Emerging evidence from a longitudinal cohort study published in JAMA Network Open suggests that exposure to common air pollutants — particularly fine particulate matter (PM₂.₅) and ozone (O₃) — is associated with adverse changes in cardiac structure and function among women with breast cancer treated with anthracyclines and/or trastuzumab.
The study followed 580 female patients (median age 50 years) who were initiating anthracycline and/or trastuzumab therapy at multiple sites within a quaternary health care system between 2010 and 2018. Over a median follow-up of 3.1 years, participants underwent 3 642 echocardiograms at standardised intervals, allowing for detailed longitudinal assessment of left ventricular (LV) function, size, and remodelling.
CLINICAL SUMMARY
What was examined
Associations between long-term exposure to ambient air pollution and cardiac structure and function in women with breast cancer treated with potentially cardiotoxic therapies, including anthracyclines and trastuzumab.
Key findings
- Higher exposure to fine particulate matter (PM₂.₅) and ozone was associated with adverse left ventricular remodelling and reduced cardiac function.
- Patients with higher pollutant exposure had an increased risk of treatment-related cardiac dysfunction.
- Associations were less consistent for PM₁₀ and nitrogen dioxide.
Clinical implications
- Environmental exposures may contribute to cardiovascular risk in patients receiving cardiotoxic cancer therapy.
- Air pollution should be considered a potential contextual risk factor alongside established clinical predictors in cardio-oncology surveillance.
Researchers examined associations between three-year average census-tract concentrations of air pollutants — including PM₂.₅, larger particulate matter (PM₁₀), nitrogen dioxide (NO₂), and ozone (O₃) — and changes in cardiac measures. The primary focus was on echocardiography-derived outcomes and the incidence of cardiac dysfunction, defined as a decline in left ventricular ejection fraction (LVEF) of 10 per cent or more to a level below 50 per cent.
PM₂.₅ and O₃ were consistently associated with adverse cardiac changes both cross-sectionally and over time. Each interquartile range (IQR) increase in PM₂.₅ (about 1.68 µg/m³) and O₃ (about 2.69 ppb) was linked with:
- Small but statistically significant reductions in LVEF (approximately -1.3 per cent and -1.4 per cent, respectively).
- Worsening longitudinal strain, an early marker of subclinical LV dysfunction.
- Increases in LV mass and volume, suggesting adverse remodelling.
Patients in the highest exposure tertiles for PM₂.₅ (adjusted hazard ratio [AHR] 2.03; 95 per cent CI, 1.17–3.52) and O₃ (AHR 2.15; 95 per cent CI, 1.23–3.78) had significantly higher risk of cardiac dysfunction compared with those in the lowest tertiles.
In contrast, PM₁₀ and NO₂ showed limited or inconsistent associations with cardiac dysfunction in this cohort, and effect sizes for these pollutants were less robust.
The findings add to evidence that environmental exposures may compound cardiovascular risk among patients undergoing potentially cardiotoxic cancer therapies, such as anthracyclines and trastuzumab. These therapies are known to carry risks of LV dysfunction and heart failure, and identifying modifiable risk factors — including air quality — is increasingly prioritised in cardio-oncology.
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The authors emphasise that the cohort was drawn from routine clinical care with rigorous echocardiographic follow-up, enhancing the relevance of the associations observed. However, the study’s observational design precludes causal inference, and pollutant exposure estimates were based on census-tract averages rather than individual measures.
While individual management of cardiac risk remains centred on traditional clinical risk factors and surveillance strategies during and after therapy, these results highlight air pollution as a potentially modifiable environmental determinant of cardiac health in oncology patients. Reducing PM₂.₅ and O₃ exposure — through public health measures or individual avoidance strategies where feasible — may warrant consideration alongside clinical monitoring and cardioprotective therapy.s
Paper: Jung W, Ko K, Smith AM, et al. Air Pollution and Cardiac Remodeling and Function in Patients With Breast Cancer. JAMA Netw Open. 2026;9(1):e2552323. doi:10.1001/jamanetworkopen.2025.52323 Access online here.
