Non-Organic Failure to Thrive

Abstract

Source: Ramsay M, Gisel EG, McCusker J, et al. Infant sucking ability, non-organic failure to thrive, maternal characteristics, and feeding practices: a prospective cohort study. Dev Med Child Neurol. 2002;44:405–414.These investigators explored whether inefficient sucking, later feeding difficulties, and/or maternal depression contributed to non-organic failure to thrive (NFTT). Healthy term infants and their mothers were recruited from St. Mary’s Hospital in Montreal, Canada, within 24 hours of birth and were tested at 1 week of age to determine if inefficient sucking was associated with slow weight gain. Those with inefficient sucking comprised the index group (n=265), and an equal number of randomly selected infants with efficient sucking (sustained frequency, amplitude, and duration) comprised the matched control group (n=255). Both groups were retested in the home at 2, 6, 10, and 14 months of age with various combinations of the Edinburgh Postnatal Depression Scale completed by the mother, a feeding questionnaire administered by trained evaluators, an observation of infant feeding behavior, anthropometric measurements of the infant, and measurement of the infant’s suck. NFTT was defined as exhibiting 2 of the following: 1) weight loss across 2 major percentiles (n=32), 2) weight for length below 90th percentile of ideal weight (adjusted for parental height) (n=15), and 3) weight for age below 5th percentile (n=3), all in the absence of recognized organic disease. Eighteen infants were thus classified as NFTT. Inefficient sucking at 1 week did not predict later feeding difficulties, and postnatal growth was not influenced by early or concurrent maternal depression or maternal feeding practice.The data in this study did not allow an analysis of the possibility that these NFTT infants were simply adjusting their growth curve to a genetically preprogrammed lower one. The researchers were unable to demonstrate an association between early sucking efficiency and later feeding difficulties. This does not rule out a predominantly oral motor etiology for much of what is classed as NFTT; it simply demonstrates that a measure of sucking efficiency at 1 week is not sensitive to the later expression of feeding difficulties. Indeed, while 94% of infants with efficient sucking remained efficient at 2 months, only 50% of infants with inefficient sucking remained inefficient at 2 months. Perhaps this study’s failure to demonstrate any association between maternal depression and NFTT will help retire that tired presumption. The 2 etiologies for these growth patterns that would seem to be underestimated are: 1) subtle oral-motor difficulties1 and/or 2) the infants are simply following a familial growth curve. However the cookie crumbles, the infant’s failure to grow appropriately is often attributed to the mother. Perhaps this presumption should also be retired.