抄録
Inhaled corticosteroid (ICS) therapy is a mainstay of bronchial asthma management. Many clinical studies have indicated that an early start with higher doses of ICS contributes to a better prognosis for asthmatic patients, with improved pulmonary functions, airway hyperresponsiveness and quality of life. The current asthma guidelines suggest that once control is achieved, the dose of ICS should be reduced (stepped down) to the minimal level required to control the disease. The rationale for stepping down the dose includes: 1) minimizing adverse effects, 2) contributing to a precise determination of disease severity and 3) achieving better compliance with the therapeutic regimen. However, a one-time reduction in the ICS dose of over 50% results in a high exacerbation rate (50—78%), and predictive markers for the step-down have not yet been established. Leukotriene receptor antagonist (LTRA) or inhaled long acting β2-stimulant (LABA) have led to successful step-down among patients who require a high dose of ICS to control their condition. When asthma becomes less controllable and thus requires a step-up of therapy, adding LTRA, LABA or theophylline (still a good choice in terms of cost effectiveness) results in better control than doubling the dose of ICS. However, stepwise management is mainly applied to patients with mild to moderate asthma. Severe asthma pathophysiologically differs from mild to moderate asthma and problems in applying stepwise management remain unresolved. Thus, efforts must be targeted towards developing more effective therapeutic strategies with which to manage all types of asthma.
