Asthma morbidity in patients with atopy and a history of wheezing is associated with high urinary dichlorophenol levels which are also associated with greater total serum IgE, according to researchers.
“The present results indicate that atopic wheezers with urinary dichlorophenol levels in the upper tertile are more likely to have physician-diagnosed asthma, to miss days from work or school because of wheezing, to require medications for wheezing, or to have wheezing with exercise,” researchers wrote.
Elina Jerschow, MD, MSc, of the Albert Einstein College of Medicine/Montefiore Medical Center in Bronx, NY, and colleagues collected data from a sample of 2,125 participants aged at least 6 years from the US National Health and Nutrition Examination Survey 2005–2006. They identified a subsample of patients who reported wheezing in the past year (n=250).
The subsample was broken down into the following categories: atopic or nonatopic wheezers with higher 2, 5–dichlorophenol levels who were more frequently diagnosed with asthma by a physician (OR=4.7 for highest vs. the lowest tertile, P<.001), required more prescriptions for asthma medications (OR=2.2, P=.046), and reported more exercise-induced wheezing (OR=5.8, P=.045) vs. atopic wheezers with low dichlorophenol levels, according to data.
Jerschow and colleagues also found that atopic wheezers with greater 2, 5– or 2, 4– levels were more likely to miss work (OR=10, P<.001) or school (OR=11.4, P<.01) because of wheezing.
Conversely, there were no significant associations between dichlorophenol levels and asthma morbidity measurements in nonatopic wheezers, researchers wrote. The 2–dichlorophenol metabolites appeared positively tied to increased serum IgE levels in the larger study sample, according to data.
“Prospective studies are necessary to determine the cause-and-effect relation underlying these associations in wheezers and those with asthma,” researchers concluded.
Disclosure: The researchers report no relevant financial disclosures.