Dataset Information

Chemosensitivity, Cardiovascular Risk, and the Ventilatory Response to Exercise in COPD.

ABSTRACT:

Unlabelled

COPD is associated with elevated cardiovascular risk and a potentiated ventilatory response to exercise. Enhanced carotid chemoreceptor (CC) activity/sensitivity is present in other clinical conditions, has been shown to contribute to sympathetic vasoconstrictor outflow, and is predictive of mortality. CC activity/sensitivity, and the resulting functional significance, has not been well examined in COPD. We hypothesized that CC activity/sensitivity would be elevated in COPD, and related to increased pulse wave velocity (a marker of CV risk) and the ventilatory response to exercise.

Methods

30 COPD patients and 10 healthy age-matched controls were examined. Participants performed baseline cardiopulmonary exercise and pulmonary function testing. CC activity was later evaluated by the drop in ventilation with breathing 100% O2, and CC sensitivity was then assessed by the ventilatory response to hypoxia (?VE/?SpO2). Peripheral arterial stiffness was subsequently evaluated by measurement of pulse wave velocity (PWV) using applanation tonometry while the subjects were breathing room air, and then following chemoreceptor inhibition by breathing 100% O2 for 2 minutes.

Results

CC activity, CC sensitivity, PWV and the ventilatory response to exercise were all increased in COPD relative to controls. CC sensitivity was related to PWV; however, neither CC activity nor CC sensitivity was related to the ventilatory response to exercise in COPD. CC inhibition by breathing 100% O2 normalized PWV in COPD, while no effect was observed in controls.

Conclusion

CC activity and sensitivity are elevated in COPD, and appear related to cardiovascular risk; however, CC activity/sensitivity does not contribute to the potentiated ventilatory response to exercise.

SUBMITTER: Stickland MK

PROVIDER: S-EPMC4927073 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Chemosensitivity, Cardiovascular Risk, and the Ventilatory Response to Exercise in COPD.

Stickland Michael K MK Fuhr Desi P DP Edgell Heather H Byers Brad W BW Bhutani Mohit M Wong Eric Y L EY Steinback Craig D CD

PloS one 20160629 6

<h4>Unlabelled</h4>COPD is associated with elevated cardiovascular risk and a potentiated ventilatory response to exercise. Enhanced carotid chemoreceptor (CC) activity/sensitivity is present in other clinical conditions, has been shown to contribute to sympathetic vasoconstrictor outflow, and is predictive of mortality. CC activity/sensitivity, and the resulting functional significance, has not been well examined in COPD. We hypothesized that CC activity/sensitivity would be elevated in COPD, a ...[more]

PMID: 27355356

Similar Datasets

Project description:Alterations in respiratory mechanics predispose healthy obese individuals to low lung volume breathing, which places them at risk of developing expiratory flow limitation (EFL). The high ventilatory demand in endurance-trained obese adults further increases their risk of developing EFL and increases their work of breathing. The objective of this study was to investigate the prevalence and magnitude of EFL in fit obese (FO) adults via measurements of breathing mechanics and ventilatory dynamics during exercise.Ten (seven women and three men) FO (mean ± SD, 38 ± 5 years, 38% ± 5% body fat) and 10 (seven women and three men) control obese (CO) (38 ± 5 years, 39% ± 5% body fat) subjects underwent hydrostatic weighing, pulmonary function testing, cycle exercise testing, and the determination of the oxygen cost of breathing during eucapnic voluntary hyperpnea.There were no differences in functional residual capacity (43% ± 6% vs 40% ± 9% total lung capacity [TLC]), residual volume (21% ± 4% vs 21% ± 4% TLC), or FVC (111% ± 13% vs 104% ± 15% predicted) between FO and CO subjects, respectively. FO subjects had higher FEV1 (111% ± 13% vs 99% ± 11% predicted), TLC (106% ± 14% vs 94% ± 7% predicted), peak expiratory flow (123% ± 14% vs 106% ± 13% predicted), and maximal voluntary ventilation (128% ± 15% vs 106% ± 13% predicted) than did CO subjects. Peak oxygen uptake (129% ± 16% vs 86% ± 15% predicted), minute ventilation (128 ± 35 L/min vs 92 ± 25 L/min), and work rate (229 ± 54 W vs 166 ± 55 W) were higher in FO subjects. Mean inspiratory (4.65 ± 1.09 L/s vs 3.06 ± 1.21 L/s) and expiratory (4.15 ± 0.95 L/s vs 2.98 ± 0.76 L/s) flows were greater in FO subjects, which yielded a greater breathing frequency (51 ± 8 breaths/min vs 41 ± 10 breaths/min) at peak exercise in FO subjects. Mechanical ventilatory constraints in FO subjects were similar to those in CO subjects despite the greater ventilatory demand in FO subjects.FO individuals achieve high ventilations by increasing breathing frequency, matching the elevated metabolic demand associated with high fitness. They do this without developing meaningful ventilatory constraints. Therefore, endurance-trained obese individuals with higher lung function are not limited by breathing mechanics during peak exercise, which may allow healthy obese adults to participate in vigorous exercise training.

Project description:BackgroundSarcopenia is a well-established risk factor for atherosclerotic cardiovascular disease (ASCVD), but its relationship with chronic obstructive pulmonary disease (COPD) has not been fully determined. This study is aimed to investigate the association between sarcopenia and risk for ASCVD in patients with COPD, independent of central obesity and fat mass.MethodsData regarding 704 men with COPD (mean age: 63.4 years) were extracted from the 2008 to 2011 Korean National Health and Nutrition Examination Surveys. Sarcopenia index and fat mass were assessed using dual-energy X-ray absorptiometry. Sarcopenia was defined according to the presence of sarcopenia index values < 1 standard deviation from the cutoff (0.774) among the study participants. ASCVD risk was evaluated using American College of Cardiology/American Heart Association guidelines. High probability of ASCVD was defined as ASCVD risk > 20%.ResultsThe quartile-stratified sarcopenia index was negatively associated with ASCVD risk (P < 0.001). ASCVD risk and prevalence of high ASCVD risk were significantly greater in sarcopenic participants than in non-sarcopenic participants, regardless of central obesity and fat mass (all P < 0.001). Multivariate regression analyses demonstrated an independent association between sarcopenia and ASCVD risk (estimated ± standard error = 3.63 ± 0.77%, P < 0.001) and high ASCVD risk (odds ratio [OR] = 2.32, 95% confidence interval [CI] 1.05-5.15, P = 0.039). Furthermore, sarcopenia was an independent factor for high ASCVD risk in participants with moderate to very severe airflow limitation (OR = 2.97, 95% CI 1.06-8.36, P < 0.001).ConclusionsSarcopenia was significantly associated with an increased risk for ASCVD in men with COPD, independent of central obesity and fat mass. High ASCVD risk was significantly associated with sarcopenia, particularly in participants with moderate to very severe airflow limitation.

Dataset Information

Chemosensitivity, Cardiovascular Risk, and the Ventilatory Response to Exercise in COPD.

Unlabelled

Methods

Results

Conclusion

Publications

Chemosensitivity, Cardiovascular Risk, and the Ventilatory Response to Exercise in COPD.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets