ABSTRACT
BACKGROUND: It has been recognized that cessation of treatment with inhaled corticosteroids evokes a recurrence of symptoms in most asthmatics within a month. OBJECTIVE: To examine whether a useful model of asthma for studies on effects of new antiasthmatic drugs can be induced by discontinuation of inhaled corticosteroids treatment. METHOD: Twenty five patients with controlled asthma on inhaled corticosteroids were enrolled in this study. Spirometric measurements were performed before and 2 weeks after cessation of treatment with inhaled budesonide. Peak expiratory flow rates(PEFR), asthma symptom scores, and short-acting inhaled beta2 agonist requirements were checked during 2-week period before and during 2-week period after the cessation of inhaled budesonide. RESULTS: Discontinuation of treatment with inhaled budesonide resulted in significant falls in FEV1, and morning and evening PEFRs, and significant increase in diurnal variability of PEFR (40% of patients showed diurnal variability of > or = 20%). Their symptom scores and the days required for salbutamol use were also significantly increased. However, the mean fall in FEV1 was 6.9% and the maximum fall 29%, and a significant fall (> or =15%) occurred in only 29% of patients. CONCLUSION: These findings demonstrate that asthma exacerbation can be safely induced by discontinuation of treatment with inhaled corticosteroids in controlled asthmatics, suggesting that this experimental model of mild asthma exacerbation can be used for studying the effects of new antiasthmatic drugs.
Subject(s)
Humans , Adrenal Cortex Hormones , Albuterol , Anti-Asthmatic Agents , Asthma , Budesonide , Models, Theoretical , Peak Expiratory Flow Rate , Recurrence , Withholding TreatmentABSTRACT
BACKGROUND: Researches on the characteristics of fatality-prone asthmatics have been performed in western countries, but there are few reports in this field in Korea. The purposes of this study were to clarify the magnitude of the problem and to identify the risk factors of near-fatal asthma(NFA). METHODS: The records of patients admitted due to asthma attack were analyzed retrospectively. RESULTS: 1) The subjects had NFA in 50.6% and PaCO2 > 45mmHg in 22.9%. Five(11.1%) among NFA patients and 3 out of 19(15.8%) subjects with PaCO2 > 45mmHg required mechanical ventilation. 2) There were no significant differences between NFA and non-NFA in age, sex, resident place, academic career, familial and personal history of atopic diseases, serum total IgE level, positive skin prick test to house dust mites, accompanying allergic rhinitis and aspirin intolerance, emphysema on chest high resolution computerized tomogram, dyspnea perception, previous asthma education, regular OPD follow-up, and use of antiinflammatory drugs. 3) However, cigarette smoking(62.2% vs 38.6%), accompanying paranasal sinusitis(66.7% vs 45.3%), chronic asthma severity(severe persistent: 55.5% vs 29.5%), hospitalization frequency(2.93 vs 1.58), and duration of recent asthma exacerbation(6.6 vs 18.8 days) in NFA were significantly different from those in non-NFA.4) The relative risk for NFA was high in patients with history of hospitalization > 3, severe persistent asthma, exacerbation period < 3 days, smoking, or sinusitis in the order of frequency. CONCLUSION: Near-fatal asthma is a prevalent problem in clinical practice and asthma admission history, severe persistent asthma, short exacerbation period < 3 days, smoking, and paranasal sinusitis are the risk factors warning near-fatal asthma attack in advance.