Patients with severe asthma related to sensitization to Aspergillus fumigatus show significant improvement of symptoms and inflammatory parameters when exposed to a high-altitude environment, according to research presented here at the American Thoracic Society (ATS) 2011 International Conference.
Encouraged that a uniquely dry climate at high altitudes can offer an environment that is nearly free of A fumigatus spores, a group of Dutch researchers hypothesized that the setting may benefit patients who are sensitive to the spores.
To test the hypothesis, they recruited 170 patients (113 female), aged 13 to 81 years, who had severe asthma that was uncontrolled at sea level in Holland. They were classified for sensitization for A fumigatus and then enrolled in a multidisciplinary, 12-week treatment program at the Dutch Asthma Centre Davos, in Switzerland.
“The Dutch Asthma Centre Davos is situated at 1600 meters (about 5250 feet) altitude, and the climate there is very dry and there is very little air pollution, so this was an ideal setting to study patients with severe asthma who have A fumagatus sensitivity,” said lead study author Lucia H. Rijssenbeek-Nouwens, MD, of the Dutch Asthma Centre Davos.
At the end of the 12-week treatment, patients who were and who were not sensitized to A fumigatus showed significant improvement in all parameters, including the Juniper asthma control questionnaire (Juniper ACQ), Juniper asthma-related quality of life questionnaire (Juniper AQLQ), postbronchodilator forced expiratory volume that was 1% of predicted, postbronchodilator residual volume/total lung capacity percentage predicted, fractional exhaled nitric oxide (FeNO), and daily dose of oral corticosteroids, related to changes in total IgE.
Patients in the A fumigatus–associated asthma group, however, showed more significant improvement in FeNO, total IgE, and total eosinophils.
Their changes from baseline in total IgE are correlated with changes in Juniper ACQ (r = 0.31, P = .35), Juniper AQLQ (r = −0.734, P = .01), and FeNO (r = 0.298, P = .04).
“After 12 weeks of treatment at the Davos center in Switzerland, we saw significant clinical improvement in both groups in terms of asthma control, quality of life, and lung function,” Dr. Rijssenbeek-Nouwens said.
“In the group with A fumigatus, we saw an even more important decline in the FeNO and blood eosinophils and the total IgE, and the decrease in total IgE correlated with improvement in asthma control and decreases in FeNO and eosinophils,” she noted.
Treatment of asthma patients with A fumigatus sensitivities can be a significant challenge, but the study demonstrates the potential relief that patients can find at higher altitudes, explained Anneke ten Brinke, MD, PhD, a chest physician with the Medical Centre Leeuwarden, in Leeuwarden, the Netherlands.
“Patients with severe asthma form a difficult-to-treat group of patients and a real challenge to doctors working in this field,” said Dr. Brinke, who moderated the poster session. Dr. Brinke was not associated with the study.
“In particular, patients with a sensitivity to Aspergillus seem to be at great risk for more severe disease, as has been shown in some previous studies.
“In this poster, Dr. Rijssenbeek-Nouwens compares severe asthma patients referred to their high-altitude hospital in Davos with and without this sensitization to Aspergillus, and although the study has some limitations, she clearly shows that even those severe patients with sensitization to Aspergillus do profit from a treatment at high altitude, probably due to the fact that the dry climate at high altitude is almost free of this fungus,” Dr. Brinke observed.