Chronic Cough: Identifying the Cause is the Key to the Cure
When someone sneezes we usually say, "Bless you," but when you hear a bellowing cough your instincts are to run away. The suffering cougher goes unblessed and often feels isolated as people flee for cover hoping not to inhale any aerosolized infectious particles. Such defense mechanisms are not looked down upon in today's era of germ avoidance, but what defense does the cougher have against the seemingly never-ending cough?
The role and effectiveness of cough suppressants will be a topic to revisit on another day. More importantly is identifying the cause of prolonged coughing. Let's first discuss the difference between acute and chronic cough.
An acute cough generally goes away within three to four weeks for a child, and within eight weeks for an adult. There are many causes of acute cough, but the most common one is the common cold. Other causes include sinus infections, flu syndrome, other upper respiratory infections, and ear infections. Many acute coughs don't make it to the doctor's office because they go away by the time the decision is made to make an appointment.
Chronic cough lasts for several weeks and more often requires a visit to the doctor. The disruptive potential of persistent coughing can only be appreciated by those who have experienced it. Severe cough can be associated with vomiting, headache, fatigue, sore throat, gasping, difficulty breathing, chest pain, rib fracture, dizziness, and incontinence (accidental loss of urine or stool). Loss of sleep (for family as well as the cougher), missed days of school or work, and decreased productivity (at school or work) also are common factors.
Causes of chronic cough
A cough lasting for more than a month should be evaluated. The majority (80-90%) of chronic coughs fall under one or more of the following categories, once you exclude tobacco-related cough:
2)**** Chronic sinusitis
(The remaining 10-20 percent includes cancer, tuberculosis, sarcoidosis, heart disease and other causes.)
I've seen patients who have been coughing for years despite treatment with several short courses of antibiotics for sinus infection. Thorough evaluation of some of them led to identifying two or more of the above causes simultaneously contributing to their cough. They required treatment for multiple problems in order to resolve their coughing.
For example, one 40-year-old woman was referred to my office for consultation because of six months of persistent cough. Three courses of antibiotics prescribed by her primary doctor had improved, but not eliminated, coughing. The improvement would only last as long as she was on the antibiotic. She claimed her cough was worse in the fall, especially when she was in her outdoor garden.
Allergy skin testing revealed she was allergic to ragweed (a fall seasonal allergy trigger) and dust mite (a year-round indoor trigger). Pulmonary function testing identified some reversible lung obstruction (a characteristic of asthma). A CAT scan of her sinuses showed chronic changes suggestive of sinusitis. Once I treated her for allergic rhinitis, asthma and sinusitis, her cough went away. Cases like hers are referred to me several times over the course of a year.
Here are five tips on how to assist your doctor in evaluating prolonged cough:
- Jot down a few notes about when the cough began and other symptoms associated with it (fever, chills, sweats, nausea, vomiting, or weight loss).
2)** **List all the medications, prescribed and over-the-counter, that have been taken before and since the cough began. Some medications for blood pressure have been associated with chronic cough (angiotensin converting enzyme inhibitors [ACE]).
3)** **Write down what makes the cough better or worse, and whether it improves or worsens with changes in body position, exercise or with daytime versus nighttime hours.
Find out if you need to restrict any of the medications you are taking leading up to the appointment. You may need to hold off on antihistamines for skin testing, or hold off on your reliever inhaler on the morning of the appointment (for pulmonary function testing).
Have your list of questions ready for the doctor and place the most important ones at the top.
In most cases, chronic cough can be successfully treated, but it takes a joint effort between the doctor and patient to figure it out. Once the cause or causes are identified, effective treatment can be started.
Thompson, J.A., Uncovering Clues to Chronic Cough. Advance: for Managers of Respiratory Care, October 2000, Vol. 9, No. 9, pp. 34-37