Exploring the association between phase angle and functional capacity in patients with Parkinson’s disease

M. Fortunati,^1,2 L. Grattarola,¹ V. Quintiero,¹ M. Rubino,¹ G. D’Antona,^1,3 O. Crisafulli¹ | ¹Centro di Ricerca Interdipartimentale Attività Motorie e Sportive - Sport Medicine Centre Voghera, University of Pavia, Voghera; ²Department of Industrial Engineering, University of Tor Vergata, Rome; ³Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Italy

Assessing functional capacity is crucial for the clinical evaluation of Parkinson’s disease (PD) patients. The association between phase angle (PhA), a body composition parameter obtained with bioimpedance analysis (BIA), and functional capacity is well established in healthy individuals and various clinical cohorts, but is unexplored in PD. Five PD patients underwent BIA to assess PhA (°), and a battery of tests including 6-minute walk test (6MWT; m), handgrip strength test (HGsT; kg), and cardiopulmonary exercise test (peak oxygen consumption (V̇O₂peak); mL·kg⁻¹·min⁻¹). Correlations were evaluated between PhA and functional outcomes. PhA was positively correlated with V̇O₂peak (r=0.883, p<0.05) and 6MWT (r=0.978, p<0.01), while with HGsT showed a positive, but not significant, trend (r=0.808, p>0.05). These findings provide preliminary evidence suggesting the clinical usefulness of PhA as a potential surrogate marker of functional capacity in PD patients.