Abstract
OBJECTIVE: To examine how infant overweight and high subcutaneous fat relate to infant motor development. STUDY DESIGN: Participants were from the Infant Care, Feeding, and Risk of Obesity Project, a prospective, longitudinal study of low-income African-American mother-infant dyads assessed from 3 to 18 months of age (836 observations on 217 infants). Exposures were overweight (weight-for-length z-score>or=90th percentile of 2000 Centers for Disease Control/National Center for Health Statistics growth reference) and high subcutaneous fat (sum of 3 skinfold measurements>90th percentile of our sample). Motor development was assessed by using the Bayley Scales of Infant Development-II. Developmental delay was characterized as a standardized Psychomotor Development Index score<85. Longitudinal models estimated developmental outcomes as functions of time-varying overweight and subcutaneous fat, controlling for age and sex. Alternate models tested concurrent and lagged relationships (earlier weight or subcutaneous fat predicting current motor development). RESULTS: Motor delay was 1.80 times as likely in overweight infants compared with non-overweight infants (95% CI,1.09-2.97) and 2.32 times as likely in infants with high subcutaneous fat compared with infants with lower subcutaneous fat (95% CI, 1.26-4.29). High subcutaneous fat was also associated with delay in subsequent motor development (odds ratio, 2.27; 95% CI, 1.08-4.76). CONCLUSIONS: Pediatric overweight and high subcutaneous fat are associated with delayed infant motor development.