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Reduced exercise tolerance and pulmonary capillary recruitment with remote secondhand smoke exposure
Mehrdad Arjomandi1, Thaddeus Haight, Nasrat Sadeghi
1University of California San Francisco Flight Attendants Medical Research Institute Center of Excellence, San Francisco, California, United States of America. mehrdad.arjomandi@ucsf.edu
Plos One
|April 12, 2012
Summary
Never-smoking flight attendants exposed to secondhand smoke (SHS) before flight bans showed exercise limitation due to reduced diffusing capacity (Dco). Years of SHS exposure predicted lower Dco during exercise, indicating impaired pulmonary function.
Area of Science:
- Pulmonary Physiology
- Occupational Health
- Environmental Medicine
Background:
- Flight attendants (FAs) on commercial aircraft before smoking bans experienced significant secondhand smoke (SHS) exposure.
- Previous studies indicated never-smoking pre-ban FAs have reduced resting diffusing capacity (Dco).
Purpose of the Study:
- To investigate if pre-ban FAs exhibit increased Dco and pulmonary blood flow (Qc) during exercise.
- To determine the relationship between resting Dco, exercise capacity, and SHS exposure in this cohort.
Main Methods:
- Symptom-limited, progressively increasing cycle exercise tests were performed by pre-ban FAs.
- Maximum work and oxygen uptake (VO2) were determined, followed by measurements of Dco and Qc at various exercise intensities.
- Participants were grouped based on normal or abnormal resting Dco.
Main Results:
- FAs with abnormal resting Dco achieved lower maximal predicted work and VO2 compared to those with normal resting Dco.
- Reduced Dco increase during exercise and less augmentation of Dco with increasing Qc were observed in FAs with abnormal resting Dco.
- Years of SHS exposure were inversely associated with Dco during exercise in FAs with ≥10 years of pre-ban experience.
Conclusions:
- Never-smoking pre-ban FAs with SHS exposure demonstrated exercise limitation linked to resting Dco.
- Lower resting Dco was associated with reduced pulmonary capillary recruitment during exercise.
- Aircraft cabin SHS exposure appears to be a predictor of diminished Dco during physical exertion.
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