The differences of clinical profiles by house dust mite sensitization in patients with asthmatics in Soonchunhyang University Hospital cohort

PURPOSE: The majority of patients with allergic disease are highly sensitized to house dust mites (HDM). There is few data to observe sensitization rate to HDM in asthmatics in Korea. The aim of this study was to observe the differences of clinical profiles by HDM sensitization in patients with asthmatics in Soonchunhyang University Hospital (SCH) cohort. METHODS: We recruited 2,345 asthmatic patients in SCH cohort. Lung function, body mass index and sputum and blood eosinophils, and PC20, and clinical profiles were compared by HDM sensitization. RESULTS: Dermatophagoides farinae (Derf) and/or Dermatophagoides pteronyssinus (Derp) (+) sensitization rate was higher prevalence in male than in female. Compared with nonatopy asthmatics, Derf and/or Derp (+) asthmatics had early onset of age [Derf and/or Derp (+) vs. Derf and Derp (-) vs. atopy (-); 32.5+/-0.51 vs. 36.1+/-0.88 vs. 43.1+/-0.54, P<0.05]. Derf and/or Derp (+) asthmatics had shorter duration of asthma symptom than that of nonatopy asthmatics. Derf and/or Derp (+) asthmatics had lower forced expiratory volume in one second and forced vital capacity than those of Derf and Derp (-) asthmatics. PC20 in Derf and/or Derp (+) asthmatics had lower than those of Derf and Derp (-) and nonatopy asthmatics [Derf and/or Derp (+) vs. Derf and Derp (-) vs. atopy (-); 5.4+/-0.24 mg/mL vs. 6.59+/-0.52 mg/mL vs. 7.19+/-0.33 mg/mL, P<0.05]. Blood eosinophils number in Derf and/or Derp (+) asthmatics had higher than that of nonatopy asthmatics (414.7+/-131.1 vs. 350.6+/-14.0, P<0.05). Total immunoglobulin E (IgE) in Derf and/or Derp positive asthmatics had higher than that of Derf and Derp negative and nonatopy asthmatics. There was no difference of body mass index among three groups. CONCLUSIONS: Our data indicate that atopy asthmatics sensitized to Derf and/or Derp had early onset of age, high total IgE and airway responsiveness, and eosinophilic inflammation.

Airway Responses to Deep Inspiration in Asthma by Different Bronchial Challenge

OBJECTIVE: Deep inspirations (DI) provide physiologic protection against airway narrowing and DI-induced bronchoprotection and bronchodilation are impaired in asthma. METHODS: To evaluate effect of DI on airway narrowing during methacholine challenge, we compared the 2 minutes tidal breathing method and the breath dosimeter method. Methacholine challenge in 12 asthmatics and 10 healthy controls was cross-overly performed by two methods. On first visit, a questionnaire for symptoms, allergy skin test, spirometry, and methacholine challenge was performed. On second visit, spirometry and methacholine challenge using the 25 mg/mL at 5 minutes intervals during the 2 minutes tidal breathing method and the ten-breath dosimeter method were performed on two separate days at same time each day. RESULTS: The decreases in forced expiratory volume in one second (FEV1) and forced vital capacity during the 2 minutes tidal breathing method and dosimeter method in patients with asthmatics were higher than those in normal controls. The decreases in FEV1 and forced vital capacity during the 2 minutes tidal breathing method were higher than during dosimeter method in both asthmatics and controls. CONCLUSION: These observations indicate that the continuous generation method produce more bronchoconstriction than the dosimeter method during methacholine challenge and asthmatics had more bronchoconstriction than controls, suggesting inhibition of DI enhance methacholine induced airway narrowing in asthmatics.