Global brain volume and N-acetyl-aspartate decline over seven decades of normal aging.

Journal Article (Journal Article)

We characterize the whole-brain N-acetyl-aspartate (WBNAA) and brain tissue fractions across the adult lifespan and test the hypothesis that, despite age-related atrophy, neuronal integrity (reflected by WBNAA) is preserved in normal aging. Two-hundred-and-seven participants: 133 cognitively intact older adults (73.6 ± 7.4 mean ± standard deviation, range: 60-90 year old) and 84 young (37.9 ± 11, range: 21-59 year old) were scanned with proton magnetic resonance spectroscopy and T1-weighted MRI. Their WBNAA, fractional brain parenchyma, and gray and white matter volumes (fBPV, fGM, and fWM) were compared and modeled as functions of age and sex. Compared with young, older-adults' WBNAA was lower by ~35%, and fBPV, fGM and fWM were lower by ~10%. Linear regressions found 0.5%/year WBNAA and 0.2%/year fBPV and fGM declines, whereas fWM rose to age ~40 years, and declined thereafter. fBPV and fGM were 1.8% and 4% higher in women, with no sex decline rates difference. We conclude that contrary to our hypothesis, atrophy was accompanied by WBNAA decline. Across the entire age range, women's brains showed less atrophy than men's. Formulas to estimate WBNAA and brain tissue fractions in healthy adults are provided to help differentiate normal from abnormal aging.

Full Text

Duke Authors

Cited Authors

  • Kirov, II; Sollberger, M; Davitz, MS; Glodzik, L; Soher, BJ; Babb, JS; Monsch, AU; Gass, A; Gonen, O

Published Date

  • February 2021

Published In

Volume / Issue

  • 98 /

Start / End Page

  • 42 - 51

PubMed ID

  • 33232854

Pubmed Central ID

  • PMC8215584

Electronic International Standard Serial Number (EISSN)

  • 1558-1497

Digital Object Identifier (DOI)

  • 10.1016/j.neurobiolaging.2020.10.024


  • eng

Conference Location

  • United States