Sixty-day unplanned readmissions after robot-assisted versus open-radical prostatectomy.

Abstract

244 Background: Options for clinically localized prostate cancer include radical prostatectomy, radiation therapy and active surveillance. Robot-assisted radical prostatectomy (RARP) is increasingly being used, and now accounts for the majority of radical prostatectomies performed in the United States. The aim of our study was to evaluate differences in the patient population undergoing open versus robot-assisted prostatectomy, and to compare 60-day readmissions after index hospitalization for radical prostatectomy. Methods: We utilized the Nationwide Readmission database (NRD) to obtain data on patients with prostate cancer admitted in 2016 and 2017 for radical prostatectomy in the United States. We used T-test to compare means of continuous variables and chi-square test to compare proportions of categorical variables. Multivariable logistic regression was used evaluate risk factors for 60-day unplanned readmissions. Results: A total of 115,551 patients met the inclusion criteria, of which 80.1% underwent RARP. Patients undergoing RARP were slightly older (64.8 vs 63.1 years, p < 0.0001), more likely to have private insurance (51.7% vs 44.3%, p < 0.0001) and undergo surgery at a teaching hospital (83% vs 74.6%, p < 0.0001). Importantly, open prostatectomy (OP) patients had higher rates of co-morbidities, including, hypertension, diabetes mellitus, chronic kidney disease, obstructive lung disease, heart failure, coronary artery disease and malnutrition (p < 0.01 for these co-morbidities). Hospital stay was longer in those who underwent OP (3.1 vs 1.7 days, p < 0.0001), and they were more likely to be discharged to nursing facility (3.0% vs 0.4%, p < 0.0001) or with home health care (10.9% vs 4.8%, p < 0.0001). Hospitalization charges were higher in the RARP population ($60k vs 57k, p = 0.04). Inpatient mortality was low in both groups (0.3% for OP and ~0% for RARP, p < 0.001). 60-day readmission rate was higher in those who underwent OP (9.3% vs 5.0%, p > 0.0001). Overall, the three leading causes for readmission included sepsis (10.6%), post-procedure infection (8.4%) and venous thromboembolism (VTE, 8.3%). Even after adjustment for age and comorbidities, those who underwent OP had higher risk of all-cause readmission (aOR 1.39, 95% CI 1.25-1.53, p < 0.001) and readmissions for sepsis (aOR 1.36, 95% CI 1.02-1.81, p = 0.03) and post-procedure infection (aOR 1.38, 95% CI 1.06-1.81, p = 0.02). Risk of readmission for VTE was similar in both groups. Conclusions: Nationwide, there are differences in demographics and comorbid illness burden in prostate cancer patients selected for open and robot-assisted radical prostatectomy. Better short-term outcomes in the RARP cohort may be partially attributed to lower comorbidity burden in this group. However, despite adjustment for comorbidities, higher risk for all-cause readmissions and readmissions for infectious complications persisted in the OP group.