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Abstract
The forced expiratory volume in 1 sec (FEV1) is the most established outcome measure in chronic obstructive pulmonary disease (COPD). However, changes in FEV1in response to treatment are small in relation to the repeatability of the measurement and there is increasing interest in other measures including markers of lower airway inflammation in induced sputum, assessment of symptoms and health status using visual analogue scores, and questionnaires. Little is known about the repeatability of these measures or the safety of sputum induction in COPD. We have assessed the safety of sputum induction in 61 subjects with moderate and severe COPD who participated in a placebo-controlled cross-over study. The within-subject repeatability of sputum markers of airway inflammation, health status using the chronic respiratory disease questionnaire (CRQ) and symptom visual analogue scores (VAS) were estimated from the data obtained from before and after 2 weeks of treatment with placebo. Sputum induction was performed on 122 occasions and was successful resulting in a cytospin adequate to assess a differential cell count in 95% of inductions. The group mean (![Math Eq]()
) FEV1was 1·09 (0·05)[41·6 (2·9)% predicted] and the mean (![Math Eq]()
) fall in FEV1after sputum induction was 120 ml (6) and % fall 10·9% (0·55%). Seven inductions were stopped due to a fall in FEV1>20% and at a further 13 visits the full sputum induction protocol was not completed due to development of symptoms. The reproducibility of measurements, calculated by the intra-class correlation coefficient, was relatively high for all indices measured (0·4–0·95) with the exception of the proportion of lymphocytes (0·15) and epithelial cells (0·3). The ICC for symptom scores and the CRQ domains ranged between 0·87 and 0·96. In conclusion, sputum induction is safe and the cell and fluid phase mediators repeatable in the investigation of airway inflammation in patients with COPD. VAS symptom scores and the CRQ are reproducible outcome measures in COPD.
) FEV1was 1·09 (0·05)[41·6 (2·9)% predicted] and the mean (
) fall in FEV1after sputum induction was 120 ml (6) and % fall 10·9% (0·55%). Seven inductions were stopped due to a fall in FEV1>20% and at a further 13 visits the full sputum induction protocol was not completed due to development of symptoms. The reproducibility of measurements, calculated by the intra-class correlation coefficient, was relatively high for all indices measured (0·4–0·95) with the exception of the proportion of lymphocytes (0·15) and epithelial cells (0·3). The ICC for symptom scores and the CRQ domains ranged between 0·87 and 0·96. In conclusion, sputum induction is safe and the cell and fluid phase mediators repeatable in the investigation of airway inflammation in patients with COPD. VAS symptom scores and the CRQ are reproducible outcome measures in COPD.Keywords
References
REFERENCES
- Re-assessing the evidence about inhaled cortico-steroids in chronic obstructive pulmonary disease.Thorax. 1999; 54: 3-4
- Differences in interleukin-8 and tumor necrosis factor- α in induced sputum from patients with chronic obstructive pulmonary disease or asthma.Am J Respir Crit Care Med. 1996; 153: 530-534
- Severity of airflow limitation is associated with severity of airway inflammation in smokers.Am J Respir Crit Care. 1998; 158: 1277-1285
- Airways obstruction. Chronic expectoration, and rapid decline of FEV1in smokers are associated with increased levels of sputum neutrophils.Thorax. 1996; 51: 267-271
- The safety and success rate of sputum induction using a low output ultrasonic nebuliser.Respir Med. 1999; 93: 345-348
- Indices of airway inflammation in induced sputum: reproducibility and validity of cell and fluid phase measurements.Am J Respir Crit Care Med. 1996; 154: 808-817
- Sputum in severe exacerbations of asthma; kinetics of inflammatory indices after prednisone treatment.Am J Respir Crit Care Med. 1997; 155: 1501-1508
- Comparison of spontaneous and induced sputum for investigation of airway inflammation in chronic obstructive pulmonary disease.Thorax. 1998; 53: 953-956
- Safety of sputum induction in chronic obstructive pulmonary disease.Eur Respir J. 2000; 15: 1116-1119
- Thorax. 1997; 52: S9
- A measure of quality of life for clinical trials in chronic lung disease.Thorax. 1987; 136: 1285-1298
- Measuring health status in chronic airflow limitation.Eur Respir J. 1988; 1: 560-564
- The St George's Respiratory Questionnaire.Respir Med. 1991; 85: 25-31
- Acute pain management: analgesia, implications and consequences after prospective experience with 6349 surgical patients.Eur J Anaesthesiol. 2000; 17: 566-755
- Sputum eosinophilia and short-term response to prednisolone in chronic obstructive pulmonary disease; a randomized controlled trial.Lancet. 2000; 356: 1480-1485
- The use of induced sputum to investigate airway inflammation.Thorax. 1997; 52: 498-501
- Between-observer repeatability of sputum differential cell counts. Influence of cell viability and squamous cell contamination.Clin Exp Allergy. 1999; 29: 248-252
Article info
Publication history
Accepted:
August 6,
2001
Received:
May 3,
2001
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© 2001 Harcourt Publishers Ltd. Published by Elsevier Inc.
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