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Cognitive impairment in the U.S.: Lifetime risk, age at onset, and years impaired
Hale JM, Schneider DC, Mehta NK, Myrskylä M.. SSM - population health, 2020-03-31
Topic: Risk, prevention and care in population studies
Prior studies have analyzed the burden of cognitive impairment, but often use potentially biased prevalence-based methods or measure only years lived with impairment, without estimating other relevant metrics. We use the Health and Retirement Study (1998-2014; n = 29,304) and the preferred incidence-based Markov-chain models to assess three key measures of the burden of cognitive impairment: lifetime risk, mean age at onset, and number of years lived impaired. We analyze both mild and severe cognitive impairment (dementia) and gender, racial/ethnic, and educational variation in impairment. Our results paint a multi-dimensional picture of cognitive health, presenting the first comprehensive analysis of the burden of cognitive impairment for the U.S. population age 50 and older. Approximately two out of three Americans experience some level of cognitive impairment at an average age of approximately 70 years. For dementia, lifetime risk for women (men) is 37% (24%) and mean age at onset 83 (79) years. Women can expect to live 4.2 years with mild impairment and 3.2 with dementia, men 3.5 and 1.8 years. A critical finding is that for the most advantaged groups (i.e., White and/or higher educated), cognitive impairment is both delayed and compressed toward the very end of life. In contrast, despite the shorter lives of disadvantaged subgroups (Black and/or lower educated), they experience a younger age of onset, higher lifetime risk, and more years cognitively impaired. For example, men with at least an Associate degree have 21% lifetime dementia risk, compared to 35% among men with less than high school education. White women have 6 years of cognitively-impaired life expectancy, compared to 12 and 13 years among Black women and Latinas. These educational and racial/ethnic gradients highlight the very uneven burden of cognitive impairment. Further research is required to identify the mechanisms driving these disparities in cognitive impairment.
Key findings
- Our results paint a multi-dimensional picture of cognitive health, presenting the first comprehensive analysis of the burden of cognitive impairment for the U.S. population age 50 and older.
- For example, men with at least an Associate degree have 21% lifetime dementia risk, compared to 35% among men with less than high school education.
- White women have 6 years of cognitively-impaired life expectancy, compared to 12 and 13 years among Black women and Latinas.
Why it matters
This analysis estimated that about two out of three Americans age 50 and older experience some cognitive impairment, with lifetime dementia risk of 37% for women and 24% for men. It describes the burden and timing of cognitive impairment, including differences by race, ethnicity and education, but does not test any treatment or prevention.
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Study details
- Participants29,304
- Evidence strengthLow
How this study scored 56/100
Published in a peer-reviewed journal. Scored zero for study design, effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (SSM - population health) |
| Journal's citation record | 1 / 4 | SSM - Population Health: journal h-index 88 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 2 / 5 | 2020 — within 10 year(s) of the newest study here |
| Sample size | 4 / 4 | 29,304 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 5 / 7 | Cited 160 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 20.0 citations a year over 8 year(s) since 2020 |
| Impact for its field and year | 4 / 6 | Cited 8.2× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 2 / 6 | Cited by 7 other studies in this library |
| Still being cited | 3 / 4 | Cited 109 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Mikko Myrskylä: h-index 44 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | University of Michigan: institution h-index 2,240 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 5 institution(s) in 4 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 32300635) |
| Free to read | 2 / 2 | Free to read |
| Total | 56 / 100 | — |
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Read the original
- DOI: 10.1016/j.ssmph.2020.100577
- PubMed: 32300635
- Original source →
- Free full text: SSM - Population Health →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Hale, J. M., Schneider, D. C., Mehta, N. K., & Myrskylä, M. (2020). Cognitive impairment in the U.S.: Lifetime risk, age at onset, and years impaired. SSM - population health. https://doi.org/10.1016/j.ssmph.2020.100577
Vancouver
Hale JM, Schneider DC, Mehta NK, Myrskylä M. Cognitive impairment in the U.S.: Lifetime risk, age at onset, and years impaired. SSM - population health. 2020. doi:10.1016/j.ssmph.2020.100577. PMID: 32300635.
BibTeX
@article{hale2020-32300635,
author = {Hale, J. M. and Schneider, D. C. and Mehta, N. K. and Myrskylä, M.},
title = {{Cognitive impairment in the U.S.: Lifetime risk, age at onset, and years impaired}},
journal = {SSM - population health},
year = {2020},
doi = {10.1016/j.ssmph.2020.100577},
pmid = {32300635},
url = {https://doi.org/10.1016/j.ssmph.2020.100577}
}
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