| Title |
The association of tidal EFL with exercise performance, exacerbations, and death in COPD
|
|---|---|
| Published in |
International Journal of Chronic Obstructive Pulmonary Disease, July 2017
|
| DOI | 10.2147/copd.s138720 |
| Pubmed ID | |
| Authors |
Bernt Boegvald Aarli, Peter MA Calverley, Robert L Jensen, Raffaele Dellacà, Tomas ML Eagan, Per S Bakke, Jon A Hardie |
| Abstract |
Tidal expiratory flow limitation (EFLT) is frequently found in patients with COPD and can be detected by forced oscillations when within-breath reactance of a single-breath is ≥0.28 kPa·s·L(-1). The present study explored the association of within-breath reactance measured over multiple breaths and EFLT with 6-minute walk distance (6MWD), exacerbations, and mortality. In 425 patients, spirometry and forced oscillation technique measurements were obtained on eight occasions over 3 years. 6MWD was assessed at baseline and at the 3-year visit. Respiratory symptoms, exacerbations, and hospitalizations were recorded. A total of 5-year mortality statistics were retrieved retrospectively. We grouped patients according to the mean within-breath reactance [Formula: see text], measured over several breaths at baseline, calculated as mean inspiratory-mean expiratory reactance over the sampling period. In addition to the established threshold of EFLT, an upper limit of normal (ULN) was defined using the 97.5th percentile of [Formula: see text], of the healthy controls in the study; 6MWDs were compared according to [Formula: see text], as normal, ≥ ULN < EFLT, or ≥ EFLT. Annual exacerbation rates were analyzed using a negative binomial model in the three groups, supplemented by time to first exacerbation analysis, and dichotomizing patients at the ULN. In patients with COPD and baseline [Formula: see text] below the ULN (0.09 kPa·s·L(-1)), 6MWD was stable. 6MWD declined significantly in patients with [Formula: see text]. Worse lung function and more exacerbations were found in patients with COPD with [Formula: see text], and patients with [Formula: see text] had shorter time to first exacerbation and hospitalization. A significantly higher mortality was found in patients with [Formula: see text] and FEV1 >50%. Patients with baseline [Formula: see text] had a deterioration in exercise performance, more exacerbations, and greater hospitalizations, and, among those with moderate airway obstruction, a higher mortality. [Formula: see text] is a novel independent marker of outcome in COPD. |
X Demographics
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Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 1 | 100% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 1 | 100% |
Mendeley readers
The data shown below were compiled from readership statistics for 44 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 44 | 100% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Master | 9 | 20% |
| Researcher | 7 | 16% |
| Student > Bachelor | 2 | 5% |
| Professor > Associate Professor | 2 | 5% |
| Student > Ph. D. Student | 2 | 5% |
| Other | 5 | 11% |
| Unknown | 17 | 39% |
| Readers by discipline | Count | As % |
|---|---|---|
| Nursing and Health Professions | 11 | 25% |
| Medicine and Dentistry | 8 | 18% |
| Engineering | 4 | 9% |
| Psychology | 1 | 2% |
| Agricultural and Biological Sciences | 1 | 2% |
| Other | 0 | 0% |
| Unknown | 19 | 43% |
Attention Score in Context
This research output has an Altmetric Attention Score of 1. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 09 May 2018.
All research outputs
#20,660,571
of 25,382,440 outputs
Outputs from International Journal of Chronic Obstructive Pulmonary Disease
#2,079
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Outputs of similar age
#252,263
of 326,871 outputs
Outputs of similar age from International Journal of Chronic Obstructive Pulmonary Disease
#70
of 82 outputs
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