Being born small for gestational age reduces white matter integrity in adulthood: a prospective cohort study.

BACKGROUND: Being born small for gestational age (SGA) (birth weight <10th percentile) is connected to decreased white matter (WM) integrity in newborns and increased prevalence of psychiatric symptoms in adulthood. The aims of this study were to investigate whether being born SGA at term affects WM integrity in young adulthood and to explore possible relationships between fractional anisotropy (FA) and pre- and perinatal factors and cognitive and psychiatric outcomes in adulthood in SGA and controls. METHODS: Diffusion tensor imaging and tract-based spatial statistics were conducted to test for voxelwise differences in FA in SGAs (n = 46) and controls (n = 57) at 18-22 y. RESULTS: As compared with controls SGAs had reduced FA in ventral association tracts and internal/external capsules. In the SGAs, no relationship was found between FA and intrauterine head growth in the third trimester, although total intelligence quotient was negatively correlated to FA. In controls, a positive correlation was found between FA and brain growth in the third trimester and maternal smoking. No relationship was found between FA and psychiatric measures in SGAs or controls. CONCLUSION: These results demonstrate that being born SGA leads to reduced WM integrity in adulthood, and suggest that different factors modulate the development of WM in SGA and control groups.