There are a variety of irritants that may contribute to or cause chronic bronchitis, including smoking, dust and chemical irritants, air pollution, repeated infections, and a rare hereditary disorder. Allergies can exacerbate existing cases of chronic bronchitis and worsen symptoms.
Cigarette smoking is the leading cause of chronic bronchitis. The inhaled smoke can cause can cause a temporary paralysis of the cilia in the lungs, leading to irritation, swelling, and narrowing of the bronchial tubes. As the disease progresses, breathing becomes more difficult, and the alveoli (the lung’s air sacs) become damaged. Mucous begins to build up, and the lungs are less able to supply oxygen to the rest of the body. Continuing to smoke after being diagnosed with chronic bronchitis can further damage the lungs and lead to even more severe lung damage.
Dust and Chemical Irritants
Certain types of dust as well as chemical irritants are known to increase the risk of developing chronic bronchitis. Miners in particular are at a greater risk, such as gold or coal miners, and workers who are in frequent contact with silica or grain dust. Workers who are exposed to chemicals such as ammonia, chlorine, sulfur dioxide, and other chemicals with strong or irritating fumes are also at risk of developing chronic bronchitis.
Both indoor and outdoor air pollutants (ozone, for example) have been linked to the development of chronic bronchitis.
Repeated Lung Infections
Both viral and bacterial lung infections may, over time, cause damage to the bronchial tubes and lead to breathing difficulties that can ultimately lead to chronic bronchitis.
Alpha-1-antitrypsin is a protease enzyme inhibitor. Those with a hereditary lack of this protease enzyme inhibitor tend to develop both emphysema and chronic bronchitis, both forms of COPD, at a comparatively early age, but the deficiency itself is rare, affecting an estimated 1 in 1,500 and 1 in 3,500 people.
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“Chronic Bronchitis.” Medicinenet.com. N.p., n.d. Web. 28 Oct. 2010. <www.medicinenet.com/chronic
Alpha-1 antitrypsin deficiency – Genetics Home Reference.” Genetics Home Reference – Your guide to understanding genetic conditions. N.p., n.d. Web. 28 Oct. 2010. http://ghr.nlm.nih.gov/condition/alpha-1-antitrypsin-deficiency.