# Exposure to particulate matters and risk of diabetes-related mortality: a systematic review and meta-analysis

## TL;DR

This study finds that exposure to fine and coarse particulate matter in air pollution is linked to increased diabetes-related deaths, especially with long-term exposure.

## Contribution

The study provides a comprehensive meta-analysis quantifying the risk of diabetes-related mortality associated with PM2.5 and PM10 exposure.

## Key findings

- PM2.5 exposure is significantly associated with diabetes-related mortality (RR = 1.123).
- Long-term PM2.5 exposure shows a stronger association (RR = 1.296).
- PM10 is also linked to increased risk, though less strongly (RR = 1.021).

## Abstract

Epidemiological evidence increasingly implicates ambient particulate matter (PM) as a contributor to diabetes progression and premature mortality; however, the strength and consistency of these associations remain uncertain. This systematic review and meta-analysis quantified the relationship between exposure to major PM fractions—particularly PM2.5 and PM10—and the risk of diabetes-related mortality in adult populations.

Following PRISMA and MOOSE guidelines, five databases were searched through September 30, 2025. Eligible observational studies assessed long- or short-term exposure to ambient PM and reported quantitative estimates for diabetes-associated deaths. Effect sizes were pooled using random-effects models and expressed as relative risk (RR) per 10 µg/m3 increment in PM concentration. Subgroup and meta-regression analyses explored sources of heterogeneity.

Thirty-six studies (41 datasets) were included. Pooled analysis showed a significant positive association between PM2.5 exposure and diabetes-related mortality (RR = 1.123; 95%CI: 1.099–1.147; I2 = 95.3%). The effect was stronger for long-term exposure (RR = 1.296; 95%CI: 1.197–1.395) and prospective cohorts (RR = 1.327; 95%CI: 1.189–1.466). PM10 was also associated with increased risk, though with smaller magnitude (RR = 1.021; 95%CI: 1.007–1.035; I2 = 81.7%). Meta-regression confirmed exposure duration as a significant modifier (p = 0.014).

Both fine (PM2.5) and coarse (PM10) particulate matter are significantly associated with increased diabetes-related mortality, with the strongest and most consistent effects observed for chronic PM2.5 exposure. These findings highlight the metabolic health burden of air pollution and underscore the importance of stringent air-quality standards to reduce premature diabetes deaths globally.

The online version contains supplementary material available at https://doi.org/10.1265/ehpm.25-00424.