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

Autoři: Jacob B. Lindheimer aff001;  Dane B. Cook aff002;  Jacquelyn C. Klein-Adams aff001;  Wei Qian aff001;  Helene Z. Hill aff004;  Gudrun Lange aff005;  Duncan S. Ndirangu aff001;  Glenn R. Wylie aff001;  Michael J. Falvo aff001
Působiště autorů: War Related Illness and Injury Study Center, Department of Veterans Affairs New Jersey Health Care System, East Orange, New Jersey, United States of America aff001;  William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States of America aff002;  Department of Kinesiology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America aff003;  New Jersey Medical School, Rutgers Biomedical and Health Sciences, Newark, New Jersey, United States of America aff004;  Department of Neurology, Mount Sinai Beth Israel, New York, New York, Unites States of America aff005;  Kessler Foundation, West Orange, New Jersey, United States of America aff006
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0224833



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.


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).


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.

Klíčová slova:

Breathing – Exercise – Pain sensation – Spirometry – Sports and exercise medicine – Tidal volume – Veterans – Gulf War syndrome


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