The effect of inhaled albuterol in moderate to severe asthma

Some recent clinical investigations suggest that regular use of inhaled bronchodilators may lead to deterioration in asthma control.

The purpose of this study was to evaluate the effect of albuterol dosing schedule on clinical outcome in subjects with moderate to severe stable asthma.

Seventeen adults were randomized to two 15-week treatment periods in a double-blind crossover design. Throughout the study, subjects were instructed to take two inhalations four times daily from an unlabeled "test" canister. In the four times daily and as-needed (QID + PRN) period, this canister contained albuterol; in the as-needed (PRN) period, it contained placebo. A "rescue" albuterol canister was available for as-needed use at all times. Inhaler actuations from both the test and rescue canisters were electronically recorded. Outcome measures included prednisone requirements, morning and evening symptoms and peak expiratory flow rates, total and nighttime rescue albuterol use, and asthma-specific quality of life.

The two treatment periods did not differ in symptoms, nighttime albuterol use, or asthma quality of life. During the QID+PRN period both morning and evening peak expiratory flow rates were significantly higher (p < 0.01 and 0.001, respectively) and total rescue use of albuterol was significantly less (p < 0.05) than the PRN period. Days on prednisone tended to be lower in the regular dosing period (p = 0.08).

In our sample of patients with moderate to severe asthma, four times daily dosing of albuterol did not lead to deterioration of asthma control.