Implementation of frailty preoperative assessment to predict outcome in patients undergoing urological surgery: a systematic review and meta-analysis

Background: A common limit of the widely used risk scores for preoperative assessment is the lack of information about aspects linked to frailty that may affect outcome, especially in the setting of elderly patients undergoing urological surgery. Frailty has recently been introduced as an additional characteristic to be assessed for better identifying patients at risk of negative outcomes. Objective: To examine the evidence for recent advances in preoperative assessment in patients undergoing urological surgery focussing on the detrimental effect of frailty on outcome, including major (mPCs) and total postoperative complications (tPCs), discharge to a facility, and mortality. The secondary aim was to establish which cut-off scores of the modified Frailty Index (mFI, 11 items) and/or simplified FI (sFI, five items) predicted PCs. Methods: We searched PubMed, the Excerpta Medica database (EMBASE), Cochrane Library and clinicaltrial.gov from inception to 31 May 2020. Studies reporting relationships between the investigated outcomes and patients’ frailty were included. We estimated odds ratios (ORs) through a random effect model by using Revman 5.4. Results: Frailty, assessed by different tools, was associated with a significantly higher rate of 30-day (OR 1.73, 95% confidence interval [CI] 1.58–1.89) and 90-day (OR 2.09, 95% CI 1.14–3.82) mPCs and 30-day tPCs (OR 2.10, 95% CI 1.76–2.52). A mFI of ≥2 was associated with a higher rate of 30-day mPCs (OR 1.79, 95% CI 1.69–1.89) and greater 30-day mortality (OR 3.46, 95% CI 2.10–5.49). A pre-planned post hoc analysis also revealed that a sFI of ≥3 was predictive of mPCs (OR 3.30, 95% CI 2.12–5.12). Conclusions: Frailty assessment may help to predict PCs and mortality in patients undergoing major urological surgery. Either a mFi of ≥2 or sFI of ≥3 should be considered potential ‘red flags’ for preoperative risk assessment and decision-making. There is not enough evidence to confirm the necessity to perform frailty assessment in minor urological surgery.