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Incidence of Alzheimer’s disease (AD) dementia and mild cognitive impairment (MCI) in the United States Medicare population
Haixin Zhang, Quanwu Zhang, Amir Abbas Tahami Monfared. Alzheimer s & Dementia, 2023-12-01
Topic: Risk, prevention and care in population studies
Abstract Background Alzheimer’s disease (AD) is a chronic, neurodegenerative condition. Mild cognitive impairment (MCI) is characterized by cognitive decline, without dementia. We aimed to estimate the incidence of AD and MCI among Medicare beneficiaries. Method Patients were identified from the US Center for Medicare and Medicaid Services (CMS) database using International Classification of Diseases (ICD) codes for AD (331.0, G30.9, G30.8, or G30.1,) and MCI (331.83 or G31.84). Both AD and MCI were identified using the search rule of 2 ICD codes ≥30 days apart ≤365 days from both Medicare fee‐for‐service (FFS: 2008‐2018) and Medicare Advantage (MA: 2015‐2018). US regions were derived using zip codes and categorized by National Center for Chronic Disease Prevention/Health Promotion regions. Yearly incidence was defined as the number of new cases of AD or MCI in each year divided by the population at risk in the year. Confidence intervals were not reported due to small intervals. Result The incidence of AD and MCI per 10,000 person‐years was 82.9 and 4.9, 80.3 and 7.4, 74.5 and 9.3, 69.8 and 10.9, 65.3 and 13.4, 62.8 and 15.8, 60.7 and 17.4, 65.5 and 20.7, 61.4 and 22.4, 56.0 and 22.9, and 52.2 and 23.2 spanning from 2008 through 2018, respectively. In 2018, the incidence of AD and MCI per 10,000 person‐years by demographic subgroups was: 43 and 21 for men and 59 and 25 for women; 16 and 10 among those aged 65‐69 years, 30 and 18 for ages 70‐74 years, 58 and 30 for ages 75‐79, 102 and 44 for ages 80‐84, 176 and 57 for age ≥85 years old; 56 and 26 for Whites, 38 and 13 for Blacks, and 43 and 15 for Asians. The incidence of AD and MCI per 10,000 person‐years in 2018 was highest in the US Northeast, especially in New Hampshire (77 and 39), Vermont (74 and 47), and New Jersey (73 and 33). Conclusion Among Medicare beneficiaries from 2008 to 2018, AD incidence generally decreased while MCI increased. Women, older age, White race, and Northeast region were associated with higher incidence of AD and MCI in 2018.
Key findings
- Result The incidence of AD and MCI per 10,000 person‐years was 82.9 and 4.9, 80.3 and 7.4, 74.5 and 9.3, 69.8 and 10.9, 65.3 and 13.4, 62.8 and 15.8, 60.7 and 17.4, 65.5 and 20.7, 61.4 and 22.4, 56.0 and 22.9, and 52.2 and 23.2 spanning from 2008 through 2018, respectively.
- Women, older age, White race, and Northeast region were associated with higher incidence of AD and MCI in 2018.
Why it matters
This study estimated the incidence of Alzheimer's disease and mild cognitive impairment among Medicare beneficiaries, finding that incidence per 10,000 person-years declined for Alzheimer's disease and increased for mild cognitive impairment from 2008 through 2018. Women, older age, White race, and Northeast region were associated with higher incidence of Alzheimer's disease and mild cognitive impairment in 2018.
Study details
- Evidence strengthLow
How this study scored 30/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Alzheimer s & Dementia) |
| Journal's citation record | 2 / 4 | Alzheimer s & Dementia: journal h-index 228 (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 | 3 / 5 | 2023 — within 6 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 1 / 7 | Cited 1 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.2 citations a year over 5 year(s) since 2023 |
| Impact for its field and year | 1 / 6 | Cited 0.2× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 0 / 4 | Cited 1 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Amir Abbas Tahami Monfared: h-index 20 (OpenAlex, whole career) |
| Institution's track record | 0 / 3 | Eisai (United States): institution h-index 251 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 1 / 2 | Not in PubMed, but has a DOI |
| Free to read | 2 / 2 | Free to read |
| Total | 30 / 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. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Zhang, H., Zhang, Q., & Monfared, A. A. T. (2023). Incidence of Alzheimer’s disease (AD) dementia and mild cognitive impairment (MCI) in the United States Medicare population. Alzheimer s & Dementia. https://doi.org/10.1002/alz.077092
Vancouver
Zhang H, Zhang Q, Monfared AAT. Incidence of Alzheimer’s disease (AD) dementia and mild cognitive impairment (MCI) in the United States Medicare population. Alzheimer s & Dementia. 2023. doi:10.1002/alz.077092.
BibTeX
@article{zhang2023-6c84f580,
author = {Zhang, Haixin and Zhang, Quanwu and Monfared, Amir Abbas Tahami},
title = {{Incidence of Alzheimer’s disease (AD) dementia and mild cognitive impairment (MCI) in the United States Medicare population}},
journal = {Alzheimer s \& Dementia},
year = {2023},
doi = {10.1002/alz.077092},
url = {https://doi.org/10.1002/alz.077092}
}
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