Calf circumference is associated with malnutrition risk and phase angle in subacute stroke patients

Malnutrition is common in stroke patients, emphasising the need for routine malnutrition screening. Mid-upper arm circumference (MUAC) and calf circumference (CC) are markers of muscle mass, while bioelectrical impedance analysis (BIA)-derived phase angle (PhA) is a marker of muscle quality and cellular integrity. This study investigated the relationships between limb circumferences and malnutrition risk or PhA in subacute stroke patients.

A retrospective analysis was conducted in stroke patients aged ≥50 years admitted to a rehabilitation unit. Anthropometric measurements and BIA data were collected. Malnutrition risk was assessed using the Geriatric Nutritional Risk Index (GNRI), the Prognostic Nutritional Index (PNI), and the Controlling Nutritional Status (CONUT) score. CC and MUAC cut-off values were based on sex-specific diagnostic thresholds. The study included 228 patients (age 71.7 ± 10.8 yrs, body mass index 26.8 ± 3.9 kg/m², 54% men). A high prevalence of low MUAC and CC values was observed in both sexes. High malnutrition risk was significantly more prevalent in patients with low or very low CC, whereas MUAC categories showed no significant differences. There were significant associations between CC and GNRI, PNI, and CONUT score, as well as with whole-body, upper-limb, or lower-limb PhA. By contrast, MUAC showed only weak associations with PhA.

In subacute stroke patients, CC, highly than MUAC, was associated with malnutrition risk and PhA. These findings support the use of CC as a simple measure for identifying stroke patients at higher malnutrition risk and with poorer muscle-related nutritional status.