Veterans with Gulf War Illness exhibit distinct respiratory patterns during maximal cardiopulmonary exercise.

INTRODUCTION:The components of minute ventilation, respiratory frequency and tidal volume, appear differentially regulated and thereby afford unique insight into the ventilatory response to exercise. However, respiratory frequency and tidal volume are infrequently reported, and have not previously b...

Full description

Bibliographic Details
Main Authors: Jacob B Lindheimer, Dane B Cook, Jacquelyn C Klein-Adams, Wei Qian, Helene Z Hill, Gudrun Lange, Duncan S Ndirangu, Glenn R Wylie, Michael J Falvo
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2019-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0224833
_version_ 1830358361513656320
author Jacob B Lindheimer
Dane B Cook
Jacquelyn C Klein-Adams
Wei Qian
Helene Z Hill
Gudrun Lange
Duncan S Ndirangu
Glenn R Wylie
Michael J Falvo
author_facet Jacob B Lindheimer
Dane B Cook
Jacquelyn C Klein-Adams
Wei Qian
Helene Z Hill
Gudrun Lange
Duncan S Ndirangu
Glenn R Wylie
Michael J Falvo
author_sort Jacob B Lindheimer
collection DOAJ
description INTRODUCTION:The components of minute ventilation, respiratory frequency and tidal volume, appear differentially regulated and thereby afford unique insight into the ventilatory response to exercise. However, respiratory frequency and tidal volume are infrequently reported, and have not previously been considered among military veterans with Gulf War Illness. Our purpose was to evaluate respiratory frequency and tidal volume in response to a maximal cardiopulmonary exercise test in individuals with and without Gulf War Illness. MATERIALS AND METHODS:20 cases with Gulf War Illness and 14 controls participated in this study and performed maximal cardiopulmonary exercise test on a cycle ergometer. Ventilatory variables (minute ventilation, respiratory frequency and tidal volume) were obtained and normalized to peak exercise capacity. Using mixed-design analysis of variance models, with group and time as factors, we analyzed exercise ventilatory patterns for the entire sample and for 11 subjects from each group matched for race, age, sex, and height. RESULTS:Despite similar minute ventilation (p = 0.57, η2p = 0.01), tidal volume was greater (p = 0.02, η2p = 0.16) and respiratory frequency was lower (p = 0.004, η2p = 0.24) in Veterans with Gulf War Illness than controls. The findings for respiratory frequency remained significant in the matched subgroup (p = 0.004, η2p = 0.35). CONCLUSION:In our sample, veterans with Gulf War Illness adopt a unique exercise ventilatory pattern characterized by reduced respiratory frequency, despite similar ventilation relative to controls. Although the mechanism(s) by which this pattern is achieved remains unresolved, our findings suggest that the components of ventilation should be considered when evaluating clinical conditions with unexplained exertional symptoms.
first_indexed 2024-12-20T02:39:43Z
format Article
id doaj.art-b4a2385e68114ada8fac3976090f9e9f
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-20T02:39:43Z
publishDate 2019-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-b4a2385e68114ada8fac3976090f9e9f2022-12-21T19:56:21ZengPublic Library of Science (PLoS)PLoS ONE1932-62032019-01-011411e022483310.1371/journal.pone.0224833Veterans with Gulf War Illness exhibit distinct respiratory patterns during maximal cardiopulmonary exercise.Jacob B LindheimerDane B CookJacquelyn C Klein-AdamsWei QianHelene Z HillGudrun LangeDuncan S NdiranguGlenn R WylieMichael J FalvoINTRODUCTION:The components of minute ventilation, respiratory frequency and tidal volume, appear differentially regulated and thereby afford unique insight into the ventilatory response to exercise. However, respiratory frequency and tidal volume are infrequently reported, and have not previously been considered among military veterans with Gulf War Illness. Our purpose was to evaluate respiratory frequency and tidal volume in response to a maximal cardiopulmonary exercise test in individuals with and without Gulf War Illness. MATERIALS AND METHODS:20 cases with Gulf War Illness and 14 controls participated in this study and performed maximal cardiopulmonary exercise test on a cycle ergometer. Ventilatory variables (minute ventilation, respiratory frequency and tidal volume) were obtained and normalized to peak exercise capacity. Using mixed-design analysis of variance models, with group and time as factors, we analyzed exercise ventilatory patterns for the entire sample and for 11 subjects from each group matched for race, age, sex, and height. RESULTS:Despite similar minute ventilation (p = 0.57, η2p = 0.01), tidal volume was greater (p = 0.02, η2p = 0.16) and respiratory frequency was lower (p = 0.004, η2p = 0.24) in Veterans with Gulf War Illness than controls. The findings for respiratory frequency remained significant in the matched subgroup (p = 0.004, η2p = 0.35). CONCLUSION:In our sample, veterans with Gulf War Illness adopt a unique exercise ventilatory pattern characterized by reduced respiratory frequency, despite similar ventilation relative to controls. Although the mechanism(s) by which this pattern is achieved remains unresolved, our findings suggest that the components of ventilation should be considered when evaluating clinical conditions with unexplained exertional symptoms.https://doi.org/10.1371/journal.pone.0224833
spellingShingle Jacob B Lindheimer
Dane B Cook
Jacquelyn C Klein-Adams
Wei Qian
Helene Z Hill
Gudrun Lange
Duncan S Ndirangu
Glenn R Wylie
Michael J Falvo
Veterans with Gulf War Illness exhibit distinct respiratory patterns during maximal cardiopulmonary exercise.
PLoS ONE
title Veterans with Gulf War Illness exhibit distinct respiratory patterns during maximal cardiopulmonary exercise.
title_full Veterans with Gulf War Illness exhibit distinct respiratory patterns during maximal cardiopulmonary exercise.
title_fullStr Veterans with Gulf War Illness exhibit distinct respiratory patterns during maximal cardiopulmonary exercise.
title_full_unstemmed Veterans with Gulf War Illness exhibit distinct respiratory patterns during maximal cardiopulmonary exercise.
title_short Veterans with Gulf War Illness exhibit distinct respiratory patterns during maximal cardiopulmonary exercise.
title_sort veterans with gulf war illness exhibit distinct respiratory patterns during maximal cardiopulmonary exercise
url https://doi.org/10.1371/journal.pone.0224833
work_keys_str_mv AT jacobblindheimer veteranswithgulfwarillnessexhibitdistinctrespiratorypatternsduringmaximalcardiopulmonaryexercise
AT danebcook veteranswithgulfwarillnessexhibitdistinctrespiratorypatternsduringmaximalcardiopulmonaryexercise
AT jacquelynckleinadams veteranswithgulfwarillnessexhibitdistinctrespiratorypatternsduringmaximalcardiopulmonaryexercise
AT weiqian veteranswithgulfwarillnessexhibitdistinctrespiratorypatternsduringmaximalcardiopulmonaryexercise
AT helenezhill veteranswithgulfwarillnessexhibitdistinctrespiratorypatternsduringmaximalcardiopulmonaryexercise
AT gudrunlange veteranswithgulfwarillnessexhibitdistinctrespiratorypatternsduringmaximalcardiopulmonaryexercise
AT duncansndirangu veteranswithgulfwarillnessexhibitdistinctrespiratorypatternsduringmaximalcardiopulmonaryexercise
AT glennrwylie veteranswithgulfwarillnessexhibitdistinctrespiratorypatternsduringmaximalcardiopulmonaryexercise
AT michaeljfalvo veteranswithgulfwarillnessexhibitdistinctrespiratorypatternsduringmaximalcardiopulmonaryexercise