Environmental Health Engineering and Management Journal

fa The Relationship Between Short-Term and Long-Term Effects of Air Pollution on Stroke Morbidity in Arak, Iran: Time Series Zero-Inflated Negative Binomial Regression عمومى General مقاله اصیل Original Article <div style="text-align: justify;">Background: Stroke, a leading cause of mortality and disability worldwide, is influenced by both nonmodifiable and modifiable risk factors, including air pollution. Arak, Iran, is one of the country’s most industrialized and polluted cities. This study investigates the association between short-term and longterm exposure to major air pollutants—PM2.5, PM₁₀, O₃, SO₂, and NO₂—and stroke morbidity.<br> Methods: This prospective cohort study included all stroke patients registered in Arak between 2019 and 2022. Air pollutant concentrations were obtained from four monitoring stations, with short-term exposures defined as 1 week, 1 month, 3 months, and 6 months, and long-term exposures as 9, 12, 18, and 24 months. Data were analyzed using a time-series zero-inflated negative binomial regression model, adjusting for confounders including smoking and opium use.<br> Results: Short-term (3-month) exposure to NO₂, O₃, and SO₂ was significantly associated with increased stroke incidence, while short-term (1-week) exposure to these pollutants showed a negative association. PM₁₀ and O₃ (6 months) and SO₂ (1–3 months) also demonstrated significant associations. Long-term (2-year) exposure to PM₁₀, NO₂, and SO₂ was strongly associated with stroke morbidity, whereas O₃ exposure showed an inverse relationship. PM2.5 was not significantly associated in the short term but showed a positive, though nonsignificant, association in the long term.<br> Conclusion: Both short-term and long-term exposure to certain air pollutants are associated with stroke morbidity, with varying effects by pollutant and lag period. Reducing chronic exposure to PM₁₀, NO₂, and SO₂ may help lower the incidence of stroke in high-pollution settings.</div> Air pollution, Stroke, Epidemiology, Morbidity, Arak 1 8 http://ehemj.com/browse.php?a_code=A-10-1-430&slc_lang=fa&sid=1 Leila Poorsaadat leilamd@yahoo.com 100319475328460021290 100319475328460021290 No Department of Neurology, School of Medicine, Arak University of Medical Sciences, Arak, Iran Amir Almasi-Hashiani amiralmasi2007@gmail.com 100319475328460021291 100319475328460021291 No Department of Epidemiology, Faculty of Health, Arak University of Medical Sciences, Arak, Iran Payam Amini p.amini@keele.ac.uk 100319475328460021292 100319475328460021292 No School of Medicine, Keele University, Keele, Staffordshire, UK Ali Koolivand akulivand@gmail.com 100319475328460021293 100319475328460021293 No Student Research Committee, Arak University of Medical Sciences, Arak, Iran Maede Nasrollahi maede1997@yahoo.com 100319475328460021294 100319475328460021294 No Student Research Committee, Arak University of Medical Sciences, Arak, Iran Seyed Hamed Mirhoseini dr.mirhoseini@arakmu.ac.ir 100319475328460021295 100319475328460021295 Yes Correspondence to: Department of Environmental Health Engineering, Faculty of Health, Arak University of Medical Sciences, Arak, Iran