Subthreshold early white-matter hyperintensity increase predicts accelerated hippocampal and whole-brain atrophy in anti-amyloid-β immunotherapy.

Twenty-two participants (74 ± 11 years; 14 women) were followed for 376 ± 146 days.

Significant volume changes occurred in all regions (p < 0.01).

Piecewise regression revealed an initial white matter hyperintensities surge that decelerated after 60 days (β=-0.19 [95%CI: -0.33, -0.042], p = 0.01), whereas gray matter regions showed linear volume decline.