Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2025 Oct 21;25(1):3548.
doi: 10.1186/s12889-025-24560-9.

The association between air pollution and cognitive impairment: a systematic review and meta- analysis of global studies

Abebe Kassa Geto  1 , Sefineh Fenta Feleke  2 , Ali Yimer  2 , Atitegeb Abera Kidie  2 , Natnael Amare Tesfa  3 , Esuyawkal Mislu  4 , Hassen Ahmed Yesuf  5 , Molla Hailu  5 , Birtukan Gizachew Ayal  2
Affiliations
Meta-Analysis

The association between air pollution and cognitive impairment: a systematic review and meta- analysis of global studies

Abebe Kassa Geto et al. BMC Public Health. .

Abstract

Introduction: Air pollution remains one of the most significant global health threats, affecting populations everywhere. Its widespread and persistent presence has long posed serious risks, and its far-reaching effects underscore the significant threat it poses to public health. Although numerous investigations have been conducted worldwide, their outcomes have remained inconsistent and lacked definitive conclusions. Therefore, this systematic review and meta-analysis sought to determine the association between air pollution and cognitive impairment across the globe.

Methods: Databases such as PubMed/MEDLINE, Jane, Science Direct, Cochrane Library, LIVIVO, CINAHL, Global Index Medicus, African Journals Online, Web of Science, HINARI, Semantic Scholar, Google, and Google Scholar were used to retrieve all the relevant articles. Data were analyzed using STATA 17 software to determine the pooled associations between air pollution and cognitive impairment with a 95% confidence interval using a random-effects model. Moreover, the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA 2020) guidelines were followed for this study.

Result: Fifty-four articles with 711,918 study participants were included in this meta-analysis to determine the association between air pollution and cognitive impairment. The findings of the study indicated that for every 1 µg/m3 increase in PM2.5, PM10, PM1 and black carbon concentration, the cognitive function was decreased by - 0.79 (95% CI β: -0.90, -0.68; I2 = 0.0% and p = 0.730), - 0.48 (95% CI β: -0.82, -0.15; I2 = 99.99% and p = 0.00), - 0.90 (95% CI β: -0.97, -0.82; I2 = 94.60% and p = 0.00), and - 0.53 (95% CI β: -1.03, -0.02; I2 = 99.44% and p = 0.00) respectively. Moreover, the pooled odds of developing cognitive impairment following exposure to a 1 µg/m3 increment in concentration of PM2.5 was 1.02 (95% CI OR: 1.01, 1.02; I2 = 97.02% and p = 0.00).

Conclusion: Exposure to particulate matter air pollutants such as PM2.5, PM10, PM1, and black carbon was associated with an increased risk of cognitive impairment. The results may have substantial public health significance for preventing cognitive impairment through strong air pollution interventions.

Keywords: Air pollution; Association; Black carbon; Cognitive impairment; Particulate matter.

PubMed Disclaimer

Conflict of interest statement

Declarations. Ethics approval and consent to participate: Not Applicable. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
A PRISMA flow chart showing study selection for systematic review and meta-analysis of the association between air pollution and cognitive impairment of global studies, 2025
Fig. 2
Fig. 2
Forest plot showing the pooled association between PM2.5 and cognitive function among global studies in terms of beta coefficient, 2025
Fig. 3
Fig. 3
Forest plot showing the pooled association between PM10 and cognitive function among global studies in terms of beta coefficient, 2025
Fig. 4
Fig. 4
Forest plot showing the pooled association between PM1 and cognitive function among global studies in terms of beta coefficient, 2025
Fig. 5
Fig. 5
Forest plot showing the pooled association between black carbon and cognitive function among global studies in terms of beta coefficient, 2025
Fig. 6
Fig. 6
A funnel plot to test the publication bias of the included studies in the meta-analysis of the association between PM2.5 and cognitive function in terms of beta coefficient, 2025
Fig. 7
Fig. 7
A funnel plot displaying the result of the simulated meta-analysis of the association between PM2.5 and cognitive function in terms of beta coefficient, 2025
Fig. 8
Fig. 8
Sensitivity analysis result of the included studies for the pooled association between PM2.5 and cognitive function in terms of beta coefficient, 2025
Fig. 9
Fig. 9
Subgroup analysis by county category for the pooled association between PM2.5 and cognitive function in terms of odds ratio, 2025
Fig. 10
Fig. 10
Subgroup analysis by continent for the pooled association between PM2.5 and cognitive function in terms of odds ratio, 2025
Fig. 11
Fig. 11
Subgroup analysis by country category for the pooled association between PM10 and cognitive function in terms of beta coefficient, 2025
Fig. 12
Fig. 12
Subgroup analysis by continent for the pooled association between PM10 and cognitive function in terms of beta coefficient, 2025
See this image and copyright information in PMC

References

    1. Tan L, Nakanishi E, Lee M. Association between exposure to air pollution and late-life neurodegenerative disorders: an umbrella review. Environ Int. 2022;158:106956.
    1. Newby DE, Mannucci PM, Tell GS, Baccarelli AA, Brook RD, Donaldson K, et al. Expert position paper on air pollution and cardiovascular disease. Eur Heart J. 2015;36(2):83–93. - PMC - PubMed
    1. Walters R, Air, Pollution. Climate Change and International (in) Action. In: Blaustein J, Fitz-Gibbon K, Pino NW, White R, editors. The Emerald Handbook of Crime, Justice and Sustainable Development. Emerald Publishing Limited; 2020. p. 533–49.
    1. Awe YA, Larsen BK, Sanchez-Triana E. The Global Health Cost of PM2. 5 Air Pollution: A Case for Action Beyond 2021. 2022.
    1. Vos T, Lim SS, Abbafati C, Abbas KM, Abbasi M, Abbasifard M, et al. Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the global burden of disease study 2019. Lancet. 2020;396(10258):1204–22. - PMC - PubMed

MeSH terms

LinkOut - more resources