Lusk CM, et al. - Researchers analyzed a sample of former and current smokers to characterize the spectrum of chronic obstructive pulmonary disease (COPD)-related phenotypes and to evaluate the difference between the sub-groups in terms of sociodemographic characteristics, COPD-related co-morbidities, and subsequent risk of lung cancer. They defined distinct COPD-related sub-groups based on hierarchical clustering using white (N=659) and African American (N=520) male and female participants without lung cancer (controls) in the INHALE study who completed a chest CT scan, interview and spirometry test. Seven variables used to define clusters were pack years, quit years, FEV1/FVC, % predicted FEV1 and from quantitative CT imaging, % emphysema, % air trapping and mean lung density ratio. They noted an increased risk of lung cancer in association with increasingly detrimental lung function clusters (when ordered from most detrimental to least detrimental). Smokers display considerable variations in measures of lung function that are not fully explained by smoking intensity. A spectrum of lung disease obtained on combining clinical (spirometry) and radiologic (quantitative CT) measures of COPD may predict lung cancer risk differentially among patient clusters.