Interstitial Features at Chest CT Enhance the Deleterious Effects of Emphysema in the COPDGene Cohort

Abstract

Purpose To determine if interstitial features at chest CT enhance the effect of emphysema on clinical disease severity in smokers without clinical pulmonary fibrosis. Materials and Methods In this retrospective cohort study, an objective CT analysis tool was used to measure interstitial features (reticular changes, honeycombing, centrilobular nodules, linear scar, nodular changes, subpleural lines, and ground-glass opacities) and emphysema in 8266 participants in a study of chronic obstructive pulmonary disease (COPD) called COPDGene (recruited between October 2006 and January 2011). Additive differences in patients with emphysema with interstitial features and in those without interstitial features were analyzed by using t tests, multivariable linear regression, and Kaplan-Meier analysis. Multivariable linear and Cox regression were used to determine if interstitial features modified the effect of continuously measured emphysema on clinical measures of disease severity and mortality. Results Compared with individuals with emphysema alone, those with emphysema and interstitial features had a higher percentage predicted forced expiratory volume in 1 second (absolute difference, 6.4%; P < .001), a lower percentage predicted diffusing capacity of lung for carbon monoxide (Dlco) (absolute difference, 7.4%; P = .034), a 0.019 higher right ventricular–to–left ventricular (RVLV) volume ratio (P = .029), a 43.2-m shorter 6-minute walk distance (6MWD) (P < .001), a 5.9-point higher St George’s Respiratory Questionnaire (SGRQ) score (P < .001), and 82% higher mortality (P < .001). In addition, interstitial features modified the effect of emphysema on percentage predicted Dlco, RVLV volume ratio, 6WMD, SGRQ score, and mortality (P for interaction < .05 for all). Conclusion In smokers, the combined presence of interstitial features and emphysema was associated with worse clinical disease severity and higher mortality than was emphysema alone. In addition, interstitial features enhanced the deleterious effects of emphysema on clinical disease severity and mortality.

Imaging Advances in Chronic Obstructive Pulmonary Disease. Insights from the Genetic Epidemiology of Chronic Obstructive Pulmonary Disease (COPDGene) Study

“…Objective approaches have been developed to identify ILAs and may identify clinically and genetically relevant abnormalities even in cases where ILA is not subjectively visible (62,64,65).…”

Interstitial Lung Abnormality: Recognition and Perspectives

“…ILA progression was associated with a more rapid decrease in pulmonary function and an increased risk of death (hazard ratio: 3.9; 95% confidence interval: 1.3, 10.9; P = .01) (11). techniques, such as hyperpolarized xenon 129 spectroscopy, and machine learning may assist with evaluation and follow-up of ILA (19)(20)(21)(22)(23)(24). It is time for radiologists to stop attributing ILA to a benign age-related finding, as these changes have been clearly shown to be associated with increased mortality, increased risk of ARDS, and a decrease in pulmonary function over time.…”

Distinguishing Smoking-Related Lung Disease Phenotypes Via Imaging and Molecular Features

“…The DECAMP study is supported by funds from the Department of Defense (W81XWH-11-2-0161), emphysema-like tissue with the use of a local histogram-based technique, (2) the measurement of pectoralis muscle area (expressed in square centimeters) that is performed on a single axial image above the level of the aortic arch, and (3) airway wall thickness as defined by the mean thickness of 6 segmental airways from each subject. [20][21][22][23][24][25][26][27][28][29] Further details and supplemental analyses with an expanded list of quantitative measures are available in the Online Supplement.…”