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Trends in Diagnosis of Dementia Subtypes in Nationwide Medicare Claims, 2015‐2021, by Race/Ethnicity, Sex, and Neighborhood Socioeconomic Status
Jay B. Lusk, Cassie B. Ford, Beau Blass, Kim G. Johnson, Amy G. Clark, Samir Soneji, Richard O’Brien, Bradley G. Hammill et al.. Alzheimer s & Dementia, 2024-12-01
Topic: Risk, prevention and care in population studies
Abstract Background It is not well understood how incidence patterns of subtypes of Alzheimer’s disease and related dementias (ADRD) have evolved in real‐world practice. While cohort and brain bank studies provide precise biological definition of ADRD subtypes, these populations may not be representative and may not reflect how dementia is coded and diagnosed in routine clinical practice. Therefore, we sought to perform a nationally representative study of medical claims data to understand trends in diagnosis of dementia by dementia subtypes in routine clinical practice. Method We studied 100% of nationwide Medicare claims from 2014‐2021 and evaluated dementia diagnoses by specified subtypes with associated international classification of diseases (ICD) codes (Alzheimer’s disease, vascular, Lewy body, frontotemporal, alcohol induced, and not otherwise specified). We stratified results by age, sex, race/ethnicity, and neighborhood socioeconomic deprivation measured by the area deprivation index, a well‐established score that describes neighborhood socioeconomic conditions. Incidences are presented as number of new cases per 10,000 person‐years. Race/ethnicity were grouped as White, non‐Hispanic; Black, non‐Hispanic; and other race/ethnicity, concordant with other Medicare claims data analyses. Result A total of 5,721,711 patients with incident dementia were included in the study. Dementia diagnoses were more frequently coded as vascular in 2021 than 2015 (1.85 cases per 10,000 person‐years in 2015 vs 2.21 cases per 10,000 person‐years in 2021) and less frequently coded as not otherwise specified (29.1 cases per 10,000 person‐years in 2015 vs 22.17 cases per 10,000 person‐years in 2021). Coding by dementia subtype varied by race (Table 1) and sex (Table 2). Dementia diagnoses were much more frequently coded as “not otherwise specified” among beneficiaries from socioeconomically deprived neighborhoods (34.48 per 10,000 person‐years in the most deprived decile vs 25.76 in the least‐deprived decile) (Table 3). Conclusion In a national database of Medicare claims, there were substantial secular trends and differences in coding of dementia subtypes by race/ethnicity, sex, and neighborhood socioeconomic status. Secular trends in coding could reflect variation in health system performance of accurate diagnosis of dementia subtypes. Future studies should correlate claims data classifications with confirmed neuropathological classifications.
Key findings
- We stratified results by age, sex, race/ethnicity, and neighborhood socioeconomic deprivation measured by the area deprivation index, a well‐established score that describes neighborhood socioeconomic conditions.
- Result A total of 5,721,711 patients with incident dementia were included in the study.
Why it matters
This study of nationwide Medicare claims from 2014 to 2021 examined trends in diagnosis of dementia subtypes by race, ethnicity, sex, and neighborhood socioeconomic deprivation. It describes how dementia is coded and diagnosed in routine practice and does not test any treatment, cure, or prevention.
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Study details
- Participants100
- Evidence strengthModerate
How this study scored 38/100
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 (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 | 3 / 5 | Rated “moderate” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 4 / 5 | 2024 — within 3 year(s) of the newest study here |
| Sample size | 2 / 4 | 100 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 | 0 / 7 | Cited 0 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.0 citations a year over 4 year(s) since 2024 |
| Impact for its field and year | 0 / 6 | Cited 0.0× 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 0 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Emily Claire O'Brien: h-index 49 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Duke University: institution h-index 1,541 (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 | 38 / 100 | — |
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Read the original
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. 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
Lusk, J. B., Ford, C. B., Blass, B., Johnson, K. G., Clark, A. G., Soneji, S., et al. (2024). Trends in Diagnosis of Dementia Subtypes in Nationwide Medicare Claims, 2015‐2021, by Race/Ethnicity, Sex, and Neighborhood Socioeconomic Status. Alzheimer s & Dementia. https://doi.org/10.1002/alz.093412
Vancouver
Lusk JB, Ford CB, Blass B, Johnson KG, Clark AG, Soneji S, et al. Trends in Diagnosis of Dementia Subtypes in Nationwide Medicare Claims, 2015‐2021, by Race/Ethnicity, Sex, and Neighborhood Socioeconomic Status. Alzheimer s & Dementia. 2024. doi:10.1002/alz.093412.
BibTeX
@article{lusk2024-500e86e2,
author = {Lusk, Jay B. and Ford, Cassie B. and Blass, Beau and Johnson, Kim G. and Clark, Amy G. and Soneji, Samir and O’Brien, Richard and Hammill, Bradley G. and others},
title = {{Trends in Diagnosis of Dementia Subtypes in Nationwide Medicare Claims, 2015‐2021, by Race/Ethnicity, Sex, and Neighborhood Socioeconomic Status}},
journal = {Alzheimer s \& Dementia},
year = {2024},
doi = {10.1002/alz.093412},
url = {https://doi.org/10.1002/alz.093412}
}
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