Effects of Paralyzed, Nonparalyzed, and Whole-Body Phase Angle on Physical Performance in Older Patients with Stroke

Objectives

This study investigated the association between phase angle (PhA) and physical performance in older patients with stroke, focusing on lower-limb PhA and predicting rehabilitation outcomes.

Design

A retrospective cohort study.

Setting and Participants

Seventy-one patients with stroke aged ≥65 years at a Japanese rehabilitation hospital.

Methods

Bioelectrical impedance analysis was used to measure whole-body PhA, paralyzed side lower-limb PhA, and nonparalyzed side lower-limb PhA. Physical performance was assessed using the Short Physical Performance Battery (SPPB) test at admission and discharge, with subdomains including balance, gait speed, and chair-rise performance. Multiple regression analysis was performed to determine whether different PhAs affected SPPB scores at discharge after adjusting for various potential confounders.

Results

Higher nonparalyzed side lower-limb PhA were significantly associated with better SPPB scores at discharge (β = 0.313, P = .004), and improved balance (β = 0.281, P = .016) and chair-rise performance (β = 0.388, P = .004). Paralyzed side lower-limb PhA was a predictor of total SPPB (β = 0.290, P = .020), but nonparalyzed side lower-limb PhA was more associated with total SPPB. Whole-body PhA was not associated with either total SPPB or any of the SPPB subitems.

Conclusions and Implications

Lower-limb PhA, particularly on the nonparalyzed side, is a significant predictor of physical performance in older patients with stroke. Paralyzed side lower-limb PhA plays a role, particularly in predicting walking ability. These findings suggest that site-specific PhA may represent valuable biomarkers for rehabilitation planning and prognostic assessment in patients recovering from subacute stroke events.