Lower limit of normal based spirometric abnormalities associated with radiographic abnormality in an elderly cohort at low risk for exposure

Abstract

Background: Although the relation between radiographic abnormalities and spirometric impairment in people with asbestosis has been studied extensively, the extent of spirometric impairment associated with milder radiographic abnormalities is not established.

Objective: To test associations between mild radiographic abnormalities and Lower Limit of Normal (LLN)-based spirometry interpretation.

Methods: Spirometry and CXRs were collected for 1,026 at low risk of exposure to pneumoconiotic agents participants in a medical screening program.

Results: Individuals with each type of isolated or combined International Labour Organization (ILO) abnormalities had up to over sixfold statistically significant increase in odds of LLN-based restrictive pattern physiology (OR = 1.96, 95%CI 1.03–3.73 for parenchymal to OR = 6.09, 95%CI 1.94–19.10 for parenchymal and pleural) compared to those with normal films.

Conclusions: The findings from this study confirm the association of mild profusion abnormalities with clinically relevant, LLN-based lung function abnormalities.

Keywords:

• Pneumoconiosis
• ILO
• Spirometry
• Spirometric abnormalities
• Lower limit of normal

Acknowledgments

This study would not have been possible without the participation of former workers from both DoE sites under study. We remain thankful to those workers as well as DoE staff, Mary Fields, Greg Lewis, Isaf Al-Nabulsi, Moriah Ferullo, Regina Cano, Libby White, and Dr. Patricia Worthington for their support toward the program. We would like to thank the University of Iowa team; Nicholas Hoeger, Christina Nichols, Jill Welch, Rick Paulos, and Dr Valentina Clottey for their ongoing contributions to the screening program.