Exercise intolerance at hospital discharge as a predictor for readmission and mortality after aortic aneurysm repair

Abstract

Abstract Background As procedures of aortic aneurysm repair have advanced, an increased number of surgeries performed for older patients and those with comorbidities and low activities of daily living. Conversely, since these patients frequently suffer from difficulty returning to their daily activities after the surgery, physical function is considered an important indicator for risk classification and treatment effect evaluation. However, in patients following aortic aneurysm repair, the association between physical performance and clinical outcomes is not thoroughly evaluated. Purpose We aimed to clarify whether physical function at hospital discharge predicted clinical outcomes, including readmission rates and mortality, in patients following aortic aneurysm repair. Methods This was a single-centre cohort study. We included the patients admitted to a tertiary hospital to undergo surgery or endovascular repair for aortic aneurysm and who received cardiovascular rehabilitation during hospitalisation. As patient characteristics during hospitalisation, age, sex, body mass index (BMI), urgent or standby surgery, surgical type (open repair or endovascular), and comorbidities were obtained from medical records. We also reviewed 6-minute walk distance (6MWD) as physical function at hospital discharge, and 6MWD <300 m was defined as exercise intolerance. The primary and secondary endpoints were readmission and death for all causes, respectively. The multivariate Cox regression analysis was used to examine whether exercise tolerance predicted the endpoints. Results The 365 patients were studied for analysis. Exercise intolerance was observed in 107 patients (29.3 %). During the median follow-up period of 2.3 years, readmission and mortality for all causes occurred in 161 (44.1 %) and 39 (10.7 %), respectively. After adjusting for patient characteristics, including age, sex, BMI, urgent or standby surgery, and surgical type, exercise intolerance defined by 6MWD <300 m was significantly associated with higher mortality (adjusted hazard ratio [aHR]: 2.21, 95% confidence interval [CI]: 1.05–4.66, Figure 1-A) and readmission rates (aHR: 1.63, 95% CI: 1.13–2.34, Figure 1-B). Conclusions In patients following aortic aneurysm repair, exercise intolerance at hospital discharge independently predicted readmission and death for all causes. Our findings suggest that physical function after the aortic aneurysm repair is a useful predictor for patient risk classification and an indicator for treatment effect evaluation.