Brain age relates to early life factors but not to accelerated brain aging
D. Vidal-Piñeiro, Y. Wang, SK. Krogsrud, IK. Amlien, WFC. Baaré, D. Bartrés-Faz, L. Bertram, A.M. Brandmaier Dr, CA. Drevon, S. Düzel, KP. Ebmeier, RN Henson, C. Junque, RA Kievit, S. Kühn, E. Leonardsen, U. Lindenberger, KS. Madsen, F. Magnussen, AM. Mowinckel, L. Nyberg, JM. Roe, B. Segura, Ø. Sørensen, S. Suri, E. Zsoldos, the Australian Imaging Biomarkers and Lifestyle flagship study of ageing, KB. Walhovd, AM. Fjell. Preprint, 2021.
Brain age is an influential index for quantifying brain health, assumed partially to reflect the rate of brain aging. We explicitly tested this assumption in two large datasets and found no association between cross-sectional brain age and steeper brain decline. Rather, brain age in adulthood was associated with early-life influences indexed by birth weight and polygenic scores. The results call for nuanced interpretations of cross-sectional indices of the aging brain.