| Title |
The inspiratory capacity/total lung capacity ratio as a predictor of survival in an emphysematous phenotype of chronic obstructive pulmonary disease
|
|---|---|
| Published in |
International Journal of Chronic Obstructive Pulmonary Disease, July 2015
|
| DOI | 10.2147/copd.s76739 |
| Pubmed ID | |
| Authors |
Aimee French, David Balfe, James M Mirocha, Jeremy A Falk, Zab Mosenifar |
| Abstract |
Forced expiratory volume in 1 second (FEV1) grades severity of COPD and predicts survival. We hypothesize that the inspiratory capacity/total lung capacity (IC/TLC) ratio, a sensitive measure of static lung hyperinflation, may have a significant association with survival in an emphysematous phenotype of COPD. To access the association between IC/TLC and survival in an emphysematous phenotype of COPD. We performed a retrospective analysis of a large pulmonary function (PF) database with 39,050 entries, from April 1978 to October 2009. Emphysematous COPD was defined as reduced FEV1/forced vital capacity (FVC), increased TLC, and reduced diffusing capacity of the lungs for carbon monoxide (DLCO; beyond 95% confidence intervals [CIs]). We evaluated the association between survival in emphysematous COPD patients and the IC/TLC ratio evaluated both as dichotomous (≤25% vs >25%) and continuous predictors. Five hundred and ninety-six patients had reported death dates. Univariate analysis revealed that IC/TLC ≤25% was a significant predictor of death (hazard ratio [HR]: 2.39, P<0.0001). Median survivals were respectively 4.3 (95% CI: 3.8-4.9) and 11.9 years (95% CI: 10.3-13.2). Multivariable analysis revealed age (HR: 1.19, 95% CI: 1.14-1.24), female sex (HR: 0.69, 95% CI: 0.60-0.83), and IC/TLC ≤25% (HR: 1.69, 95% CI: 1.34-2.13) were related to the risk of death. Univariate analysis showed that continuous IC/TLC was associated with death, with an HR of 1.66 (95% CI: 1.52-1.81) for a 10% decrease in IC/TLC. Adjusting for age and sex, IC/TLC ≤25% is related to increased risk of death, and IC/TLC as a continuum, is a significant predictor of mortality in emphysematous COPD patients. |
X Demographics
The data shown below were collected from the profile of 1 X user who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 1 | 100% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Practitioners (doctors, other healthcare professionals) | 1 | 100% |
Mendeley readers
The data shown below were compiled from readership statistics for 49 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Brazil | 1 | 2% |
| Unknown | 48 | 98% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Master | 11 | 22% |
| Researcher | 7 | 14% |
| Student > Doctoral Student | 6 | 12% |
| Student > Ph. D. Student | 6 | 12% |
| Student > Bachelor | 4 | 8% |
| Other | 12 | 24% |
| Unknown | 3 | 6% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 25 | 51% |
| Nursing and Health Professions | 7 | 14% |
| Agricultural and Biological Sciences | 3 | 6% |
| Biochemistry, Genetics and Molecular Biology | 2 | 4% |
| Mathematics | 1 | 2% |
| Other | 4 | 8% |
| Unknown | 7 | 14% |
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 14 July 2015.
All research outputs
#20,656,161
of 25,374,647 outputs
Outputs from International Journal of Chronic Obstructive Pulmonary Disease
#2,078
of 2,577 outputs
Outputs of similar age
#202,783
of 277,610 outputs
Outputs of similar age from International Journal of Chronic Obstructive Pulmonary Disease
#62
of 79 outputs
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