Persistent cough is a common and often distressing symptom, and represents one of the most frequent problems for which people seek medical care. While lung problems often underlie a persistent cough, abnormalities in other organs also commonly cause this symptom. Companion symptoms, medical history, physical examination and diagnostic testing are important factors that contribute to an accurate diagnosis and effective treatment plan for persistent cough.
Cough Variant Asthma
Cough variant asthma is a distinct form of asthma in which chronic cough is the lone symptom. The disorder is considered a form of asthma because the airways demonstrate exaggerated sensitivity and the condition improves with bronchodilator medications, two features that occur with all forms of asthma. In a 2009 research study published in the journal "Cough," Dr. Hisako Matsumoto and colleagues note that cough variant asthma is a common cause of chronic cough. Among people with cough variant asthma, exaggerated airway sensitivity causes coughing rather than wheezing, which occurs with classic asthma.
Chronic Bronchitis
Chronic bronchitis, also known as chronic obstructive bronchitis, is a chronic lung condition wherein long-standing irritation of the airways leads to markedly increased mucus production and chronic cough. The National Heart, Lung and Blood Institute reports that airway irritation from cigarette smoke is the leading cause of chronic bronchitis. Because of the strong correlation between smoking and chronic bronchitis, the disorder is commonly known as "smoker’s cough."
Chronic Sinusitis
Chronic sinusitis is an inflammation of the sinuses persisting for eight weeks or more, notes the Cleveland Clinic. Chronic cough is a characteristic symptom of this disorder. The cough is typically most troublesome upon awakening and at night. Post-nasal drip, the drainage of nasal mucus down the back of the throat, activates the cough reflex. Other symptoms of chronic sinusitis that point to this condition as the cause of chronic cough include facial pain or pressure, decreased sense of smell, ear fullness or pressure and headache.
Gastroesophageal Reflux Disease
Gastroesophageal reflux disease is a condition wherein the back flow of stomach contents and acid causes irritation of the esophagus--the muscular tube through which food flows from the mouth to the stomach. Irritation of the esophagus can cause chronic cough due to nerve stimulation of the airways termed the esophageal-bronchial reflex. In a 2006 American College of Chest Physicians practice guideline published in the journal "Chest," Dr. Richard Irwin notes that gastroesophageal reflux disease is one of the most frequent causes of chronic cough. Irwin further states that up to 75 percent of people with chronic cough due to gastroesophageal reflux disease have no gastrointestinal symptoms of the disorder.
References
- "Cough"; Features of Cough Variant Asthma and Classic Asthma During Methacholine-Induced Brochoconstriction: A Cross-Sectional Study; Hisako Matsumoto, M.D., et al.; March 2009
- National Heart, Lung and Blood Institute: COPD
- Cleveland Clinic: Sinusitis
- "Chest"; Chronic Cough Due to Gastroesophageal Reflux Disease, ACCP Evidence-Based Clinical Practice Guidelines; Richard S. Irwin, M.D.; January 2006
- MayoClinic.com: Chronic Cough
