Bioelectrical Impedance Vector Pattern and Biomarkers of Physical Functioning of Prostate Cancer Survivors in Rehabilitation

BACKGROUND: Knowledge of clinically established factors of physical function such as body composition, bioelectrical phase angle (PhA) and handgrip strength (HGS) with mortality predictive and health-related relevance is limited in prostate cancer survivors (PCS). Therefore, the aim of this study was to characterise and compare body composition data of PCS with extensive reference data as well as to analyse PhA and HGS and the prevalence of critical prognostic values at an early stage of cancer survivorship. METHODS: One hundred and forty-eight PCS were examined at the start (T1) and end (T2) of a 3-week hospitalised urooncological rehabilitation, which began median 28 days after acute cancer therapy. Examinations included a bioimpedance analysis and HGS test. Comparison of body composition between PCS and reference data was performed using bioimpedance vector analysis (BIVA). RESULTS: BIVA of the whole PCS group showed abnormal physiology with a cachectic state and a state of overhydration/oedema, without significant changes between T1 and T2. The age- and BMI-stratified subgroup analysis showed that PCS aged 60 years and older had this abnormal pattern compared to the reference population. HGS (T1: 38.7 ± 8.9 vs T2: 40.8 ± 9.4, kg), but not PhA (T1/T2: 5.2 ± 0.7, °), changed significantly between T1 and T2. Values below a critical threshold reflecting a potentially higher risk of mortality and impaired function were found for PhA in 20% (T1) and 22% (T2) of PCS and in 41% (T1) and 29% (T2) for HGS. CONCLUSIONS: BIVA pattern and the prevalence of critically low HGS and PhA values illustrate the necessity for intensive continuation of rehabilitation and survivorship care especially in these ‘at risk’ cases. The routine assessment of body composition, PhA and HGS offer the opportunity to conduct a risk stratification for PCS and could help personalising and optimising treatment in rehabilitation and ongoing survivorship care.