Chest
Volume 137, Issue 5, May 2010, Pages 1116-1121
Journal home page for Chest

ORIGINAL RESEARCH
COPD
Dynamic Hyperinflation During Daily Activities: Does COPD Global Initiative for Chronic Obstructive Lung Disease Stage Matter?

https://doi.org/10.1378/chest.09-1847Get rights and content

Background

One of the contributors to exercise limitation in COPD is dynamic hyperinflation. Although dynamic hyperinflation appears to occur during several exercise protocols in COPD and seems to increase with increasing disease severity, it is unknown whether dynamic hyperinflation occurs at different severity stages according to the Global initiative for chronic Obstructive Lung Disease (GOLD) in daily life. The present study, therefore, aimed to compare dynamic hyperinflation between COPD GOLD stages II-IV during daily activities.

Methods

Thirty-two clinically stable patients with COPD GOLD II (n = 10), III (n = 12), and IV (n = 10) participated in this study. Respiratory physiology during a daily activity was measured at patients' homes with Oxycon Mobile. Inspiratory capacity maneuvers were performed at rest, at 2-min intervals during the activity, and at the end of the activity. Change in inspiratory capacity is commonly used to reflect change in end-expiratory lung volume (ΔEELV) and, therefore, dynamic hyperinflation. The combination of static and dynamic hyperinflation was reflected by inspiratory reserve volume (IRV) during the activity.

Results

Overall, increase in EELV occurred in GOLD II-IV without significant difference between the groups. There was a tendency for a smaller ΔEELV in GOLD IV. ΔEELV was inversely related to static hyperinflation. IRV during the daily activity was related to the level of airflow obstruction.

Conclusions

Dynamic hyperinflation occurs independent of GOLD stage during real-life daily activities. The combination of static and dynamic hyperinflation, however, increases with increasing airflow obstruction.

Section snippets

Subjects

Thirty-two clinically stable patients with COPD, GOLD stage II (n = 10), III (n = 12), and IV (n = 10), participated in this study. Patients were recruited from our outpatient clinic. Exclusion criteria were long-term oxygen therapy, respiratory insufficiency, asthma, exercise-limiting comorbidity, or an exacerbation within 4 weeks before the study. The study was conducted according to the Declaration of Helsinki and was approved by the medical ethical committee of our hospital. Written

Subjects

Age, gender, and BMI were comparable across the GOLD groups (Table 1). Smoking history was similar between the groups (II, 38 ± 9; III, 34 ± 5; IV, 32 ± 5 pack-years). All but three patients used long-acting bronchodilation. GOLD IV subjects showed significantly lower ICrest and ICrest/TLC ratios than GOLD II and III subjects (Table 1), reflecting more static hyperinflation. According to the MMRC and CCQ scores, patients with more severe disease were more disabled.

ADLs

Activities varied from vacuum

Discussion

We showed in this study for the first time that DH occurred independent of disease severity according to GOLD during real-life ADLs. There was a tendency for less DH in the most severe COPD group. The amount of DH was at least partially determined by the level of static hyperinflation as reflected by ICrest or ICrest/TLC.

With increasing GOLD stage, scores of disability increased, which was reflected by the choice of less heavy tasks (tendency to lower V.o2), shorter ADL time, and more

Acknowledgments

Author contributions: Dr Hannink: contributed to designing the study, performing all measurements and data analyses, writing the manuscript, and reading and approving the final manuscript.

Dr van Helvoort: contributed to providing guidance for the development of the study design and interpretation of the results, providing comments on the manuscript, and reading and approving the final manuscript.

Dr Dekhuijzen: contributed to providing guidance for the development of the study design, providing

References (0)

Cited by (0)

Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (www.chestpubs.org/site/misc/reprints.xhtml).

View full text