Predictors of mortality in patients with emphysema and severe airflow obstruction

Am J Respir Crit Care Med. 2006 Jun 15;173(12):1326-34. doi: 10.1164/rccm.200510-1677OC. Epub 2006 Mar 16.

Abstract

Purpose: Limited data exist describing risk factors for mortality in patients having predominantly emphysema.

Subjects and methods: A total of 609 patients with severe emphysema (ages 40-83 yr; 64.2% male) randomized to the medical therapy arm of the National Emphysema Treatment Trial formed the study group. Cox proportional hazards regression analysis was used to investigate risk factors for all-cause mortality. Risk factors examined included demographics, body mass index, physiologic data, quality of life, dyspnea, oxygen utilization, hemoglobin, smoking history, quantitative emphysema markers on computed tomography, and a modification of a recently described multifunctional index (modified BODE).

Results: Overall, high mortality was seen in this cohort (12.7 deaths per 100 person-years; 292 total deaths). In multivariate analyses, increasing age (p=0.001), oxygen utilization (p=0.04), lower total lung capacity % predicted (p=0.05), higher residual volume % predicted (p=0.04), lower maximal cardiopulmonary exercise testing workload (p=0.002), greater proportion of emphysema in the lower lung zone versus the upper lung zone (p=0.005), and lower upper-to-lower-lung perfusion ratio (p=0.007), and modified BODE (p=0.02) were predictive of mortality. FEV1 was a significant predictor of mortality in univariate analysis (p=0.005), but not in multivariate analysis (p=0.21).

Conclusion: Although patients with advanced emphysema experience significant mortality, subgroups based on age, oxygen utilization, physiologic measures, exercise capacity, and emphysema distribution identify those at increased risk of death.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Body Mass Index
  • Cohort Studies
  • Dyspnea / physiopathology
  • Exercise Tolerance / physiology
  • Female
  • Forced Expiratory Volume / physiology
  • Forecasting
  • Humans
  • Male
  • Middle Aged
  • Oxygen Inhalation Therapy
  • Pulmonary Disease, Chronic Obstructive / mortality*
  • Pulmonary Disease, Chronic Obstructive / physiopathology
  • Pulmonary Emphysema / mortality*
  • Pulmonary Emphysema / physiopathology
  • Quality of Life
  • Residual Volume / physiology
  • Risk Factors
  • Smoking / physiopathology
  • Total Lung Capacity / physiology
  • Ventilation-Perfusion Ratio / physiology