Exhaled and Systemic Biomarkers to Aid the Diagnosis of Bronchial Asthma in Elite Water Sports Athletes

ABSTRACT Purpose Our aim was to evaluate the accuracy of a combined airway inflammatory biomarker assessment in diagnosing asthma in elite water sports athletes. Methods Members of the Hungarian Olympic and Junior Swim Team and elite athletes from other aquatic disciplines were assessed for asthma by objective lung function measurements, and blood eosinophil count (BEC), serum total IgE, FENO measurements, and skin prick testing were performed. A scoring system from BEC, FENO, serum IgE, and skin test positivity was constructed by dichotomising the variables and assigning a score of 1 if the variable is elevated. These scores were summed to produce a final composite score ranging from 0 to 4. Results A total of 48 participants were enrolled (age 21 ± 4 years, 42% male), of which 22 were diagnosed with asthma. Serum total IgE and FENO levels were higher in asthmatic individuals (68 [27-176] vs. 24 ([1-44], p = 0.01; 20 [17-26] vs. 15 [11-22], p = 0.02), and positive prick test was also more frequent (55% vs. 8%, p < 0.01). Asthmatic participants had higher composite variable scores (2 ([1-3] vs. 1 [0-1], p = 0.02). ROC analysis showed that total IgE, FENO, and the composite variable were suitable for identifying asthmatic participants (AUC 0.72, p = 0.01; 0.70, p = 0.02, and 0.69, p = 0.03). A composite score of >2 reached a specificity of 96.2%, sensitivity of 36.4%, and likelihood ratio of 9.5. Logistic regression model revealed a strong association between the composite variable and the asthma diagnosis (OR 2.71 (95% CI 1.17-6.23), p = 0.02). Conclusions Our data highlight the diagnostic value of combined assessment of Th2-type inflammation in elite water sports athletes. The proposed scoring system may be helpful in ruling in asthma in this population upon clinical suspicion.