ArticleJournal of Alzheimer's disease : JAD2023
PM2.5 and Dementia in a Low Exposure Setting: The Influence of Odor Identification Ability and APOE.
Article in Journal of Alzheimer's disease : JAD, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers, 2 of them syntheses that pooled it.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
9 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- A systematic review with a Burden of Proof meta-analysis of health effects of long-term ambient fine particulate matter (PMNature aging · 2025Pooled it
- Beneficial Effect of Societal Factors on APOE-ε2 and ε4 Carriers' Brain Health: A Systematic Review.The journals of gerontology. Series A, Biological sciences and medical sciences · 2024Pooled it
- Air Pollution and Alzheimer's Disease: A Systematic Review and Meta-Analysis.Journal of clinical medicine · 2026Review
- Racial and ethnic differences in the impact of air pollution on the risk of Alzheimer's disease and related dementias in the Multiethnic Cohort Study.Environment international · 2026Article
- The sex-specific association between long-term PM2.5 exposure and incident dementia in community-dwelling older adults in Australia.Alzheimer's & dementia : the journal of the Alzheimer's Association · 2026Article
- Associations between air pollution and relative leukocyte telomere length among northern Swedish adults based on findings from the Betula study.Scientific reports · 2025Article
- The impact of APOE4 on neurological symptoms after exposure to K. brevis neurotoxin.Environmental toxicology and pharmacology · 2025Article
- Exposure to source-specific air pollution in residential areas and its association with dementia incidence: a cohort study in Northern Sweden.Scientific reports · 2024Article
- Metabolic profiles associated with exposure to ambient particulate air pollution: findings from the Betula cohort.Frontiers in public health · 2024Article
Corrections and comments
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Authors and funding
7 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundGrowing evidence show that long term exposure to air pollution increases the risk of dementia.
objectiveThe aim of this study was to investigate associations between PM2.5 exposure and dementia in a low exposure area, and to investigate the role of olfaction and the APOE ɛ4 allele in these associations.
methodsData were drawn from the Betula project, a longitudinal study on aging, memory, and dementia in Sweden. Odor identification ability was assessed using the Scandinavian Odor Identification Test (SOIT). Annual mean PM2.5 concentrations were obtained from a dispersion-model and matched at the participants' residential address. Proportional hazard regression was used to calculate hazard ratios.
resultsOf 1,846 participants, 348 developed dementia during the 21-year follow-up period. The average annual mean PM2.5 exposure at baseline was 6.77μg/m3, which is 1.77μg/m3 above the WHO definition of clean air. In a fully adjusted model (adjusted for age, sex, APOE, SOIT, cardiovascular diseases and risk factors, and education) each 1μg/m3 difference in annual mean PM2.5-concentration was associated with a hazard ratio of 1.23 for dementia (95% CI: 1.01-1.50). Analyses stratified by APOE status (ɛ4 carriers versus non-carriers), and odor identification ability (high versus low), showed associations only for ɛ4 carriers, and for low performance on odor identification ability.
conclusionPM2.5 was associated with an increased risk of dementia in this low pollution setting. The associations between PM2.5 and dementia seemed stronger in APOE carriers and those with below average odor identification ability.
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