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Ambient Air Pollution and Parkinson's Disease and Alzheimer's Disease: An Updated Meta-Analysis
Cuiyao Xie, Xi Xia, Kai Wang, Jie Yan, Lijun Bai, Liqiong Guo, Xiaoxue Li, Shaowei Wu. Toxics, 2025-02-15
Topic: Air pollution and environmental exposures
In total, 42 eligible studies were included. For each 5 μg/m3 increase in long-term PM2.5 exposure, the odds ratios (ORs) were 1.16 (95% CI: 1.04, 1.30; I2 = 95%) and 1.10 (95% CI: 1.03, 1.17; I2 = 95%) for AD and PD, respectively. For each 5 μg/m3 increase in short-term PM2.5 exposure, the OR was 1.01 (95% CI: 1.002, 1.01; I2 = 77%) for PD. For each 1 ppb increase in long-term NO2 exposure, the OR was 1.01 (95% CI: 1.0002, 1.02; I2 = 79%) for PD. Ambient air pollution, particularly PM2.5, may contribute to the increased risks of neurodegenerative diseases including AD and PD.
Key findings
- In total, 42 eligible studies were included.
- For each 5 μg/m3 increase in long-term PM2.5 exposure, the odds ratios (ORs) were 1.16 (95% CI: 1.04, 1.30; I2 = 95%) and 1.10 (95% CI: 1.03, 1.17; I2 = 95%) for AD and PD, respectively.
- For each 5 μg/m3 increase in short-term PM2.5 exposure, the OR was 1.01 (95% CI: 1.002, 1.01; I2 = 77%) for PD.
- For each 1 ppb increase in long-term NO2 exposure, the OR was 1.01 (95% CI: 1.0002, 1.02; I2 = 79%) for PD.
- Ambient air pollution, particularly PM2.5, may contribute to the increased risks of neurodegenerative diseases including AD and PD.
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Study details
- Study designmeta-analysis
- Evidence strengthHigh
How this study scored 71/100
Published in a peer-reviewed journal, and it is a meta-analysis pooling many studies. Scored zero for sample size, effect reported and studied in people 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, cited by studies here, 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 56 points we could judge it on, which is 71 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Toxics) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| Study design | 12 / 12 | A meta-analysis pooling many studies |
| 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 | 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 | 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 | A review of other studies — randomisation is not credited here |
| 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 | — / 6 | Not yet checked against this library's citation graph — left out of this score |
| 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 | 2 / 2 | Indexed in PubMed (PMID 39997954) |
| Free to read | — / 2 | Access not recorded — left out of this score |
| Points | 40 / 56 | Scored on 10 of 20 parts. We have no data for the rest, so they are left out: 40 of the 56 points we could judge it on is 71 out of 100. |
| Total | 71 / 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. The record names 8 authors; APA and Vancouver show the first six, BibTeX and the downloads carry all of them. Check the citation against the original before you use it.
APA 7th
Xie, C., Xia, X., Wang, K., Yan, J., Bai, L., Guo, L., et al. (2025). Ambient Air Pollution and Parkinson's Disease and Alzheimer's Disease: An Updated Meta-Analysis. Toxics. https://doi.org/10.3390/toxics13020139
Vancouver
Xie C, Xia X, Wang K, Yan J, Bai L, Guo L, et al. Ambient Air Pollution and Parkinson's Disease and Alzheimer's Disease: An Updated Meta-Analysis. Toxics. 2025. doi:10.3390/toxics13020139. PMID: 39997954.
BibTeX
@article{xie2025-39997954,
author = {Xie, Cuiyao and Xia, Xi and Wang, Kai and Yan, Jie and Bai, Lijun and Guo, Liqiong and Li, Xiaoxue and Wu, Shaowei},
title = {{Ambient Air Pollution and Parkinson's Disease and Alzheimer's Disease: An Updated Meta-Analysis}},
journal = {Toxics},
year = {2025},
doi = {10.3390/toxics13020139},
pmid = {39997954},
url = {https://doi.org/10.3390/toxics13020139}
}
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