Impact of phase angle on postoperative prognosis in patients with gastrointestinal and hepatobiliary-pancreatic cancer

Objective
Phase angle (PhA), by bioelectrical impedance analysis, has been used in patients with several diseases; however, its prognostic value in patients with gastrointestinal and hepatobiliary–pancreatic (HBP) cancer is unclear. The present study aimed to investigate the impact of PhA on postoperative short-term outcomes and long-term survival in these patients.
Research Methods & Procedures
This retrospective study reviewed data of 501 patients with gastrointestinal and HBP cancers who underwent first resection surgery and divided the data into the following groups according to the preoperative PhA quartile values by sex: high-PhA group with the highest quartile (Q4), normal-PhA group with middle quartiles (Q3 and Q2), and low-PhA group with the lowest quartile (Q1). Preoperative nutritional statuses, postoperative short-term outcomes during hospitalization, and 5-year survival between three groups were compared. Cox proportional hazard models were used to evaluate the prognostic effect of PhA.
Results
PhA positively correlated with body weight, skeletal muscle mass, and handgrip strength, and negatively correlated with age and C-reactive protein levels. The low-PhA group showed a high prevalence of malnutrition (48%) than normal-PhA (25%), and high-PhA (9%) (P < 0.001). The incidence of postoperative severe complications was 10% in all patients [14% in low-PhA, 12% in normal-PhA, and 4% in high-PhA (P = 0.018)]. The incidence of prolonged postoperative high care unit or/and intensive care unit stays was 8% in all patients [16% in low-PhA, 8% in normal-PhA, and 2% in high-PhA (P < 0.001)]. The 5-year survival rate was 74% in all patients [68% in low-PhA, 74% in normal-PhA, and 79% in high-PhA (P < 0.001)]. The multivariate analysis demonstrated that a low-PhA group was an independent risk factor for mortality (hazard ratio, 1.99; 95% confidence interval 1.05–3.90; P = 0.034).
Conclusion
PhA is a useful short-term and long-term postoperative prognostic marker for patients with gastrointestinal and HBP cancers.

© 2020. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/