Patients who suffer from an allergy and chronic obstructive pulmonary disease (COPD) are at a higher risk for COPD exacerbation. Allergies also make respiratory symptoms worse for COPD patients.
According to a new study from a team of researchers at Johns Hopkins University in Baltimore, there is a connection between allergic disease and COPD. Allergic reactions occur from inhaling airborne allergens into the nose or lungs. These allergens cause histamines and cell products to be released into the body and cause respiratory symptoms.
Symptoms include runny nose, nasal swelling, sneezing and itchy eyes.
"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," Associate Professor of Medicine at the Johns Hopkins Asthma and Allergy Center Dr. Nadia N. Hansel said.
Among the patients in the NHANES III cohort, 296 COPD patients also suffered from some type of allergy, defined as self-reported or diagnosed by a doctor. The patients who had hay fever or allergy related upper respiratory symptoms were more likely to wheeze, have chronic cough and chronic phlegm. COPD exacerbation risk that requires an acute visit to the doctor was significantly increased.
"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," Hansel said.
Among the second cohort of 77 patients, 23 had an allergy, which was determined by immunoglobulin E testing. Wheezing and awakening at night due to chronic coughing was significantly high among these patients. They were also more likely to require antibiotic treatments or an acute visit to the doctor and have COPD exacerbation.
"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," Hansel said. Findings of the study were published online in the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.
