Intermuscular adipose tissue affected muscle density more than intramuscular adipose tissue content with opportunistic screening at abdominal CT

Abstract

Abstract This study aimed to determine whether intermuscular adipose tissue (IMAT) or intramuscular adipose tissue content (IMAC) has a greater effect on skeletal muscle density (SMD) and to explore the underlying mechanisms. We recruited 292 inpatients without musculoskeletal system disease, all of whom underwent abdominal CT. Muscle parameters, including skeletal muscle area (SMA), skeletal muscle index (SMI), SMD, IMAC, and IMAT, as well as fat parameters—subcutaneous fat area (SFA) and subcutaneous fat density (SFD) in the abdominal wall—were measured by two musculoskeletal radiologists using ImageJ software at the third lumbar vertebra (L3) level. One-way ANOVA with LSD (chi-square test for group comparisons where p > 0.05) or Dunnett’s T3 test (p 0.05). The findings revealed that age, IMAT, and IMAC influence SMD, with IMAT exerting the most significant impact.