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A Comparison of the Prevalence of Dementia in the United States in 2000 and 2012
Langa KM, Larson EB, Crimmins EM, et al.. JAMA Internal Medicine, 2017-01-01
Topic: Risk, prevention and care in population studies
Comparing two nationally representative surveys of older Americans 12 years apart, researchers found the share of seniors with dementia fell substantially, from 11.6% in 2000 to 8.8% in 2012. This happened even though obesity, diabetes, and hypertension all became more common in that period, and coincided with a rise in average years of education among older adults, which the authors link to lower dementia risk.
Key findings
- Dementia prevalence in US adults 65+ fell from 11.6% (2000) to 8.8% (2012), a statistically significant decline (P<.001)
- Average educational attainment rose from 11.8 to 12.7 years between the two survey waves
- The prevalence decline occurred despite increases in obesity, diabetes, and hypertension among older adults
- More years of education was associated with lower dementia risk within the analysis
Why it matters
This study compared dementia prevalence in the United States in 2000 and 2012 using nationally representative survey data. It examines population trends in dementia prevalence and does not test any treatment, cure, or prevention.
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Study details
- Study designcross-sectional
- Participants21,057
- Effect sizeDementia prevalence declined from 11.6% (95% CI 10.7%-12.7%) in 2000 to 8.8% (95% CI 8.2%-9.4%) in 2012 (age/sex-standardized 8.6%)
- Evidence strengthHigh
Limitations
Based on two cross-sectional survey waves rather than continuous surveillance of the same individuals, so changes in survey methodology, response patterns, or cognitive testing procedures cannot be fully ruled out as contributors to the observed decline.
How this study scored 65/100
Published in a leading specialty journal, and it is a snapshot of people at one point in time. Scored zero for randomised / blinded and indexed in PubMed because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, still being cited, senior author's track record, institution's track record, multi-centre collaboration and free to read, so those were left out: it earned 40 of the 62 points we could judge it on, which is 65 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (JAMA Internal Medicine) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| Study design | 4 / 12 | A snapshot of people at one point in time |
| Strength of evidence | 5 / 5 | Rated “high” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 2 / 5 | 2017 — within 10 year(s) of the newest study here |
| Sample size | 4 / 4 | 21,057 participants |
| Effect reported | 3 / 3 | Effect reported with a statistic (interval, p-value, ratio or similar) |
| 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 | — / 7 | No citation count (not found in OpenAlex) — left out of this score |
| Citations per year | — / 5 | No citation count or no year — left out of this score |
| Impact for its field and year | — / 6 | No field-weighted citation impact (OpenAlex has none yet) — left out of this score |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | — / 4 | No yearly citation counts — left out of this score |
| Senior author's track record | — / 4 | Senior author's record not available — left out of this score |
| Institution's track record | — / 3 | No institution listed in OpenAlex — left out of this score |
| Multi-centre collaboration | — / 3 | Institutions not listed — left out of this score |
| Indexed in PubMed | 0 / 2 | No PubMed ID and no DOI — scores zero (not stated in the record — scored 0) |
| Free to read | — / 2 | Access not recorded — left out of this score |
| Points | 40 / 62 | Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 40 of the 62 points we could judge it on is 65 out of 100. |
| Total | 65 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
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Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. This record has no DOI, so the citation leaves it out. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Langa, K. M., Larson, E. B., Crimmins, E. M., et al. (2017). A Comparison of the Prevalence of Dementia in the United States in 2000 and 2012. JAMA Internal Medicine.
Vancouver
Langa KM, Larson EB, Crimmins EM, et al. A Comparison of the Prevalence of Dementia in the United States in 2000 and 2012. JAMA Internal Medicine. 2017. PMID: 27893041.
BibTeX
@article{langa2017-21fefbb4,
author = {Langa, K. M. and Larson, E. B. and Crimmins, E. M. and others},
title = {{A Comparison of the Prevalence of Dementia in the United States in 2000 and 2012}},
journal = {JAMA Internal Medicine},
year = {2017},
pmid = {27893041}
}
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