MRI reveals link between hidden muscle fat and undiagnosed cardiometabolic risk
A specialized algorithm is giving experts a better understanding of how hidden muscle fat on imaging affects cardiometabolic health.
New findings published in Radiology suggest that intramuscular fat is associated with high blood pressure and unhealthy lipid and blood sugar levels. Researchers used a segmentation model to quantify how the amount of this type of fat affects overall health risks and whether proactive assessments could improve long-term cardiovascular outcomes.
“Skeletal muscle is a major driver of metabolic health, influencing cardiovascular outcomes through multiple pathways, including glucose regulation, energy metabolism and inflammatory responses, all of which influence cardiovascular health outcomes,” said lead researcher Sebastian Ziegelmayer, MD, an associate professor and attending radiologist at Technical University of Munich.
Previously, quantifying the relationship between adipose tissue and healthy, functional muscle tissue was an arduous, time-consuming manual process. Specially trained segmentation algorithms slash the amount of time it takes to analyze data from imaging, offering physicians detailed information that can be used to better predict patients’ risks.
Recently, experts applied deep learning to the imaging of more than 11,000 healthy patients to compare how different levels of intramuscular fat impact markers of cardiometabolic health, such as cholesterol, hypertension and blood sugar. Whole-body MRI exams scans were performed, with researchers paying close attention to paraspinal muscles that span from the neck to the pelvis.
The team observed an inverse relationship between intramuscular fat, lean muscle mass and cardiometabolic risk factors. Higher levels of intramuscular fat increased with age, whereas lean muscle mass decreased, especially in women; this finding was associated with lower levels of self-reported physical activity as well. After adjusting for age, sex and study location, researchers determined that higher levels of intramuscular fat increased the likelihood of hypertension, atherogenic dyslipidemia and dysglycemia in both sexes, while lean muscle decreased the odds of these diagnoses.
Prior to the exams, the patients had not been diagnosed with any type of preexisting condition, but findings from the scans indicated that many patients had significant cardiometabolic risk factors. After the scans, labs and clinical assessments, however, around 16% were diagnosed with hypertension; abnormal blood sugar levels were brought to the attention of another 8% and high cholesterol was diagnosed in 46%.
“We focused on a healthy population with no known prior disease, and yet we found quite substantial cardiometabolic risk factors in these participants,” Ziegelmayer said. “We found that the higher the intermuscular fat and the lower the muscle mass, the greater the cardiometabolic risk factors.”
Read more, including how the team foresees this sort of data being used in opportunistic healthcare in the future, here.
In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She began covering the medical imaging industry for Innovate Healthcare in 2021.