Preoperative Frailty as a Risk Factor of Adverse Outcomes After Knee Arthroplasty: A Systematic Review and...

As the aging population increases, the demand for knee arthroplasty (KA), identifying modifiable risk factors for adverse outcomes, is critical. This study aims to evaluate whether preoperative frailty is an independent risk factor for adverse outcomes following KA.

Systematic review and meta-analysis.

We conducted a comprehensive literature search across eight electronic databases from their inception to July 1, 2024, to identify eligible studies. We included retrospective cohort studies that reported preoperative frailty and postoperative adverse outcomes following KA in adult populations aged 18 years or older. Data synthesis and meta-analysis were performed using RevMan 5.4 (Cochrane) and Stata 15.1 (StataCorp LLC, College Station, Texas). Pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated to estimate the association between preoperative frailty and postoperative complications. To explore potential sources of heterogeneity, we conducted meta-regression, subgroup analyses, and sensitivity analyses.

A total of 16 studies, encompassing 2,041,118 patients, were included in the meta-analysis. The pooled results demonstrated that preoperative frailty was significantly associated with an increased risk of postoperative complications (OR = 1.87, 95% CI: 1.53 to 2.28; P < .01), 30-day readmission (OR = 1.72, 95% CI: 1.43 to 2.05; P < .01), 30-day mortality (OR = 2.57, 95% CI: 1.82 to 3.61; P < .01), and reoperation (OR = 1.59, 95% CI: 1.23 to 2.04; P < .01). Meta-regression analyses revealed that the type of frailty assessment tool significantly contributed to heterogeneity in the associations between preoperative frailty and both postoperative complications and readmission. Subgroup analyses indicated that studies published after 2020 reported a higher magnitude of risk for adverse outcomes following KA in frail patients compared with those published before 2020. Furthermore, studies that used the age-adjusted modified frailty index to define preoperative frailty were associated with a greater risk of adverse outcomes. Preoperative frailty was consistently associated with a significantly higher risk of readmission and mortality in both primary and revision KA.

Frailty should be part of the routine preoperative assessment of KA to optimize surgical decision-making and reduce the risk of adverse health outcomes.