Effect of long-term exposure to ozone on type 2 diabetes mellitus: A meta-analysis of cohort studies
- VernacularTitle:长期臭氧暴露与2型糖尿病发病风险的队列研究的meta分析
- Author:
Shaojuan ZHANG
1
;
Yongle LIU
2
;
Zhuanguo YANG
1
;
Jinyang WANG
3
Author Information
- Publication Type:Investigation
- Keywords: ozone; type 2 diabetes; cohort study; long-term exposure; meta-analysis
- From: Journal of Environmental and Occupational Medicine 2026;43(1):43-50
- CountryChina
- Language:Chinese
- Abstract: Background The global number of type 2 diabetes (T2D) cases has been steadily increasing over the past few decades, becoming a major public health issue. Available toxicological research has indicated that ozone (O3) can lead to oxidative stress and inflammatory responses, thereby causing metabolic changes and the development of T2D. Existing cohort studies on the impact of long-term O3 exposure on the risk of developing T2D have reached contradictory conclusions, and the results have shown significant heterogeneity. Objective To summarize cohort studies on long-term O3 exposure and T2D risk, and investigate heterogeneity sources in the association between O3 and T2D. Methods Cohort studies on O3 and T2D were searched through PubMed, Embase, and the Web of Science, with the search deadline set for 25 April, 2025. After two researchers independently screened the literature, extracted data, and evaluated the quality of the included studies, meta-analysis was conducted using Stata 18.0 software. We used a random effects model to calculate the overall relative risk (RR) of the standardized risk estimates and its 95% confidence interval (CI). Additionally, sensitivity analysis, subgroup analysis, meta-regression, and publication bias testing were performed to explore the sources of heterogeneity in the association between O3 and T2D. Results In the 8 articles meeting predetermined inclusion criteria, a total of 11 cohort studies involving 54887070 participants were finally included. The results of the meta-analysis indicated that long-term exposure to O3 was associated with a higher incidence of type 2 diabetes [standardized RR=1.04 (95%CI: 1.01, 1.07), P<0.001, I2=97.3%], and significant heterogeneity existed. The subgroup analysis showed that females (standardized RR=1.08, 95%CI: 1.03, 1.13) and the Asian population (standardized RR=1.09, 95%CI: 1.06, 1.11) were are more susceptible to O3. The meta-regression model that included study region and average O3 concentration variables explained 60.33% of the heterogeneity between studies. No significant evidence of publication bias was observed after the funnel plot test, Egger's test (P=0.437), Begg's test (P=0.640), and the trim-and-fill method. Conclusion Long-term exposure to O3 could increase the risk of developing T2D, with females and Asian populations being particularly sensitive. The heterogeneity in the association between O3 and T2D can be partly explained by factors such as average O3 concentration and geographic location.
