Interrelationships between malnutrition, dehydration, frailty, and sarcopenia in older adults with proximal femur fractures: a prospective observational study

BACKGROUND: Proximal femur fractures (PFFs) are a hallmark of frailty in patients aged ≥ 65 years. Geriatric frailty is multifactorial, with malnutrition, dehydration, and sarcopenia negatively impacting outcomes after PFF. AIMS: The primary aim of this study was to examine the interrelationships between frailty, malnutrition, hydration status, and ultrasound-defined muscle impairment in older patients with proximal femur fracture. As a secondary objective, we explored the association of these vulnerability domains with 3-month mortality as an exploratory outcome. METHODS: In this prospective observational study, 108 consecutive patients aged ≥ 65 years undergoing surgical treatment for PFF at Cattinara Hospital (Trieste) were evaluated. Clinical, nutritional (MNA, MUST), functional (ADL, CFS, NHFS, MPI), cognitive (SPMSQ), and dehydration (CDS) assessments were performed. Ultrasound sarcopenia index (USI) measurements were obtained in both upper and lower limbs of 78 patients. RESULTS: Mean age was 85.9 ± 6.6 years. Malnutrition, clinical dehydration, and frailty were present in 2.7%, 38%, and 56% of patients, respectively. Among patients assessed by ultrasound, 39% showed sarcopenic features. Nutritional status was significantly associated with frailty, dehydration, ultrasound-defined sarcopenia, and calf circumference (p < 0.05). At univariate analysis, poorer nutritional, cognitive, and functional status, frailty, and preoperative complications were associated with higher 3-month mortality, whereas surgery within 72 h was protective. DISCUSSION: Malnutrition, dehydration, and sarcopenia frequently coexist and are closely correlated with geriatric frailty and mortality in patients aged ≥ 65 years with PFF. CONCLUSIONS: These findings support the relevance of a comprehensive orthogeriatric assessment to better characterize biological vulnerability and guide perioperative care.