Table 1.

Tools Other Than Pulmonary Function Tests to Detect Impaired Respiratory Health

Tool	Associations
Molecular biomarkers
CRP, fibrinogen	Reduced FVC, reduced FEV1; future emphysema
ICAM-1	Reduced FVC, reduced FEV1; future emphysema, high-attenuation areas, ILA, IPF, ILD-specific death
MMP-7	Reduced FVC, exertional dyspnea, ILA, all-cause mortality
Assessment of symptoms
Cough or phlegm	Decline in FVC, decline in FEV1; future obstructive physiology, future emphysema
Respiratory illnesses	Decline in FVC, decline in FEV1; future obstructive physiology, future emphysema
Shortness of breath	Future restrictive physiology, increased all-cause mortality
COPD Assessment Test score > 10 in smokers without COPD	Reduced FVC, reduced FEV1, respiratory exacerbations requiring use of antibiotics or corticosteroids
CT imaging
Low-attenuation areas	Increased all-cause mortality in a general population without COPD
High-attenuation areas	Lower FVC; future ILA, ILD-specific hospitalizations, ILD-specific mortality, all-cause mortality
ILA	Reduced lung capacity, reduced exercise capacity, reduced gas exchange, all-cause mortality

CRP = C-reactive protein; ICAM = intercellular adhesion molecule; ILA = interstitial lung abnormalities; ILD = interstitial lung disease; IPF = idiopathic pulmonary fibrosis; MMP = matrix metalloproteinase.