Aims
Both sarcopenia and frailty are associated with falls in older adults. Sarcopenia is characterised by the progressive loss of skeletal muscle mass and strength, while frailty is a state of increased vulnerability to stressors due to decreased physiological reserve. Identification of individuals at risk of sarcopenia remains challenging in clinical practice. Temporalis muscle thickness (TMT), measured on T1-weighted brain magnetic resonance imaging (MRI), has been proposed as a surrogate marker for sarcopenia. This study aimed to examine whether TMT and frailty are associated with falls.
Methods
Retrospective study of participants with mild cognitive impairment/subjective cognitive concerns from the Australian Imaging, Biomarkers and Lifestyle (AIBL) Active study, an exercise intervention study, with data linked with AIBL for longitudinal follow-up. TMT was measured bilaterally, with average TMT used for analysis. Sarcopenia was defined using TMT sex-adjusted cut-offs (Males≤6.3mm, Females≤5.2mm)1. Frailty was defined using a frailty index (frail>0.25). Cox proportional hazards models examined the relationship between sarcopenia, frailty and self-reported falls over 5-years, adjusting for age and treatment allocation.
Results
91 participants (mean±standard deviation age 73.5±5.8 years, 55% female, 19% frail, TMT 7.5±1.5 mm, 9% sarcopenia). In adjusted analysis, both sarcopenia and frailty were associated with 5-year falls risk (Sarcopenia: hazard ratio (HR) 3.69, 95% CI 1.18–11.53, p=0.025; frailty: HR 3.32 95% CI 1.15 – 9.58, p=0.026).
Conclusions
TMT is a promising biomarker for identifying older adults at increased risk of falls. Its integration into clinical radiology workflows, in addition to assessing frailty, may support early intervention efforts targeting fall prevention.