Duo of chest CT studies provide new clues for improved management of COPD, other lung diseases

Doctor at appointment examines CT scan of chest and abdominal cavity.

Chest CT (computerized tomography) scans have long been used to evaluate the health of the lungs and other organs. Now, a duo of chest CT studies provide new clues for the improved management of COPD and other lung diseases, with a focus on fatty tissue. 

In one study, researchers are reporting that soft-tissue biomarkers provided from routine chest CT scans can provide important information about the overall health of people with chronic obstructive pulmonary disease (COPD), including their risk of death.  The study could lead to earlier intervention and reduced risk, they say. It was funded in part by the NHLBI and appeared in the journal Radiology.

In the study, researchers used chest CT exams to examine the associations between soft tissue quality, bone density, or degeneration of the spine as an index of overall health, biomarkers that are markers, including fat and muscle, and all-cause mortality in people with COPD. The researchers used data from almost 3,000 participants in the NHLBI-funded Multi-Ethnic Study of Atherosclerosis (MESA) study, which is investigating the roles of imaging-derived soft-tissue and bone markers for predicting outcomes of cardiovascular disease.  Of the 265 patients in the study with COPD, 49 (18%) died over the follow-up period.

The new study found that intermuscular fat, which is linked to diabetes and insulin resistance, was associated with higher death rates in these patients. By contrast, higher levels of subcutaneous fat were associated with lower risks of death. A better understanding of body composition assessments from chest CT could lead to earlier health interventions in COPD patients who are at higher risk for adverse health events, the researchers suggest.

In a similar study, another group of researchers found that higher levels fatty tissue surrounding the heart and abdominal organs (liver, intestines, kidneys) was associated with lung abnormalities among the MESA participants. That study also suggests that fat tissue may actually cause lung injury that is detectable on CT scan, the researchers said. A better understanding of how fat affects the lungs could lead to better management of lung disease, they noted. The study was funded in part by the NHLBI and appeared in the journal Chest.