Chest
Clinical Investigations: COPDIdentification of Smokers Susceptible to Development of Chronic Airflow Limitation: A 13-Year Follow-up
Section snippets
Materials and Methods
We have examined 56 former steelworkers, now retired, all men, aged 62.5±2.7 years (mean±SD), at the end of a 13-year follow-up study. Briefly, at the start of the study, we investigated a homogeneous group of 104 “blue collar” active workers from a steel plant near Brussels (Belgium), 50 years old on the average. All of them were long-term smokers (31.7± 14.3 pack-years). Selection criteria included an age between 45 and 55 years and at least 10 years of service in the same company. Workers
Results
Table 1 (right) presents the anthropometric and the functional data, as well as the smoking history (expressed as pack-years) for the whole group of 56 subjects studied after 13 years. At the end of follow-up, there were 21 former smokers (35±13 pack-years) and 35 current smokers (45±20 pack-years). There was no change in either average height or weight over time. FEV1/VC ratio was 63.1 ±11.3% in current smokers and 66.8± 11.3% in former smokers (p>0.05). The corresponding FEV1 values were
Discussion
Cigarette smoking is recognized as the cardinal cause of COPD, but only a relatively small percentage of smokers are developing clinically overt disease.23 How to identify these high-risk smokers is still considered an elusive task. Present results show that a subset of smokers characterized by a low FEV1/VC ratio (or low FEV1 and a high N2 slope are probably the high-risk subjects. Indeed, after 13 years, they reached a functional profile observed in the advanced stages of COPD.
At the end of
Acknowledgments
The authors thank Constant Pahulycz, MA, for technical assistance with the manuscript, and Professors B. Nemery and K.P. Van de Woestijne for critical reading of the manuscript and fruitful suggestions.
References (37)
- et al.
Early detection of obstructive lung disease by analysis of maximal expiratory flow-volume curves
Chest
(1973) - et al.
Resistance of central and peripheral airways measured by a retrograde catheter
J Appl Physiol
(1967) - et al.
Site and nature of airway obstruction in chronic obstructive lung disease
N Engl J Med
(1968) - et al.
Frequency dependence of compliance as a test for obstruction in small airways
J Clin Invest
(1969) - et al.
Quantitative analysis of the alveolar plateau in the diagnosis of early airway obstruction
Am Rev Respir Dis
(1973) - et al.
Closing volume in 50 and 60 year-old-men (a preliminary report)
Scand J Respir Dis
(1974) - et al.
The relations between structural changes in small airways and pulmonary function tests
N Engl J Med
(1978) - et al.
Correlation between the function and structure of the lung in smokers
Am Rev Respir Dis
(1979) - et al.
Small airway pathology is related to increased closing capacity and abnormal slope of phase III in excised human lungs
Am Rev Respir Dis
(1980) - et al.
Small airway disease: an assessment of the tests of peripheral airway function
Am J Med
(1974)
A lung function changes in smokers with normal conventional spirometry
Am Rev Respir Dis
Ability of spirometry, flow-volume curves and the nitrogen closing volume test to detect smokers: a population study
Scand J Respir Dis
Simplified diagnosis of small airway obstruction
N Engl J Med
Relative sensitivity of maximal expiratory flow-volume curves using spirometer versus body plethysmograph to detect mild airway obstruction
Am Rev Respir Dis
Development of impaired lung function: natural history and risk factors
The single breath N2-test predicts the rate of decline in FEV1.0: the study of men born in 1913 and 1923
Eur J Respir Dis
Risk factors associated with longitudinal change in pulmonary function
Am Rev Respir Dis
Does the single-breath N2-test identify the smoker who will develop chronic airflow limitation?
Am Rev Respir Dis
Cited by (0)
This study was supported by grant 7280-03-020 of the European Coal and Steel Community.