DIET & NUTRITION 
PATIENT EDUCATION 
OBESITY/WEIGHT MANAGEMENT 
EXERCISE/TRAINING 
LEGAL MATTERS 
GUIDELINES/RECOMMENDATIONS ℹ️ Observational Association Only Evidence
A Mayo Clinic Study of Aging analysis of 2,082 participants (median age 71, 87% cognitively unimpaired) identified statistically significant breakpoints in plasma, imaging, and cognitive biomarkers, clustering near late midlife.
Clinical Considerations
- GFAP inflected at 68.1 years, NfL at 70.7 years, and p-tau181 at 67.2 years, with steeper trajectories after each breakpoint.
- Amyloid PET shifted earlier at 62.3 years, while plasma Aβ42/40 declined from a much earlier inflection at 48.5 years.
- Global cognition demonstrated a slope change at 59.8 years; tau PET showed no significant breakpoint in this cohort.
- In a mass spectrometry subsample (n=462), p-tau217 and p-tau181 both inflected near 72.6 years, with steeper later-life increases.
Practice Applications
- Interpret plasma AD biomarkers against age-stratified trajectories, not single thresholds.
- Recognize that breakpoints are population-level signals, not individual diagnostic cutoffs.
- Consider the cognitively unimpaired skew when generalizing to symptomatic patients.
- Monitor for evolving guidance as biomarker-based screening windows matur
