Low- and high-dose fluticasone propionate in asthma; effects during and after treatment.
The dose dependency of the effects of inhaled corticosteroids on markers of asthmatic airway inflammation have not been well studied. There is a need to study the dose/response effects on this inflammation. In order to determine the dose/response effects of fluticasone propionate (FP), 24 asthmatic subjects were randomized to low- (100 microg x day(-1)) or high-dose (1,000 microg x day(-1)) FP for six weeks followed by placebo for 3 weeks. During treatment, the median increase in forced expiratory volume in one second (FEV1)was 12% in the high-dose group (p<0.05) and 10% in the low-dose group (p<0.05) (p>0.05 between groups); the median decrease in the percentage of sputum eosinophils was 93% in the high-dose group (p<0.05) and 46% in the low-dose group (p<0.05) (p>0.05 between groups). Symptoms, salbutamol use, morning peak flow, provocative concentration of methacholine causing a 20% fall in FEV1 (PC20), sputum eosinophil cationic protein concentration and tryptase activity improved significantly in both groups (p<0.05), but only the improvement in salbutamol use was greater in the high-dose group (p<0.05). During the run-out, the improvements in FEV1 and PC20 were rapidly reversed in both groups, but the improvements in peak flow and tryptase activity persisted; the improvement in sputum eosinophil concentration persisted only in the high-dose group (p<0.05). It was concluded that dose/response effects for FP are not easily demonstrable because low-dose FP is quite effective. For most outcomes, the effects of high- and low-dose FP are relatively short-lived after treatment is stopped. This finding raises questions about the extent to which inhaled corticosteroids are disease-modifying in asthma.
Gershman
N H
NH
Dept of Medicine, University of California, San Francisco 94143, USA.
Wong
H H
HH
Liu
J T
JT
Fahy
J V
JV
D000280:Administration, Inhalation; D000287:Administration, Topical; D000328:Adult; D000420:Albuterol / Q000008:administration & dosage / Q000009:adverse effects; D000730:Androstadienes / Q000008:administration & dosage* / Q000009:adverse effects; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage* / Q000009:adverse effects; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D000068298:Fluticasone; D005541:Forced Expiratory Volume / Q000187:drug effects; D005938:Glucocorticoids; D006801:Humans; D008297:Male; D008875:Middle Aged
D000730:Androstadienes; D018927:Anti-Asthmatic Agents; D000893:Anti-Inflammatory Agents; D005938:Glucocorticoids; D000068298:Fluticasone; D000420:Albuterol