Do You Really Need Your Asthma Meds?

New study suggests one third of diagnosed adults may not currently have asthma

Woman with asthma inhaler
skynesher/iStockphoto

During the past decade, many health experts have expressed dismay over the rise in the number of medications given to patients to treat various conditions. Medications have adverse effects, and if a person were to take medications that they don’t need, then they put themselves at risk for negative side effects. Moreover, medications cost money and taking excess medication is wasteful and indulgent.

Emerging research suggests that one third of people with physician-diagnosed asthma don’t actually have it. First, many of these people were initially diagnosed without the benefit of objective physiologic testing (i.e., spirometry or pulmonary function tests) and thus were incorrectly diagnosed to begin with. Second, these people may have experienced remission from their asthma.

Asthma Basics

Asthma is a chronic inflammatory airway disease that causes variable degrees of airflow obstruction and bronchial hyper-responsiveness that can be reversed spontaneously or with medications. Of note, the bronchi are passageways in the lungs that branch from the trachea, or windpipe.

During asthma exacerbation, or worsening, the bronchi become hyper-responsive and start to spasm (i.e., bronchospasm). Medications used to treat asthma include inhaled corticosteroids and inhaled beta-agonist bronchodilators.

Common symptoms of asthma include episodes of breathlessness, wheezing, chest tightness and (night-time) cough. Asthma can be triggered by allergies, smoking, exercise, stress and more.

A diagnosis of asthma is based on medical history, clinical exam, pulmonary function testing (i.e., spirometry) and bronchial challenge testing using methylcholine or histamine.

A spirometer is a device used to measure a person’s lung function and lung volumes to figure out how well a person is breathing. Bronchodilator spirometry is a type of spirometry where the clinician first administers a bronchodilator to open the airways (like a beta-agonist) and then looks for an improvement in lung volumes indicative of asthma.

Sometimes spirometry doesn’t support a diagnosis of asthma yet a person is still suspected of having asthma. In these cases, a bronchial challenge test can be performed. With a bronchial challenge test, a specialist administers a bronchoconstrictor, such as methylcholine or histamine, which tightens airways, and looks for evidence of decreased lung function indicative of asthma.   

New Research

Results from a January 2017 longitudinal study published in JAMA suggest that one third of Canadian adults recently diagnosed with asthma don’t in fact have it.

In this study, 613 randomly enlisted participants hailing from 10 of the largest Canadian cities were evaluated between January 2012 and February 2016. The participants were all at least 18 years old and diagnosed with asthma during the past five years. Participants in the study met the following criteria:

  • No smoking history or smoking history fewer than 10 pack years (to exclude participants with chronic obstructive pulmonary disease)
  • No use of long-term prednisone (glucocorticoid) treatment
  • Not pregnant or breastfeeding
  • Able to perform spirometry
  • No heart attack, stroke, or aneurysm within previous three months (contraindications for bronchial challenge testing)

When possible, the researchers obtained diagnostic records from participants’ physicians regarding how these people were originally diagnosed with asthma. In the study, 24 percent of community physicians did not respond to researcher requests for such information.

During a series of visits over several weeks, the researchers used home peak flow meters and symptom monitoring, bronchodilator spirometry, and serial bronchial challenge tests to figure out who didn’t have asthma. Those participants without asthma were then weaned off their asthma medications and re-evaluated during the course of a year. The researchers also sought to establish alternative diagnoses in cases where participants didn’t have asthma.

Ultimately, asthma was ruled out in 203 of 613 participants (33.1 percent). Furthermore, 181 participants (29.5 percent) continued to have no evidence of asthma after an additional 12 months of follow-up. Twelve participants (two percent) didn’t have asthma, but instead had serious cardiorespiratory conditions that were initially misdiagnosed by community physicians. Finally, participants who had a diagnosis of asthma ruled out were less likely to be initially diagnosed using pulmonary function testing and tests of airflow limitation than those in whom asthma was confirmed.

Two notable insights can be gleaned from this study: 

  1. Adults diagnosed with adult-onset asthma may not continue to have asthma or need asthma medications indefinitely.
  2. Per clinical guidelines, more physicians need to use physiologic diagnostic testing, such as bronchodilator spirometry, to properly diagnose asthma in the first place. Simply relying on patient history, physical examination, and clinical acumen is insufficient when diagnosing this condition.

Note that this study had limitations that make it hard to generalize results for everyone with asthma. Specifically, the researchers excluded a number of people with moderate to severe asthma (i.e., those requiring long-term prednisone treatment) and only 45 percent of study participants required daily medication for control of their asthma. Thus, remission among participants with more severe asthma couldn’t be estimated. Instead, the high remission rate observed (33.1 percent) only applies to those originally diagnosed with milder asthma. In fact, other longitudinal studies examining adult asthma remission rates among those with a spectrum of disease severity indicate that remission rates are lower.

Furthermore, because some participants lacked documentation from when they originally were diagnosed with asthma, or were initially diagnosed without the benefit of diagnostic testing, it’s unclear how many participants were improperly diagnosed with asthma in the first place. In other words, some participants who experienced “remission” may never have had asthma in the first place.

What Does All This Mean?

About 75 percent of children with asthma eventually outgrow the condition by adulthood. However, research has shown that remission among those with adult-onset asthma is much lower. The current study, however, suggests that more adults than previously thought may experience remission of milder asthma. These adults may no longer need their asthma medications.

If you or a loved one has been diagnosed with adult-onset asthma, please keep the following in mind:

  • Part of the management of this condition is monitoring. If your symptoms either decrease or remit, you may need either fewer or no asthma medications, respectively. You should monitor your own symptoms and asthma exacerbations (i.e., “asthma attacks”) and share this information with your physician.
  • You should also use a peak flow meter to check how well your asthma is controlled at home. If you find that your asthma is remitting, return to your physician for a re-evaluation. You may not need your asthma medications any more.

Finally, if you’ve been diagnosed with adult-onset asthma, but your physician never used spirometry or other diagnostic testing to confirm a diagnosis, you may want to schedule a visit with a specialist who will perform these tests. One big take away from this study is that physiologic testing is necessary to diagnose asthma—and current guidelines recommend such testing.

Sources

Aaron, SD, et al. Reevaluation of Diagnosis in Adults With Physician-Diagnosed Asthma. JAMA. 2017; 317: 269-279.

Asthma Triggers and Management. American Academy of Asthma, Allergy & Immunology. https://www.aaaai.org/

Hollingsworth, HM and O’Connor GT. Asthma—Here Today, Gone Tomorrow? JAMA. 2017; 317: 262-263.

Usatine RP, Smith MA, Chumley HS, Mayeaux EJ, Jr.. Chapter 55. Asthma. In: Usatine RP, Smith MA, Chumley HS, Mayeaux EJ, Jr.. eds. The Color Atlas of Family Medicine, 2e. New York, NY: McGraw-Hill; 2013.

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