Aaron and colleagues reported that those individuals  who were misdiagnosed with asthma were less likely to have undergone testing for airflow limitation at the time of their initial diagnosis than those whose asthma was confirmed (43.8% vs 55.6%, respectively).4 Such findings highlight the need for a thorough initial evaluation.

“Clinicians should not make a diagnosis of asthma based on symptoms alone,” advised Shawn D. Aaron, MD, professor and division director of respirology at the University of Ottawa in Ontario, Canada, and coauthor of the Canadian asthma misdiagnosis study. “They should confirm the diagnosis with objective testing, ideally by ordering prebronchodilator and postbronchodilator spirometry. If spirometry is normal, they should consider ordering other confirmatory tests such as bronchial provocation tests (methacholine challenge tests or exercise tests) to confirm the diagnosis.”   

Continue Reading

Related Articles

Sleep Disturbances May Provide Clues in ACO  

Sleep disorders may be one of the most overlooked symptoms of ACO.5 In a study that included 25,429 patients (51.7% women; mean age, 54.1 years) from the combined GA2LEN and RHINE Northern European surveys, Mindus and colleagues reported a greater prevalence of sleep disorders in individuals with ACO compared with those with either asthma or COPD. Sleep symptoms in the study included difficulty falling asleep, difficulty staying asleep, early morning awakening, and excessive daytime sleepiness.5 ACO was independently associated with a 2 to 3 times higher probability of having sleep disorders compared with  participants who did not have asthma or COPD, even after adjusting for age, weight, smoking history, education, and sex. The prevalence of self-reported asthma, COPD, and ACO in the study was 6.6%, 1.4%, and 1%, respectively.5  

“This is once again a [study] that shows that patients who have both asthma and COPD [are] an especially vulnerable group,” said Christer Janson, MD, PhD, FERS, professor of respiratory, allergy and sleep research at Uppsala University in Sweden and coauthor of the paper on sleep disorders in ACO. “Sleep has not been studied before and we think our findings are important as sleep has such a large effect on the well-being during daytime.” Dr Janson advises clinicians who manage patients with suspected ACO “to ask about sleep as this is something that is often not done.”

Summary & Clinical Applicability

COPD and adult-onset asthma can present with similar symptoms, but are distinct diseases. Although bronchodilator therapy may be beneficial for both conditions, the recommended use is distinct for each disorder. Patients who are misdiagnosed and treated with the incorrect regimen are at risk for serious adverse effects. Emerging guidelines for diagnosing and treating ACO syndrome will help clinicians manage patients with this newly recognized disorder.

Limitations & Disclosures



  1. Anzueto A, Miravitlles M. Considerations for the correct diagnosis of COPD and its management with bronchodilators [published online March 8, 2018]. Chest. doi:10.1016/j.chest.2018.02.023
  2. Aaron SD, Tan WC, Bourbeau J, et al; for the Canadian Respiratory Research Network. Diagnostic instability and reversals of chronic obstructive pulmonary disease diagnosis in individuals with mild to moderate airflow obstruction. Am J Respir Crit Care Med. 2017;196(3):306-314.
  3. Global Initiative for Chronic Obstructive Lung Disease (GOLD). Asthma, COPD, and Asthma-COPD Overlap Syndrome. http://goldcopd.org/asthma-copd-asthma-copd-overlap-syndrome/. Accessed April 18, 2018.
  4. Aaron SD, Vandemheen KL, FitzGerald JM, et al; for the Canadian Respiratory Research Network. Reevaluation of diagnosis in adults with physician-diagnosed asthma. JAMA. 2017;317(3):269-279.
  5. Mindus S, Malinovschi A, Ekerljung L, et al. Asthma and COPD overlap (ACO) is related to a high burden of sleep disturbance and respiratory symptoms: results from the RHINE and Swedish GA2LEN surveys. PLoS One. 2018;13(4):e0195055.