Association of CT-Derived Skeletal Muscle and Adipose Tissue Metrics with Frailty in Older Adults

Acad Radiol. 2024 Feb;31(2):596-604. doi: 10.1016/j.acra.2023.06.003. Epub 2023 Jul 20.

Abstract

Rationale and objectives: Tools are needed for frailty screening of older adults. Opportunistic analysis of body composition could play a role. We aim to determine whether computed tomography (CT)-derived measurements of muscle and adipose tissue are associated with frailty.

Materials and methods: Outpatients aged ≥ 55 years consecutively imaged with contrast-enhanced abdominopelvic CT over a 3-month interval were included. Frailty was determined from the electronic health record using a previously validated electronic frailty index (eFI). CT images at the level of the L3 vertebra were automatically segmented to derive muscle metrics (skeletal muscle area [SMA], skeletal muscle density [SMD], intermuscular adipose tissue [IMAT]) and adipose tissue metrics (visceral adipose tissue [VAT], subcutaneous adipose tissue [SAT]). Distributions of demographic and CT-derived variables were compared between sexes. Sex-specific associations of muscle and adipose tissue metrics with eFI were characterized by linear regressions adjusted for age, race, ethnicity, duration between imaging and eFI measurements, and imaging parameters.

Results: The cohort comprised 886 patients (449 women, 437 men, mean age 67.9 years), of whom 382 (43%) met the criteria for pre-frailty (ie, 0.10 < eFI ≤ 0.21) and 138 (16%) for frailty (eFI > 0.21). In men, 1 standard deviation changes in SMD (β = -0.01, 95% confidence interval [CI], -0.02 to -0.001, P = .02) and VAT area (β = 0.008, 95% CI, 0.0005-0.02, P = .04), but not SMA, IMAT, or SAT, were associated with higher frailty. In women, none of the CT-derived muscle or adipose tissue metrics were associated with frailty.

Conclusion: We observed a positive association between frailty and CT-derived biomarkers of myosteatosis and visceral adiposity in a sex-dependent manner.

Keywords: Adipose tissue; Aging; Body composition; Frailty; Myopenia; Myosteatosis; Sarcopenia.

MeSH terms

  • Adipose Tissue / diagnostic imaging
  • Aged
  • Body Composition / physiology
  • Female
  • Frailty* / diagnostic imaging
  • Humans
  • Male
  • Muscle, Skeletal / diagnostic imaging
  • Tomography, X-Ray Computed