Abstract
Human fetal development has been associated with brain health at later stages. It is unknown whether growth in utero, as indexed by birth weight (BW), relates consistently to lifespan brain characteristics and changes, and to what extent these influences are of a genetic or environmental nature. Here we show remarkably stable and life-long positive associations between BW and cortical surface area and volume across and within developmental, aging and lifespan longitudinal samples (N = 5794, 4-82 years of age, w/ 386 monozygotic twins, followed for up to 8.3 years w/12,088 brain MRIs). In contrast, no consistent effect of BW on brain changes was observed. Partly environmental effects were indicated by analysis of twin BW discordance. In conclusion, the influence of prenatal growth on cortical topography is stable and reliable through the lifespan. This early life factor appears to influence the brain by association of brain reserve, rather than brain maintenance. Thus, fetal influences appear omnipresent in the spacetime of the human brain throughout the human lifespan. Optimizing fetal growth may increase brain reserve for life, also in aging.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
In response to questions raised by reviewers, we have: 1) Conducted several additional analyses (e.g. the revised ms now includes both across- and within-sample replicability analyses of the birth weight effects on cortical change, and we have we have rerun the main models in an ROI-based fashion using ans not using spline models to fit age.) 2) Revised the manuscript to include clarifications of methods used, additional results (from additional analyses as mentioned above) and additional discussion of interpretations and limitations. This includes a discussion of possible mechanisms underlying the association between birth weight and cortical characteristics, and acknowledgement that data regarding cognitive functional relevance through the lifespan are not analyzed here.
https://github.com/LCBC-UiO/paper-birthweight-brainchange-2022
Abbreviations
- BW
- birth weight;
- MRI
- Magnetic Resonance Imaging
