REGULAR VS AS-NEEDED INHALED SALBUTAMOL IN ASTHMA CONTROL

Recent studies have suggested that regular use of inhaled beta, agonis ts cause loss of asthma control as measured by worsening peak-flow rat es, increased asthma symptoms, and more frequent need for supplementar y bronchodilators. However, the magnitude of this effect and the relia bility of investigator-originated definitions of control is unknown. W e studied 341 people with asthma in a four-week, randomised, crossover trial of regular salbutamol (2 puffs-200 mu g-four times daily) for t wo weeks and as needed for two weeks. There were no significant differ ences in morning and evening peak-flow rates between treatments but as thma symptoms and supplementary bronchodilator use were significantly less frequent when salbutamol was given regularly. Asthma episodes occ urred 1.39 (1.52) times per day during regular treatment and 2.44 (1.7 5) times per day during as-needed treatment (p<0.0001) and 0.50 (0.56) vs 0.65 (0.66) times per night (p < 0.0001). Daytime use of supplemen tary salbutamol was 1.14 (1.40) vs 2.35 (1.71) puffs per day, (p <0.00 01); night-time use was 0.45 (0.55) vs 0.64 (0.66) puffs per night (p < 0.0001). When control endpoints were compared between treatment peri ods for each individual by two blinded investigators and control judge d by six different sets of criteria, in 70 asthmatics there was no dif ference in symptom control between periods but in the remainder, contr ol was achieved more often by regular than by as-needed salbutamol (16 6 vs 69, p < 0.0001). In asthma of moderate severity, regularly admini stered salbutamol does not produce lower peak flow rates than as-neede d salbutamol and is associated with less frequent asthma symptoms.