A 1-year cohort of children born at term in Newcastle-upon-Tyne in 1987/8 was screened for
failure to thrive in infancy using a conditional longitudinal standard which identified those
whose weight gain was in the lowest 5%. A group of 136 cases and 136 controls (from the
same GP practice and living in a neighbourhood with the same deprivation index) was
followed up at 7–9 years of age, when 79% of cases and 87% of controls were successfully
studied. Cases at 7–9 were significantly shorter (mean 126.0 cm, SD 5.6) than controls (mean
130.7 cm, SD 5.9); adjusted for parental heights a difference of 4.4 cm (95% CI 2.92 to
5.90 cm) remained. They had smaller head circumferences (mean 51.9 cm, SD 1.8) than
controls (mean 52.8 cm, SD 1.7), were significantly lighter (medians 23.8 kg, IR 21.5 to 26.9
in cases, and 27.9 kg, IR 25.2 to 31.6 in controls) and had a lower body mass index (median
14.9, IR 14.1 to 16.0 in cases, and 16.3, IR 15.3 to 17.8 in controls). Despite these large
growth differences, no statistically significant differences in cognitive outcomes were found.
Mean IQ was 87.6 (SD 17.4) in cases and 90.6 (SD 17.1) in controls; after adjustment for
organic cause and mother's IQ the mean difference was 1.7 IQ points (95%CI −5.2 to 1.9).
There were no statistically significant differences in the reading, spelling, or reading
comprehension scores; the mean standardised reading score was 93.5 (SD 16.2) for cases and
94.5 (SD 15.6) for controls. These results show that when carefully defined by velocity-based
anthropometric criteria, nonorganic failure to thrive in infancy is followed by persisting
stunting and wasting, and a reduced head circumference, but is not associated with cognitive
or educational disadvantages at school age.