between motor ability and increments in subcutaneous fat thickness during the first 3 and 6 months' corrected age (r = 0.48 and 0.40, p < 0.05, respectively), but not between motor ability and muscle thickness growth in any of the periods. A secondary, logistic regression analysis showed that increments in subcutaneous fat thickness during the first 3 months were a protective factor for motor delay.
  
  
  CONCLUSIONS
  Subcutaneous fat accumulation in early infancy is more strongly associated with motor development and delay than muscle growth.
authors: Department of Pediatrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan; Research fellow of the Japan Society for the Promotion of Science, Tokyo, Japan.
authors: H
authors: H
authors: Kanazawa
authors: M
authors: M
authors: Kawai
authors: F
authors: F
authors: Niwa
authors: T
authors: T
authors: Hasegawa
authors: K
authors: K
authors: Iwanaga
authors: K
authors: K
authors: Ohata
authors: A
authors: A
authors: Tamaki
authors: T
authors: T
authors: Heike
mesh_terms: D000704:Analysis of Variance; D002657:Child Development; D005544:Forecasting; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D007564:Japan; D016015:Logistic Models; D009048:Motor Skills / Q000502:physiology*; D019957:Motor Skills Disorders; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000254:growth & development* / Q000502:physiology; D018709:Statistics, Nonparametric; D050151:Subcutaneous Fat / Q000000981:diagnostic imaging / Q000254:growth & development* / Q000502:physiology; D014463:Ultrasonography; D015430:Weight Gain
keywords: Motor development; Muscle; Physical growth; Preterm; Subcutaneous fat