Respiratory and immune response to maximal physical exertion following exposure to secondhand smoke in healthy adults

© 2012 The Authors. Published by PLOS. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1371/journal.pone.0031880We assessed the cardiorespiratory and immune response to physical exertion following secondhand smoke (SHS) exposure through a randomized crossover experiment. Data were obtained from 16 (8 women) non-smoking adults during and following a maximal oxygen uptake cycling protocol administered at baseline and at 0-, 1-, and 3- hours following 1-hour of SHS set at bar/restaurant carbon monoxide levels. We found that SHS was associated with a 12% decrease in maximum power output, an 8.2% reduction in maximal oxygen consumption, a 6% increase in perceived exertion, and a 6.7% decrease in time to exhaustion (P<0.05). Moreover, at 0-hours almost all respiratory and immune variables measured were adversely affected (P<0.05). For instance, FEV 1 values at 0-hours dropped by 17.4%, while TNF-α increased by 90.1% (P<0.05). At 3-hours mean values of cotinine, perceived exertion and recovery systolic blood pressure in both sexes, IL4, TNF-α and IFN-γ in men, as well as FEV 1/FVC, percent predicted FEV 1, respiratory rate, and tidal volume in women remained different compared to baseline (P<0.05). It is concluded that a 1-hour of SHS at bar/restaurant levels adversely affects the cardiorespiratory and immune response to maximal physical exertion in healthy nonsmokers for at least three hours following SHS. © 2012 Flouris et al.Published versio

Mean ± SD of cardiorespiratory variables for men and women for the statistically significant post-hoc comparisons.

<p>Note:</p>a<p> = statistically significant (P<0.05) difference from previous measurement.</p>b<p> = statistically significant (P<0.05) difference of <i>T</i>₁ or <i>T</i>₃ from <i>T</i>_B.</p>c<p> = statistically significant (P<0.05) difference between sexes for the same measurement.</p><p>Key: _%Max O₂ uptake: percent predicted maximal oxygen uptake; HR: heart rate; SBP, DBP, and MAP: systolic, diastolic and mean arterial blood pressure, respectively; M: men; W: women.</p

Mean ± SD of cytokine production for men and women for the statistically significant post-hoc comparisons.

<p>Note:</p>a<p> = statistically significant (P<0.05) difference from previous measurement.</p>b<p> = statistically significant (P<0.05) difference of <i>T</i>₁ or <i>T</i>₃ from <i>T</i>_B.</p>c<p> = statistically significant (P<0.05) difference between sexes for the same measurement.</p><p>Key: IL4, 5 and 6: interleukins 4, 5 and 6, respectively; TNF-α: tumor necrosis factor alpha; IFN-γ: interferon gamma; M: men; W: women.</p

Mean ± SD of cotinine and lung function for men and women for the statistically significant post-hoc comparisons.

<p>Note:</p>a<p> = statistically significant (P<0.05) difference from previous measurement.</p>b<p> = statistically significant (P<0.05) difference of <i>T</i>₁ or <i>T</i>₃ from <i>T</i>_B.</p>c<p> = statistically significant (P<0.05) difference between sexes for the same measurement.</p><p>Key: FVC: forced vital capacity; FEV₁: forced expiratory volume in 1 second; _%FEV₁: percent predicted FEV₁; PEF: peak expiratory flow; MEF_75%, MEF_50%, MEF_25%: maximum expiratory flow when 75%, 50% and 25% of FVC remains in the lungs, respectively; MVV: maximum voluntary ventilation; RR: respiratory rate; TV: tidal volume; M: men; W: women.</p

Overview of the experimental protocol.

<p>In the baseline trial (<i>T</i>_B) participants underwent a physical exertion bout that started at 1200 h without any SHS. In the remaining trials, one hour of SHS was administered at either 0800 h (<i>T</i>₃), 1000 h (<i>T</i>₁) or 1100 h (<i>T</i>₀), while the same physical exertion protocol initiated at 1200 h. SHS = secondhand smoke.</p

Correction: Respiratory and Immune Response to Maximal Physical Exertion following Exposure to Secondhand Smoke in Healthy Adults

We assessed the cardiorespiratory and immune response to physical exertion following secondhand smoke (SHS) exposure through a randomized crossover experiment. Data were obtained from 16 (8 women) non-smoking adults during and following a maximal oxygen uptake cycling protocol administered at baseline and at 0-, 1-, and 3- hours following 1-hour of SHS set at bar/restaurant carbon monoxide levels. We found that SHS was associated with a 12% decrease in maximum power output, an 8.2% reduction in maximal oxygen consumption, a 6% increase in perceived exertion, and a 6.7% decrease in time to exhaustion (P<0.05). Moreover, at 0-hours almost all respiratory and immune variables measured were adversely affected (P<0.05). For instance, FEV(1) values at 0-hours dropped by 17.4%, while TNF-α increased by 90.1% (P<0.05). At 3-hours mean values of cotinine, perceived exertion and recovery systolic blood pressure in both sexes, IL4, TNF-α and IFN-γ in men, as well as FEV(1)/FVC, percent predicted FEV(1), respiratory rate, and tidal volume in women remained different compared to baseline (P<0.05). It is concluded that a 1-hour of SHS at bar/restaurant levels adversely affects the cardiorespiratory and immune response to maximal physical exertion in healthy nonsmokers for at least three hours following SHS