Adipose tissue may be a modifiable risk factor for ILD

Greater pericardial and abdominal visceral adipose tissue on CT scan was associated with early interstitial lung abnormalities and lower FVC in a study of community-dwelling adults, researchers reported in Chest.

“We know that people with obesity have lower lung function and a faster rate in decline of lung function over time,” Michaela R. Anderson, MD, MS, from the department of medicine at the Columbia University Medical Center, told Healio. “Our work suggests that this is not entirely due to the mechanical effects of fat tissue pushing on the chest wall and diaphragm, but rather that fat tissue may also cause actual lung injury that is detectable on CT scan.”
Researchers analyzed the Multi-Ethnic Study of Atherosclerosis (MESA), a large, multicenter, prospective cohort study of community-dwelling adults without clinically evident cardiovascular disease. Anderson and colleagues assessed CT measures of pericardial, abdominal visceral and abdominal subcutaneous adipose tissue and the association with high attenuation areas and interstitial lung abnormalities and also evaluated the association of adipose size with FVC and obesity and inflammation biomarkers.

In total, the researchers assessed data on 6,784 adults (47% men; median age, 62 years; median BMI, 27.6 kg/m²) with available measures of high attenuation area and pericardial adipose tissue volume on cardiac CT.

With every doubling in pericardial adipose tissue volume, the researchers observed a 63.4 U increase in high attenuation areas, 20% increased odds of interstitial lung abnormalities and a 5.5% decrease in percent-predicted FVC in fully adjusted models. Between pericardial adipose tissue and high attenuation areas, interleukin-6 levels accounted for 8% of the association, according to the researchers.

Michaela R. Anderson, MD, MS

With every doubling in visceral adipose tissue area, the researchers observed a 41.5 U increase in high attenuation areas, 30% increased odds of interstitial lung abnormalities and a 5.4% decrease in percent-predicted FVC. Between visceral adipose tissue and high attenuation areas, interleukin-6 and leptin levels accounted for 17% and 18%, respectively, of the associations.

“Quantification of adipose tissue on CT identified adiposity as a novel target for prevention of ILD and highlights the importance of the nonmechanical effects of adipose tissue on the lung,” the researchers wrote.

Anderson told Healio it is important to understand how to manage these patients and prevent additional damage to the lungs.

“We really need to better understand how fat tissue affects the lungs — this may help us identify ways to mitigate this injury,” Anderson said. “The changes that we identified on CT scan in our study are relatively subtle and patients are often asymptomatic. So, we need to learn how to manage these patients to prevent any additional lung injury and to prevent these subtle changes from turning into symptomatic lung disease.”

For more information:

Michaela R. Anderson, MD, MS, can be reached at mdr2140@cumc.columbia.edu.