Predictors of mortality in patients with emphysema and severe airflow obstruction.
OBJECTIVE
Limited data exist describing risk factors for mortality in patients having predominantly emphysema.


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).


CONCLUSIONS
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.
Division of Pulmonary and Critical Care Medicine, University of Michigan Health System, Ann Arbor, MI 48109-0360, and Section of Thoracic Surgery, Beth Israel Deaconess Medical Center, Boston, MA, USA. fmartine@umich.edu
Fernando J
FJ
Martinez
Gregory
G
Foster
Jeffrey L
JL
Curtis
Gerard
G
Criner
Gail
G
Weinmann
Alfred
A
Fishman
Malcolm M
MM
DeCamp
Joshua
J
Benditt
Frank
F
Sciurba
Barry
B
Make
Zab
Z
Mohsenifar
Philip
P
Diaz
Eric
E
Hoffman
Robert
R
Wise
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D015331:Cohort Studies; D004417:Dyspnea / Q000503:physiopathology; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D005544:Forecasting; D006801:Humans; D008297:Male; D008875:Middle Aged; D010102:Oxygen Inhalation Therapy; D029424:Pulmonary Disease, Chronic Obstructive / Q000401:mortality* / Q000503:physiopathology; D011656:Pulmonary Emphysema / Q000401:mortality* / Q000503:physiopathology; D011788:Quality of Life; D012115:Residual Volume / Q000502:physiology; D012307:Risk Factors; D012907:Smoking / Q000503:physiopathology; D014109:Total Lung Capacity / Q000502:physiology; D014692:Ventilation-Perfusion Ratio / Q000502:physiology