Longitudinal limits of normal decline in lung function in an individual

J Occup Environ Med. 2006 Jun;48(6):625-34. doi: 10.1097/01.jom.0000214351.18905.48.


Objectives: The objectives of this study were to propose a method of calculating longitudinal limits of normal decline (LND) in forced expiratory volume in 1 second to identify individuals with an excessive decline in lung function and to compare the method with other published LND methods.

Methods: We used longitudinal data from 11 workplace-based spirometric monitoring programs conducted from 1987 to 2001 on 12,729 workers to evaluate effectiveness of each LND method in identifying a "true" excessive decline in forced expiratory volume in 1 second defined using two criteria: slope >60 mL/year or >90 mL/year estimated over 5 or more years of follow up.

Results: In comparison to the LND proposed by the American College of Occupational and Environmental Medicine, the proposed method had 5.0 to 2.7 times higher sensitivity over years 1 through 5 for the >60-mL/yr criterion.

Conclusions: The proposed LND method was more effective than the other methods for identifying excessive declines.

MeSH terms

  • Adult
  • Female
  • Forced Expiratory Volume
  • Humans
  • Lung / physiology*
  • Male
  • Predictive Value of Tests
  • Reference Values
  • Respiratory Function Tests*
  • Sensitivity and Specificity
  • Spirometry