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5.21.4.2: Risk Factors/Protective Factors
Opening the book…
The primary risk factor for COPD is cigarette smoking. Most people who develop COPD are current or former smokers (National Heart, Lung, and Blood Institute, 2023). However, a rare genetic condition called Alpha-1 antitrypsin (AAT) deficiency can cause asthma and COPD, and is a cause of about 5% of COPD cases (Brode et al., 2012). Other environmental or occupational exposures to secondhand smoke, air pollution, chemical fumes, or smoke from cooking can all damage the lungs. Most people who develop COPD are over the age of 40 (National Heart, Lung, and Blood Institute, 2023a).