MONDAY, Jan. 26, 2026 (HealthDay News) -- Air pollution is associated with an increased risk for developing motor neuron disease (MND) and disease progression after diagnosis, according to a study published online Jan. 20 in JAMA Neurology.Jing Wu, Ph.D., from Karolinska Institutet in Stockholm, and colleagues examined whether long-term exposure to air pollution is associated with the risk and prognosis of MND in a population-based, nested case-control study using Swedish health register data of incident MND cases diagnosed between 2015 and 2023 with up to eight years of follow-up. Participants included patients with MND, five age- and sex-matched population controls without MND per patient, and full siblings of the patients with MND (1,463 patients, 7,310 population controls, and 1,768 sibling controls).The researchers found that long-term air pollution was associated with an increased risk for MND in the population comparison, with odds ratios of 1.21, 1.30, 1.29, and 1.20 per interquartile range increase in the 10-year average level of particulate matter with a diameter of ≤2.5 µm (PM2.5), PM2.5-10, PM10, and nitrogen dioxide (NO2). A higher hazard of mortality was seen in association with a higher level of PM10 or NO2, while faster functional decline, particularly motor and respiratory functions, was seen in association with a higher level of all PMs after MND diagnosis."These results highlight the public health importance of improving air quality to reduce the risk of neurodegenerative diseases and to improve the outcome of patients with these diseases," the authors write.Several authors disclosed ties to the biopharmaceutical industry.Abstract/Full Text (subscription or payment may be required)Editorial (subscription or payment may be required).Sign up for our weekly HealthDay newsletter