TOPLINE:
Exposure to air pollution was linked to development of meningioma, a tumor that arises from membranes around the brain and spinal cord, in a study of nearly 4 million Danish adults. Consistent positive associations were observed between the development of meningioma and exposure to ultrafine particles (UFPs), fine particulate matter, nitrogen dioxide, and elemental carbon.
METHODOLOGY:
- The cohort study included nearly 4 million adults (mean age, 35 years; 50% women) identified from nationwide registries since 1991.
- Danish national registers were used to obtain address histories and covariates at individual and area levels.
- A validated model was used to evaluate residential air pollution, and a national emission inventory was used to quantify contributions to air pollution from local road traffic and other sources.
- The primary endpoint was occurrence of the first primary central nervous system (CNS) tumor, as reported in the Danish Cancer Registry. Cranial nerve tumors, meningiomas, gliomas, and “other CNS tumors” were included.
TAKEAWAY:
- More than 16,000 cases of CNS tumors were identified, which included gliomas (37%), meningiomas (28%), cranial nerve tumors (14%), and other CNS tumors (21%).
- 10-year mean exposure to UFPs (hazard ratio [HR] per interquartile range [IQR], 1.1), fine particulate matter (HR per IQR, 1.2), nitrogen dioxide (HR per IQR, 1.1), and elemental carbon (HR per IQR, 1.0) was associated with increased risk for meningioma.
- Sensitivity analyses showed that the HRs for meningioma were stronger for traffic-related vs nontraffic UFPs, while traffic and nontraffic fine particulate matter had similar HRs.
- No consistent associations were observed between air pollutants and risk for glioma, but a negative association was observed between cranial nerve tumors and nitrogen dioxide.
IN PRACTICE:
“Our study suggests that long-term exposure to air pollution from traffic and other sources may play a role in the development of meningioma and adds to the growing body of evidence that air pollution can affect the brain — not just the heart and lungs,” lead study author Ulla A. Hvidtfeldt, PhD, Danish Cancer Institute, Copenhagen, Denmark, said in a press release.
SOURCE:
The study was published online on July 9 in Neurology.
LIMITATIONS:
The study was limited by a strong intercorrelation and modeling uncertainty of pollutant estimates, which may have hindered the attribution of effects and led to misclassification of true personal exposure. Unmeasured factors such as genetic predisposition, ionizing radiation, and occupational or lifestyle exposures may have led to residual confounding. Additional limitations were potential ascertainment bias from differential tumor detection and reliance on emission inventories of variable quality to distinguish traffic from nontraffic sources.
DISCLOSURES:
The study was funded by the Danish Cancer Society. The investigators reported having no relevant conflicts of interest.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.