- 作者：Alastair J. Moore ; Rosa Suades Soler ; Edward J. Cetti ; S. Am ; a Sathyapala ; Nicholas S. Hopkinson ; Michael Roughton ; John Moxham ; Michael I. Polkey
- 关键词：COPD ; Respiratory muscle strength ; Hyperinflation
- 刊名：Respiratory Medicine
- 出版年：2010
- 出版时间：September 2010
- 年：2010
- 卷：104
- 期：9
- 页码：1319-1325
- 全文大小：360 K
Summary
BackgroundHyperinflation is a recognized adverse prognostic factor in COPD. As the sniff inspiratory nasal pressure (SnIP) principally reflects the severity of hyperinflation in COPD, we hypothesized that it might also be a predictor of mortality. We therefore compared the SnIP to the inspiratory capacity-to-total lung capacity (IC/TLC) ratio as predictors of mortality in advanced COPD.Methods
A retrospective mortality analysis of 110 patients with COPD (mean FEV1 1.01 litres, 37 % predicted; 66 % male) was performed. All patients had SnIP and lung volume measurements performed. The power of each test to predict mortality was determined, and predicted survival curves were created for both the SnIP and IC/TLC ratio.
Results
37 patients (34 % ) died during the study period (29 male, 8 female). Mortality rates were analysed with a Chi2 test; there was a significant trend towards male death (mortality rate male vs. female; 39.7 % vs. 21.6 % respectively; χ2 p = 0.058, Chi 3.6). ROC curves demonstrated that both SnIP and IC/TLC ratio are predictors of mortality, but analysis by Cox proportional hazards suggested the SnIP has a stronger predictive power (SnIP vs. IC/TLC ratio; p = 0.017 vs 0.525; HR 0.97 vs 0.99 respectively), and analysis of the area under ROC curves (AUC) suggest that SnIP is a better discriminator than IC/TLC ratio (AUC SnIP vs IC/TLC; 0.679 vs 0.618).
Conclusions
The SnIP conveys at least as much predictive power for mortality in COPD as hyperinflation determined by IC/TLC ratio. This test is cheaper, quicker and easier than measuring lung volumes by plethysmography.