NEFL and Alzheimer disease: Nonetheless, some studies report differing trajectories—for example, recent studies have shown that women with amyloid-positive AD have slower cognitive decline than men despite exhibiting earlier hippocampal atrophy and a greater burden of white matter abnormalities (Inguanzo et al., 2025) and men have demonstrated steeper increases in plasma pTau181, pTau231, and NFL (Joynes et al., 2025), underscoring the complexity and heterogeneity of sex effects across cohorts and in vivo biomarkers.