The Use of Home Spirometry in the Monitoring of Patients With Acute Exacerbation of Asthma

After outpatient clinic visit, asthmatic patients with worsening of symptoms (including dyspnea, wheezing, chest tightness, cough, activity limitation, awaken in the midnight due to discomfort) and are diagnosed of acute exacerbation by physician, will be recruited. The patients are asked to record symptoms using asthma symptom diary (ASD) with home spirometry simultaneously for 14 days. Visit 1 (day 1) All patients will be evaluated the following: Record the patients' demographics (age, gender, race), baseline characteristics, comorbidities, health care resources use (visits, lab tests, hospitalization and cost), pharmacological and non-pharmacological treatments Blood sampling for eosinophils, eosinophil cationic protein (ECP) and immunoglobulin E (IgE) as clinically indicated (if no data available within one year for the last two) The study assistant will introduce to the patient how to manipulate the home spirometry and its app, and to record the daily asthma symptoms by using the ASD on the mobile phone. Visit 2 (day 15) All patients will be arranged outpatient clinic follow up 2 weeks later from the first visit. The outpatient clinic physician will check the home spirometry report and ASD symptom score in the past 2 weeks, and have a well explanation of these results. Statistical analysis The usage of digital function including input ASD, and the lung function from portable spirometer in study arm will be demonstrated by descriptive statistics.

To compare between changes in asthma symptoms by asthma symptom diary (scoring in points) and changes in forced expiratory volume in 1 second (FEV1, in liters) in patients with acute exacerbation of asthma. Asthma symptom diary (ASD) consist of daytime and nighttime score will be recorded everyday over the 14-day study period.

To compare the changes in daily asthma rescue medication use and pulmonary function by home spirometry

To compare between changes in the daily inhalation times (puffs in times per day) and changes in forced expiratory volume in 1 second (FEV1, in liters) in patients with acute exacerbation of asthma. Rescue medication (Fenoterol, Albuterol, inhaled corticosteroid-formoterol) use was measured by the number of inhalations per day.

To compare between changes in asthma symptoms (scoring in points) and forced expiratory volume in 1 second (FEV1, in liters) in patients with acute exacerbation of asthma in different asthma phenotypes (allergic type, non-allergic T2 type, non-T2 type).

Inclusion Criteria: Age 20 to 75 years old asthmatic patients under regular treatment for at least 3 months. Patients in asthma acute exacerbation (symptoms onset within 1 week) and received oral corticosteroid for more than 3 days. Exclusion Criteria: Refuse to provide inform consent. Patients with chronic obstructive pulmonary disease. Patients who receive more than 20mg prednisone or equivalent dose per day. Patients who are incapable of using smart phone.

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