Emphysema scores predict death from COPD and lung cancer

Abstract

Objective: Our objective was to assess the usefulness of emphysema scores in predicting death from COPD and lung cancer.

Methods: Emphysema was assessed with low-dose CT scans performed on 9,047 men and women for whom age and smoking history were documented. Each scan was scored according to the presence of emphysema as follows: none, mild, moderate, or marked. Follow-up time was calculated from time of CT scan to time of death or December 31, 2007, whichever came first. Cox regression analysis was used to calculate the hazard ratio (HR) of emphysema as a predictor of death.

Results: Median age was 65 years, 4,433 (49%) were men, and 4,133 (46%) were currently smoking or had quit within 5 years. Emphysema was identified in 2,637 (29%) and was a significant predictor of death from COPD (HR, 9.3; 95% CI, 4.3-20.2; P < .0001) and from lung cancer (HR, 1.7; 95% CI, 1.1-2.5; P = .013), even when adjusted for age and smoking history.

Conclusions: Visual assessment of emphysema on CT scan is a significant predictor of death from COPD and lung cancer.

Figure 1.

Kaplan-Meier curves showing an increase in the COPD-specific deaths for participants with emphysema on CT scans. A, Compared with those without emphysema B, As the extent of emphysema increases.

Figure 2.

Kaplan-Meier curves showing an increase in lung cancer-specific mortality for subjects with emphysema on CT scans. A, Compared with those without emphysema. B, As the extent of emphysema increases.