ATS Publishes Clinical Practice Guidelines on Exercise-Induced Bronchoconstriction

The American Thoracic Society has released new official clinical practice guidelines on the diagnosis and management of exercise-induced bronchoconstriction (EIB), the acute airway narrowing that occurs as a result of exercise.
The guidelines appear in the May 1, 2013 American Journal of Respiratory and Critical Care Medicine.
“While a large proportion of asthma patients experience exercise-induced respiratory symptoms, EIB also occurs frequently in subjects without asthma,” said Jonathan Parsons, MD, associate professor of internal medicine and associate director of The Ohio State University Asthma Center and chair of the committee that drafted the statement. “To provide clinicians with practical guidance for the treatment of EIB, a multidisciplinary panel of stakeholders was convened to review the pathogenesis, diagnosis, and treatment of EIB to develop these evidence-based guidelines.”

The exact prevalence of EIB among asthma patients is not known, but prevalence estimates among subjects without an asthma diagnosis are as high as 20%. Prevalence estimates among athletes are even higher, ranging between 30% and 70% for Olympic and elite-level athletes.

“Given the high prevalence of EIB, evidence-based guidelines for its management are of critical importance,” said Dr. Parsons. “These new guidelines address not only the diagnosis and management of EIB but address other important issues related to EIB, including environmental triggers and special considerations in elite athletes.”

Treatment recommendations in the guidelines include use of a short-acting beta-agonist before exercise in all EIB patients. For those patients who continue to have symptoms after beta-agonist treatment, the guidelines recommend use of a daily inhaled corticosteroid, a daily leukotriene receptor antagonist, or a mast cell stabilizing agent before exercise.

For all patients with EIB, the guidelines recommend that warm-up exercises be performed before planned exercise.

Known environmental triggers for EIB include cold air, dry air, ambient ozone, and airborne particulate matter.  These and other environmental factors may contribute to the increased prevalence of EIB seen among competitive ice skaters, skiers, swimmers, and distance runners. Many of the treatments used to treat EIB, including beta-agonists, are banned or restricted in competitive athletics, as some are considered performance-enhancing, and treatment must be tailored according to the guidelines of the governing bodies of these sports.

“While EIB is common, there are effective treatments and preventive measures, both pharmacological and non-pharmacological,” said Dr. Parsons. “The recommendations in these guidelines synthesize the latest clinical evidence and will help guide the management of EIB in patients with or without asthma and in athletes at all levels of competition.”

Allergic Disease Worsens Respiratory Symptoms and Exacerbations in COPD

Patients with chronic obstructive pulmonary disease (COPD) who also have allergic disease have higher levels of respiratory symptoms and are at higher risk for COPD exacerbations, according to a new study from researchers at Johns Hopkins University in Baltimore.

“Although allergic sensitization and allergen exposure are known to be associated with impairments in lung function, the effects of allergic disease on respiratory symptoms in COPD patients has only recently been studied,” said researcher Nadia N. Hansel, MD, MPH, associate professor of medicine at the Johns Hopkins Asthma & Allergy Center. “Accordingly, we examined the effects of allergic disease on respiratory health in two sets of patients with COPD, one a nationally representative sample of 1,381 COPD patients from the National Health and Nutrition Survey III (NHANES III) and the other a cohort of 77 former smokers with COPD from a study of the effects of endotoxin exposure on health status.”

“We found that COPD patients with an allergic phenotype had an increased risk of lower respiratory symptoms and respiratory exacerbations.”

The findings were published online ahead of print publication in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.

In the NHANES III cohort, 296 COPD patients had an allergic phenotype, which was defined as self-reported doctor-diagnosed hay fever or allergic upper respiratory symptoms. These patients were significantly more likely to wheeze, have chronic cough, and have chronic phlegm and had a significantly increased risk of experiencing a COPD exacerbation that required an acute visit to the doctor.

In the second cohort of 77 COPD patients, the 23 patients with allergic sensitization (determined by immunoglobulin E testing) were significantly more likely to wheeze, to experience nighttime awakening due to cough, and to have COPD exacerbations requiring antibiotic treatment or an acute visit to the doctor.

“Our findings in two independent populations that allergic disease is associated with greater severity of COPD suggest that treatment of active allergic disease or avoidance of allergy triggers may help improve respiratory symptoms in these patients, although causality could not be determined in our cross-sectional study,” said Dr. Hansel.

There were a few limitations to the study, including possible misclassification of COPD in some NHANES patients and the use of self-reported respiratory symptoms and COPD exacerbations.

 “Current COPD guidelines do not address the management of allergic disease in COPD patients,” Dr, Hansel said. “Additional studies of the relationship between allergic disease and COPD are clearly needed.” 

Contact for article: Nadia N. Hansel, MD MPH, Johns Hopkins Asthma & Allergy Center
5501 Hopkins Bayview Circle, Baltimore, MD 21224
Phone: 410 550-2935
Email: nhansel1@jhmi.edu