Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 55 1 2026 02 08 151 161 Azam Rahimzadeh kalaleh Nursing Research Center of Respiratory Diseases (NRCRD), National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran Fatemeh Bahrambeygi Nursing Research Center of Respiratory Diseases (NRCRD), National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran Saeid Besharati Nursing Research Center of Respiratory Diseases (NRCRD), National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran Masoumeh Nomani Research Center of Thoracic Oncology (RCTO), National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran Zobeydeh Saeed Nursing Research Center of Respiratory Diseases (NRCRD), National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran 2025 05 20 2025 10 19 Background: Air pollution is an important global public health concern with multiple consequences for the individuals with respiratory diseases. We aimed to assess the influence of air pollution variables on the hospitalization rates of individuals with chronic obstructive pulmonary disease (COPD). Methods: Atmospheric pollutant parameters, such as NO2, SO2, CO, O3, PM₂.₅, PM10, and AQI, from Mar 2022 to Mar 2024 were measured. The information of COPD patients was extracted from Masih Daneshvari Hospital (referral center for respiratory diseases in Tehran). The relationship among data, Relative Risk (RR), and Attributable Proportion (AP) for prolonged exposure to air pollutants during a biennial period was assessed using the Air Quality Plus (2.2.4) software. Results: March 2023 saw the highest number of hospitalizations, with an average of 4.16 cases. This was concurrent with an elevation in PM₂.₅ concentrations. Furthermore, the month of Aug 2023 exhibited a high hospitalization rate, with an average of 3.8 cases, linked to the rise in the concentration of PM₂.₅, NO2, and O3 air pollutants. The highest mean relative risks (RRs) associated with acute exacerbation of COPD were as follows: (PM10: 1.83, PM₂.₅: 1.76). Conclusion: High levels of air pollution, specially PM₂.₅, significantly worsen COPD conditions and are a main trigger for COPD exacerbation. Consequently, enforcing more stringent air quality regulations is an essential public health approach to alleviate the incidence of COPD. https://ijph.tums.ac.ir/index.php/ijph/article/view/39189 https://ijph.tums.ac.ir/index.php/ijph/article/download/39189/8755