This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
Abstract
Objective To test the hypothesis that higher level of cognitive activity predicts older age at dementia onset in Alzheimer disease (AD) dementia.
Methods As part of a longitudinal cohort study, 1,903 older persons without dementia at enrollment reported their frequency of participation in cognitively stimulating activities. They had annual clinical evaluations to diagnose dementia and AD, and the deceased underwent neuropathologic examination. In analyses, we assessed the relation of baseline cognitive activity to age at diagnosis of incident AD dementia and to postmortem markers of AD and other dementias.
Results During a mean of 6.8 years of follow-up, 457 individuals were diagnosed with incident AD at a mean age of 88.6 (SD 6.4, range 64.1–106.5) years. In an extended accelerated failure time model, higher level of baseline cognitive activity (mean 3.2, SD 0.7) was associated with older age at AD dementia onset (estimate 0.026; 95% confidence interval 0.013–0.039). Low cognitive activity (score 2.1, 10th percentile) was associated with a mean onset age of 88.6 years compared to a mean onset age of 93.6 years associated with high cognitive activity (score 4.0, 90th percentile). Results were comparable in subsequent analyses that adjusted for potentially confounding factors. In 695 participants who died and underwent a neuropathologic examination, cognitive activity was unrelated to postmortem markers of AD and other dementias.
Conclusion A cognitively active lifestyle in old age may delay the onset of dementia in AD by as much as 5 years.
Glossary
- AD=
- Alzheimer disease;
- CI=
- confidence interval;
- MAP=
- Memory and Aging Project;
- NIA=
- National Institute on Aging;
- NINCDS/ADRDA=
- National Institute of Neurologic and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association;
- TDP-43=
- transactive response DNA-binding protein 43
Footnotes
Go to Neurology.org/N for full disclosures. Funding information and disclosures deemed relevant by the authors, if any, are provided at the end of the article.
- Received January 28, 2021.
- Accepted in final form May 27, 2021.
- © 2021 American Academy of Neurology
AAN Members
We have changed the login procedure to improve access between AAN.com and the Neurology journals. If you are experiencing issues, please log out of AAN.com and clear history and cookies. (For instructions by browser, please click the instruction pages below). After clearing, choose preferred Journal and select login for AAN Members. You will be redirected to a login page where you can log in with your AAN ID number and password. When you are returned to the Journal, your name should appear at the top right of the page.
AAN Non-Member Subscribers
Purchase access
Disputes & Debates: Rapid online correspondence
- Author Response: Cognitive Activity and Onset Age of Incident Alzheimer Disease Dementia
- Reader Response: Cognitive Activity and Onset Age of Incident Alzheimer Disease Dementia
REQUIREMENTS
If you are uploading a letter concerning an article:
You must have updated your disclosures within six months: http://submit.neurology.org
Your co-authors must send a completed Publishing Agreement Form to Neurology Staff (not necessary for the lead/corresponding author as the form below will suffice) before you upload your comment.
If you are responding to a comment that was written about an article you originally authored:
You (and co-authors) do not need to fill out forms or check disclosures as author forms are still valid
and apply to letter.
Submission specifications:
- Submissions must be < 200 words with < 5 references. Reference 1 must be the article on which you are commenting.
- Submissions should not have more than 5 authors. (Exception: original author replies can include all original authors of the article)
- Submit only on articles published within 6 months of issue date.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- Submitted comments are subject to editing and editor review prior to posting.