Comparisons between Chronic Obstructive Pulmonary Disease related to Wood Smoke (raised by Baking Bread) and Tobacco Smoking

Introduction: Chronic obstructive pulmonary disease (COPD) is progressive limitation of airflow and decline in lung function. Although tobacco smoke is the main risk factor for COPD, air contamination by wood burning smoke is another important one. Approximately half of the world’s population use this source of energy for cookingand heating; especially in developing countries, like Iran. It remains unclear if COPD due to wood smoke raised by baking bread (COPD-B) and that caused bytobacco smoking (COPD-S) have different characteristics and clinical presentation. Our objective was to describe these differences. Materials and Methods:This cross-sectional study was performed in Afshar COPD clinic, part of the Shahid Sadoughi University of Medical Sciences, Yazd, Iran. The clinical records of 231 patients with diagnosis of COPD were reviewed. After considering inclusion and exclusion criteria, 91 patients (46 with COPD-B and 45 with COPDS) underwent physical examination and para-clinical assessments (respiratory function tests, Chest X-ray and quality of life). Results: COPD-B patients are mostly women, older and had higher FEV1/FVC percent andFEF25-75, but had fewer post-bronchodilator positive response in FEV1 and sputum production, compared to COPD-S patients. For other examined parameters, there were no statistically significant differences between two groups. Conclusion: This is the first study evaluating and shown some differences in the clinical and para-clinical characteristics of COPD-B patients (long exposure to wood smoke raised by baking bread; > 100 hour-years, for at least ten years) and COPD-S patients (> 10 pack-years of exposure to tobacco smoke).

Keywords:

Baking bread , Biomass , Chronic Obstructive Pulmonary Disease (COPD) , Tobacco smoking , Wood smoke.