Sarcopenia in Older Patients with Newly Diagnosed Multiple Myeloma.

<p>Introduction: Sarcopenia is an age-related condition characterised by low muscle mass and function, associated with poorer outcomes. Its prevalence and prognostic role in multiple myeloma (MM) remain unclear, as most studies only consider muscle mass defined by computed tomography (CT) scan and disregard muscle function. This study aimed to describe the prevalence of sarcopenia according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) definition in older patients with MM and to analyse its associations with other geriatric syndromes and survival outcomes. METHODS: This is a prospective study of patients aged ≥65 years with newly diagnosed MM who underwent a Comprehensive Geriatric Assessment (CGA), including handgrip strength and gait speed. Their initial positron emission tomography-computed tomography images were evaluated in terms of muscle mass, subcutaneous and visceral adipose tissue at the third lumbar vertebral level (L3). Medical records were reviewed in January 2025 to collect mortality and follow-up data. RESULTS: Of 52 patients included (55.1% women; median age 77.6 ± 5.9 years), 32 (61.5%) had probable sarcopenia (low muscle strength), and four (12.5%) had confirmed sarcopenia (low muscle strength and low muscle mass). No significant differences were found in frailty or malnutrition between sarcopenic and non-sarcopenic participants. Sarcopenic patients had significantly shorter overall survival (OS) compared with non-sarcopenic patients (43.1 vs. 18.0 months, p = 0.001), and low muscle mass was independently associated with poorer survival outcomes (hazard ratio [HR]: 46.8; 95% confidence interval [CI]: 1.9-1,146.9). In contrast, no significant differences were observed for progression-free survival (PFS), although low muscle mass remained significantly associated with an increased risk of progression (HR: 25.34; 95% CI: 1.72-374.27). CONCLUSION: This is the first study to include both muscle quantity (muscle mass) and function (muscle strength) as the correct approach for sarcopenia evaluation in older patients with MM. Patients with sarcopenia may have reduced OS, and low skeletal muscle mass index was also associated with shorter PFS, but further studies with larger cohorts are needed to confirm its prognostic value. </p>.