Effects of long-term use of inhaled steroids (beclomethasone dipropionate) in patients with occupational asthma no longer exposed

Ten subjects with occupational asthma who, were either no longer exposed or had minimal exposure, were controlled every three months after cessation of exposure. All subjects showed airway responsiveness to metacholine, complained of mild symptoms and had minor lung function abnormalities. The subjects underwent inhalation therapy with beclomethasone dipropionate (2000 micrograms/day) for 3 to 12 months. Although pulmonary function values and symptoms did not change significantly during treatment, PD20 FEV1 improved markedly after 3 months and further improved after the longest period of treatment. PD20 FEV1 after treatment was significantly correlated with the base PD20 FEV1 value and not with the FEV1 increase. Good therapeutic results were obtained in 6 subjects. In the remaining 4 subjects who did not respond to treatment, the base PD20 FEV1 value was below 200 micrograms. In 4 of the 6 subjects who responded to treatment PD20 FEV1 was lower than during treatment but higher than before treatment.