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45/100

✓ Peer-reviewed alzhub usefulness score 45 out of 100. Disparities

Topic: Risk, prevention and care in population studies

High Resolution Image Download MS PowerPoint Slide Fine particulate matter (PM 2.5 ) is linked to dementia risk, but ultrafine particles (UFPs, <100 nm) may be even more toxic due to their distinct physicochemical properties. However, evidence on UFPs and dementia remains limited. This study assessed the association between UFP exposure and Alzheimer’s disease (AD) and related dementias (ADRD) among U.S. older adults. Using Medicare data, we analyzed ZIP code-level UFP exposure in 2017 for beneficiaries aged 65 and older residing in the contiguous U.S., applying Cox proportional hazard models to estimate AD and ADRD incidence (2018–2020) while considering comorbidities. Among ∼21 million participants for AD and ∼20 million for ADRD, each interquartile range increase in UFP exposure (3701.6 and 3668.5 particles/cm 3, respectively) was associated with higher AD (HR: 1.026, 95% CI: 1.014–1.038) and ADRD (HR: 1.016, 95% CI: 1.008–1.023) risks. The association was linear within typical exposure levels and stronger in individuals with comorbidities. Geographically, the UFP-associated dementia risk was higher in rural areas than in urban areas, possibly due to different pollution sources. These findings underscore UFPs as neurotoxicants and highlight the need for targeted public health interventions to protect vulnerable populations.

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APA 7th

Zhu, Q., Deng, Y.-L., Liu, Y., & Steenland, K. (2025). Associations between Ultrafine Particles and Incident Dementia in Older Adults. Environmental Science & Technology. https://doi.org/10.1021/acs.est.4c10574

Vancouver

Zhu Q, Deng Y.-L, Liu Y, Steenland K. Associations between Ultrafine Particles and Incident Dementia in Older Adults. Environmental Science & Technology. 2025. doi:10.1021/acs.est.4c10574. PMID: 40079183.

BibTeX

@article{zhu2025-40079183,
  author  = {Zhu, Qiao and Deng, Yan-Ling and Liu, Yang and Steenland, Kyle},
  title   = {{Associations between Ultrafine Particles and Incident Dementia in Older Adults}},
  journal = {Environmental Science \& Technology},
  year    = {2025},
  doi     = {10.1021/acs.est.4c10574},
  pmid    = {40079183},
  url     = {https://doi.org/10.1021/acs.est.4c10574}
}

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Key findings

Among ∼21 million participants for AD and ∼20 million for ADRD, each interquartile range increase in UFP exposure (3701.6 and 3668.5 particles/cm 3, respectively) was associated with higher AD (HR: 1.026, 95% CI: 1.014–1.038) and ADRD (HR: 1.016, 95% CI: 1.008–1.023) risks.
These findings underscore UFPs as neurotoxicants and highlight the need for targeted public health interventions to protect vulnerable populations.

Why it matters

Among about 21 million Medicare participants, each interquartile range increase in ultrafine particle exposure was linked to slightly higher risks of Alzheimer's disease and related dementias. This identifies a possible environmental risk factor and calls for public health interventions, but does not test any treatment, cure, or prevention.

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Study details

Effect sizeHR: 1.026; HR: 1.016
Evidence strengthLow

How this study scored 45/100

Published in a peer-reviewed journal. Scored zero for study design, sample size, 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 (Environmental Science & Technology)
Journal's citation record	4 / 4	Environmental Science & Technology: journal h-index 592 (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	4 / 5	2025 — within 3 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	3 / 3	Effect reported with a statistic (interval, p-value, ratio or similar)
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	2 / 7	Cited 13 times (OpenAlex, 2026-10-10)
Citations per year	2 / 5	4.3 citations a year over 3 year(s) since 2025
Impact for its field and year	3 / 6	Cited 5.3× 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	1 / 4	Cited 13 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record	3 / 4	Last-listed author Kyle Steenland: h-index 91 (OpenAlex, whole career)
Institution's track record	1 / 3	Emory University: institution h-index 1,360 (OpenAlex)
Multi-centre collaboration	0 / 3	OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete)
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 40079183)
Free to read	2 / 2	Free to read
Total	45 / 100	—

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