Investigating Fat Fraction in Gluteus and Psoas Muscles Among Smokers and Non-Smokers in the German National Cohort (NAKO)

Motivation: Understanding muscle composition and its relationship with demographic and lifestyle factors is essential for maintaining health and preventing disease. Goal(s): To obtain insights into how age, gender, and smoking habits impact gluteus and psoas muscle fat fraction. Approach: A U-Net was trained to automatically segment the psoas and gluteus muscle regions from 27'805 whole-body T1W Dixon MRI (NAKO cohort). Fat fractions were calculated from the segmented muscle regions in the fat and water image. The resulting fat fractions are compared to the age, gender and smoking habits using NAKO metadata. Results: MR-derived gluteus and psoas fat fractions correlate with age and smoking status. Impact: This study demonstrates that automated fat fraction quantification in gluteus and psoas muscle groups from MRI reveals significant increases with age and higher muscle fat content in smokers. These insights may inspire new research into muscle health interventions.