PP461 - BMI-ADJUSTED CALF AND MID-UPPER ARM CIRCUMFERENCE ARE ASSOCIATED WITH LENGTH OF STAY AND MORTALITY IN HOSPITALIZED NEUROLOGICAL PATIENTS DESPITE LOW CONCORDANCE

PP461

BMI-ADJUSTED CALF AND MID-UPPER ARM CIRCUMFERENCE ARE ASSOCIATED WITH LENGTH OF STAY AND MORTALITY IN HOSPITALIZED NEUROLOGICAL PATIENTS DESPITE LOW CONCORDANCE

G. Alvarado-Luis^1,*, C. Mimiaga-Hernandez¹

¹Nutrition support team, Instituto Nacional de Neurología y Neurocirugía “Manuel Velasco Suárez”, Ciudad de México, Mexico

Rationale: Patients with neurological disorders are at risk of low muscle mass (MM). Simple anthropometric measures are especially relevant in resource-limited settings. This study evaluated the association of calf circumference (CC) and mid-upper arm circumference (MUAC) adjusted for body mass index (BMI) with length of stay (LOS) and in-hospital mortality.

Methods: A retrospective cohort of adults admitted to a tertiary hospital in Mexico City between 2019 and 2025 was analyzed. CC and MUAC were measured within 48 hours of admission using a non-elastic tape. Adjustment factors for BMI and previously established cutoff points for the Mexican-American population at moderate and severe levels were used. Linear and Cox regression models were adjusted for sex, age, diagnosis, and comorbidities.

Results: A total of 10,610 patients were included; the most frequent diagnoses were brain tumors (31.0%), stroke (18.3%), and neuromuscular diseases (6.4%). Mean BMI was 26.5 ± 5.1 kg/m², and 53.7% were women. Low CC was identified in 55.3% and low MUAC in 26.2%; agreement was low (κ = 0.276, p < 0.001), with only 21.3% of patients classified as low by both. Severely low MUAC was associated with longer LOS (β 2.6 days; 95% CI 1.86–3.37, p < 0.001), as was moderate and severely low CC (β 3.4 days; 95% CI 2.79–3.93, p < 0.001). Mortality risk increased only in patients with severely low MUAC (HR 1.44; 95% CI 1.14–1.81, p = 0.002) and CC (HR 1.67; 95% CI 1.36–2.06, p = 0.002). The strongest association was observed when both were severely low (HR 1.87; 95% CI 1.41–2.48, p = 0.001; β 4.4 days; 95% CI 3.45–5.28, p < 0.001).

Conclusion: CC and BMI-adjusted MUAC showed low concordance but were independently associated with LOS and mortality. Their combined use may improve nutritional risk identification in hospitalized neurological patients.

Disclosure of Interest: None declared