Repeated measures of FEV1 over six to twelve months: what change is abnormal?
J Occup Environ Med 2004 Jun; 46(6):591-595
Monitoring change in FEV1 ([DELTA]FEV1) is useful for assessing adverse respiratory effects in an individual, but high variability impedes reliable recognition of accelerated decline. The American Thoracic Society (ATS) recommends a >=15% year-to-year FEV1 decline for clinical significance. To evaluate the applicability of this criterion in health monitoring programs, we examined the mean, lower 5th percentile, and lower 5% cutoff value of [DELTA]FEV1 determined from 2 tests at 6- and 12-month intervals using data obtained with ATS-recommended equipment and procedures in 389 white male workers, each with 3 to 11 spirometry tests over 5 years. Results indicate that when healthy working males perform spirometry according to ATS standards, a yearly decline in FEV1 greater than 8% or 330 mL should not be considered normal, whereas the 15% ATS criterion could be appropriate in clinical settings.
Respiratory-system-disorders; Coal-miners; Mine-workers; Spirometry; Smoking; Airway-obstruction; Airway-resistance; Underground-miners; Lung-function; Pulmonary-system-disorders; Surveillance
Division of Respiratory Disease Studies, National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention, Morgantown, WV 26505
Journal of Occupational and Environmental Medicine