CT-derived body composition assessment may signal mortality risk in COPD

Body composition information derived from routine chest CT may provide insights on the overall health and risk for mortality among patients with COPD, researchers reported in Radiology.

“Chest CT examinations are routinely performed in patients with COPD and the availability of these examinations may allow assessment of the distribution of adipose depots and sarcopenia for predicting risks of mortality,” Farhad Pishgar, MD, MPH, postdoctoral research fellow in the Russell H. Morgan department of radiology and radiological science at Johns Hopkins University School of Medicine, and colleagues wrote.

The researchers conducted a secondary analysis of 2,994 participants (mean age, 69 years) from the Multi-Ethnic Study of Atherosclerosis (MESA) with available chest CT scans from 2010 to 2012. Researchers analyzed CT scans to determine subcutaneous adipose tissue, intermuscular adipose tissue and pectoralis muscle areas and spirometry evaluations to establish COPD diagnosis. The researchers’ aim was to evaluate associations between soft-tissue markers from chest CT and mortality in those with COPD.

Overall, 265 participants had COPD (mean age, 72 years; 162 men) and 18% of these participants died during follow-up.

The markers had moderate to excellent intrareader and interreader reliabilities (intraclass correlation coefficient, 0.88-0.99), the researchers reported.

Among all participants, the subcutaneous adipose tissue (0.8; 95% CI, 0.78-0.81) and intermuscular adipose tissue (0.37; 95% CI, 0.34-0.41) indexes correlated with fat mass index (P < .001 for both). Among participants with COPD, those with a higher subcutaneous adipose tissue index had lower risk for mortality (HR = 0.2; 95% CI, 0.1-0.4; P < .001), whereas those with a higher intermuscular adipose tissue index had greater risk for mortality (HR = 1.4; 95% CI, 1-1.9; P = .04).

“These chest CT-derived markers of body composition may have an added predictive value for adverse clinical outcomes such as all-cause mortality in patients with COPD,” the researchers wrote. “Although we were able to show the associations between soft-tissue markers and mortality in COPD, future studies with larger sample sizes are required to confirm these findings.”

Nicola Sverzellati, MD, PhD, professor in diagnostic imaging and chairman of the radiology unit in the department of medicine and surgery and radiology lead for imaging of chest disorders at the University of Parma, Italy, and Filippo Cademartiri, MD, PhD, chairman of the radiology department for the NHS Hospital of Urbino and senior research consultant for the Scientific Institute in Naples, Italy, discussed the findings in a related editorial.

“The study by Pishgar et al encourages the assessment of body composition for other chronic complex disorders in which alterations in either muscular or adipose tissue may be associated with pulmonary disease,” they wrote. “... Chest CT has the potential to become a powerful tool in the quest for personalized medicine in COPD. Whether it is incorporated into routine assessment for patients with COPD will ultimately depend on our ability to demonstrate that this information changes treatment and improves outcomes.”

Reference:

Sverzellati N, et al. Radiology. 2021;doi:10.1148/radiol.2021204737.