Association of phase angle with hospital-acquired functional decline in older patients undergoing cardiovascular surgery

•Phase angle is related to nutritional status in older patients undergoing cardiovascular surgery.•Phase angle is related to physical functions in this group of patients.•Phase angle is related to frailty/sarcopenia in older patients undergoing cardiovascular surgery. The aim of this study was to examine whether preoperative phase angle (PhA) measured by bioelectrical impedance analysis was associated with a hospital-acquired functional decline in older patients undergoing cardiovascular surgery. This was an observational study of prospectively collected data of 114 patients (>65 y of age) with cardiovascular disease who underwent elective cardiovascular surgery between September 2019 and August 2020. Patients were classified into tertiles based on PhA levels. Factors associated with the occurrence of hospital-acquired functional decline (postoperative recovery to preoperative physical function was not possible) were analyzed using univariate and multivariate analyses. Patients in the low PhA group were significantly older than those in the middle and high PhA groups; were predominantly women; had higher New York Heart Association cardiovascular and EuroSCORE severity scores; and had significantly lower levels of body mass index, Geriatric Nutritional Risk Index, hemoglobin, and albumin. There was a significant correlation between PhA and nutrition and physical function. The incidence of hospital-acquired functional decline occurred in 26.3% of all patients, with a significantly higher incidence in patients in the low PhA group. Multivariate analysis showed that PhA was extracted as a factor for the hospital-acquired functional decline in all the models. PhA was associated with hospital-acquired functional decline in older patients undergoing cardiovascular surgery. PhA is likely to be a comprehensive indicator of physical health that indicates nutritional status, physical function, and geriatric syndrome (frailty/sarcopenia), and is an important predictor of hospital-acquired functional decline in this group of older patients.