Chronic Cough? Consider Asthma

As the winter weather sets in and cold viruses circulate, we see lots of kids with cough-variant asthma in the clinic.  As opposed to the turn-blue-and-fall-over-wheezing drama that many people in my generation associate with asthma attacks, most kids with asthma just cough.  And cough and cough and cough…and cough.  The cough is typically triggered by a viral respiratory infection or allergy; the cold or allergy causes nasal congestion, runny nose, and sore throat.  But while the other kids with the same bug improve after a week or two, a child with asthma just keeps on coughing.

One clue that your child’s cough may be asthma-induced is a family history of hayfever or eczema.  These conditions tend to run together in families.  Another clue is the chronicity and intensity of the cough; it starts with a normal cold virus, but is much worse in intensity and duration than everybody else suffering from the same cold.  The cough can be dry or loose, and is typically worse at night and with exercise.  You may notice that your child cannot take a deep breath without coughing.  She may complain of shortness of breath, chest “tightness”, or an air-hunger sensation.  The cough may be accompanied by wheezing, rapid breathing, or labored breathing.  But more often it’s just a cough.

Standard treatment for asthma-induced cough is with inhaled medicines that can be delivered by inhaler or nebulizer.  One medicine provides immediate relief of symptoms, so it is called a “quick relief” medicine.  Albuterol is the most common; some brand names are ProAir, Ventolin, Proventil or Xopenex.  Other medications, called “controllers“, are given as a daily preventative to reduce inflammation, so the quick-relief meds can work properly.  Some common  examples include Flovent, Pulmicort, Singulair, budesonide, Advair, and Qvar.  Controller medications DON’T help symptoms immediately.  They typically require several days of consistent use to begin working.

As pictured above, asthma causes two problems in the air tubes of the lungs.  First, it causes contraction of the muscles that surround each air tube.  This narrows the tube, making breathing more difficult.  Quick-relief medications relax these tightened muscles, allowing the tube to widen for greater air flow.  The second problem is swelling and inflammation of the walls of the air tube.  This narrows the tube further, making breathing even more difficult.  Sometimes the airway inflammation is so bad that relaxing the constricted muscles with quick-relief medications doesn’t allow the tube to widen; there’s just too much swelling.  This is why quick-relief medications, such as albuterol, sometimes don’t seem to work as well.  Controller medications act to reduce the inflammation; both work together to open the airways and keep them open.

A typical regimen for treating cough-variant asthma may be:  quick-relief medication 3-4 times per day while a child has a cold and cough (a week or so), and controller medication once daily throughout the winter season, whether the child has a cough or not.  The controller keeps inflammation down between triggers (usually viral colds), so when your child catches the next cold virus it is much less likely to trigger the constriction and inflammation, therefore much less likely to trigger the asthma cough. 

Triggers for asthma-related cough are different for each asthmatic.  Most kids’ symptoms are triggered by cold viruses, which typically hit kids every 2-3 weeks during our long winter months.  Some kids have allergic triggers, such as pet dander or pollen.  Cold air and exercise are other common triggers.   Cigarette smoke and air pollution are universal triggers.  Over time a parent learns to recognize their child’s triggers; some can be prevented through avoidance.  For exercise-induced asthma, pre-treating with a quick-relief medication can prevent exhertional symptoms.

To diagnose asthma, we get a thorough history regarding the cough, triggers, and a detailed family history.  Sometimes the physical exam of a child with cough-variant asthma is completely normal.  Sometimes his/her oxygen level is a bit low, or sometimes the breath sounds are a bit diminished.  Typically the best way to diagnose asthma after the history and physical exam is to begin treatment and see if it helps. If it does, we have our diagnosis.

We may recommend “spirometry” testing for older children.  Spirometry tests the force and flow of air during a forced exhalation, and can provide another piece to the puzzle.  X-rays don’t typically help us diagnose asthma.  In fact, an asthmatic lung on X-ray frequently looks like pneumonia.  When children with cough-variant asthma seek care from urgent cares or emergency departments, they are frequently misdiagnosed with pneumonia.

Asthma is so much more common than we once thought.  And, it’s not the debilitating condition we once thought it was.  Asthma treatment may take some work and organization, but a child with well-treated asthma should be able to do anything he wants to do, cough-free.