Aging and Alzheimer's disease: lessons from the Nun Study.
Level 3 - non-randomized controlled study
Prospective longitudinal cohort study with clinicopathological correlation
PubMed 9127971 · doi:10.1093/geront/37.2.150
What was done
The authors examined the relationship between cognitive performance and postmortem neuropathology across 678 participants in the Nun Study, highlighting the index case of Sister Mary who was tracked until death at age 101.
What was found
The abstract reports no aggregate quantitative statistics or effect estimates. It reports that Sister Mary maintained high cognitive test scores prior to death at age 101 despite autopsy findings showing abundant classic Alzheimer's lesions, including neurofibrillary tangles and senile plaques.
Why it matters
The findings provide early clinical evidence for cognitive reserve, demonstrating that abundant pathological hallmarks of Alzheimer's disease do not inevitably produce clinical dementia.
Limits
The abstract provides no numerical data, diagnostic thresholds, or quantitative neuropathology metrics. The cohort is restricted to Roman Catholic sisters with homogeneous lifestyles, environments, and reproductive histories, limiting generalizability to the general public.
Cited by
- supports In the Nun Study, some participants had hallmark Alzheimer's disease pathology including amyloid plaques and neurofibrillary tangles upon post-mortem examination, but remained cognitively high functioning during life.