Individual variations in “Brain age” relate to early life factors more than to longitudinal brain change
Vidal-Piñeiro D., Wang Y., Krogsrud SK., Amlien IK., Baaré WFC., Bartrés-Faz D., Bertram L., Brandmaier AM., Drevon CA., Düzel S., EBMEIER KP., Henson RN., Junque C., Kievit RA., Kühn S., Leonardsen E., Lindenberger U., Madsen KS., Magnussen F., Mowinckel AM., Nyberg L., Roe JM., Segura B., Sørensen Ø., SURI S., Westerhausen R., Zalesky E., ZSOLDOS E., Australian Imaging Biomarkers and Lifestyle flagship study of ageing None., Walhovd KB., Fjell AM.
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.