title: Sputum eosinophilia predicts benefit from prednisone in smokers with chronic obstructive bronchitis.
abstract: A reliable predictor of benefit from corticosteroid treatment in patients with chronic airflow limitation is needed. In a single-blind, sequential crossover trial of placebo and prednisone (30 mg/day) treatment, with each given for 2 wk, we investigated whether an increased proportion of sputum eosinophils (>= 3%) predicts a beneficial effect of prednisone in smokers with severe obstructive bronchitis. Patients were seen before and after each treatment. Clinical measurements were made blind to the laboratory findings and vice-versa. Eighteen of 20 patients completed the study. Eight had sputum eosinophilia and similar clinical and physiologic characteristics to those of 10 patients without a finding of sputum eosinophilia. Only in patients with sputum eosinophilia did prednisone, as compared with placebo, produce a statistically significant and clinically important mean effect on effort dyspnea of 0.8 (95% confidence interval [CI]: 0.3 to 1.2), p = 0.008, and in quality of life of 1.96 (95% CI: 0.5 to 3.3), p = 0.01, associated with a small improvement in FEV1 of 0.11 L (95% CI: - 0.04 to 0.23 L), p = 0.05. In these patients, prednisone also produced a significant decline in the median sputum eosinophil percentage, from 9.7% to 0.5% (p = 0.002), eosinophil cationic protein (ECP), from 6, 000 microgram/L to 1,140 microgram/L (p < 0.001), and fibrinogen, from 25. 3 mg/L to 5.4 mg/L (p < 0.001). These findings indicate that in smokers with severe airflow limitation, sputum eosinophilia predicts a beneficial effect of prednisone treatment. Improvement in FEV1, after prednisone treatment in this population, is small, and may not be appreciated in clinical practice.
authors.affiliation: Departments of Medicine and Paediatrics, St. Joseph's Hospital and McMaster University, Hamilton, Ontario, Canada.
authors.forename: E
authors.initials: E
authors.lastname: Pizzichini
authors.forename: M M
authors.initials: MM
authors.lastname: Pizzichini
authors.forename: P
authors.initials: P
authors.lastname: Gibson
authors.forename: K
authors.initials: K
authors.lastname: Parameswaran
authors.forename: G J
authors.initials: GJ
authors.lastname: Gleich
authors.forename: L
authors.initials: L
authors.lastname: Berman
authors.forename: J
authors.initials: J
authors.lastname: Dolovich
authors.forename: F E
authors.initials: FE
authors.lastname: Hargreave
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D001798:Blood Proteins / Q000032:analysis; D001991:Bronchitis / Q000188:drug therapy* / Q000473:pathology; D002908:Chronic Disease; D018592:Cross-Over Studies; D004417:Dyspnea / Q000188:drug therapy; D047091:Eosinophil Granule Proteins; D004802:Eosinophilia / Q000473:pathology*; D005260:Female; D005340:Fibrinogen / Q000032:analysis; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume / Q000187:drug effects; D005544:Forecasting; D005938:Glucocorticoids / Q000627:therapeutic use*; D006801:Humans; D018836:Inflammation Mediators / Q000032:analysis; D008297:Male; D008875:Middle Aged; D010919:Placebos; D011241:Prednisone / Q000627:therapeutic use*; D011788:Quality of Life; D015203:Reproducibility of Results; D012260:Ribonucleases; D016037:Single-Blind Method; D012907:Smoking / Q000009:adverse effects; D013183:Sputum / Q000166:cytology*
chemical_list: D000893:Anti-Inflammatory Agents; D001798:Blood Proteins; D047091:Eosinophil Granule Proteins; D005938:Glucocorticoids; D018836:Inflammation Mediators; D010919:Placebos; D005340:Fibrinogen; D012260:Ribonucleases; D011241:Prednisone