New research utilising artificial intelligence suggests a compelling link between the density of chest and back muscles and a reduced risk of heart attack or premature death. A study, led by the University of Edinburgh, examined hospital scans from 1,722 patients, predominantly in their 50s, who had presented with chest pain. The findings indicate that those with greater muscle density in their torso area were less likely to experience a heart attack or die within a decade following their scan.
The researchers employed AI to analyse various aspects of the upper body, including muscle, organs, bones, and fat. A key metric was skeletal muscle attenuation – how brightly the muscle appeared on a scan. Denser muscle, containing a lower proportion of fat, reflects more X-ray beams and thus appears brighter. The study found that for every 10-point increase in scan brightness, indicating better quality, denser muscle, individuals were calculated to be 31% less likely to have a heart attack and 39% less likely to die in the 10 years after the scan.
Interestingly, the study highlighted that it was the composition and quality of the muscle, rather than its overall size, that was associated with the reduced risk. Professor Michelle Williams, senior author of the study, noted that the muscles visible in the coronary computed tomography angiogram scans primarily included back muscles, parts of the pectoral muscles, and intercostal muscles between the ribs. She expressed her personal commitment to exercise, taking up activities like cycling, planks, and Pilates, due to the study's compelling results.
Experts suspect that individuals demonstrating this 'good-quality skeletal muscle' are likely to be more physically active, leading to greater strength in their torsos. Professor Bryan Williams, Chief Scientific and Medical Officer at the British Heart Foundation, which part-funded the research, commented, "It is likely that people in this study with more dense muscle mass were more physically active and as a result may have better heart health. That is yet more evidence supporting the power of exercise."
The implications of these findings could be significant for future healthcare. Researchers suggest that routine heart scans might eventually be used to identify individuals with less dense, lower-quality muscle who could be at an elevated risk of heart attacks. Such identification could lead to targeted interventions, including encouraging increased physical activity, closer monitoring, or prioritising certain patients for preventative medications.
While the study provides strong correlational evidence, further research is needed to fully understand the intricate mechanisms by which exercise influences muscle density and its direct impact on heart health. The findings underscore the well-established benefits of regular physical activity for cardiovascular well-being, reinforcing NHS guidelines that recommend adults aim for at least 150 minutes of moderate-intensity activity per week.
Source: University of Edinburgh, British Heart Foundation