Prognostic Utility of Modified 5-Item Frailty Index on the Outcomes of Spine Surgeries: A Systematic Review and Meta-analysis

Background: Frailty refers to a state of weakness that can arise due to age or illnesses, and frailty predisposes individuals to several adverse health outcomes. This has been postulated to prognosticate the outcome of various surgeries, including surgeries for various spine conditions; however, no meta-analysis has validated this finding.

Methods: We conducted a systematic review and meta-analysis to investigate the prognostic utility of frailty for the outcome of spine surgeries. We performed a systematic search of the PubMed, EMBASE, and SCOPUS databases for studies investigating the ability of frailty to predict the outcome of spine surgeries. We analyzed the effect of high frailty using the m-5FI on the outcomes (extended length of stay, readmission, postoperative complications, in-hospital mortality, reoperation, and nonroutine discharge) of spine surgeries.

Results: Meta-analysis of the information provided in the eleven studies included a sample size of 89,137; all studies used an m-5FI ≥ 2 as their cutoff for high frailty, and most studies were performed in the United States based on the ACS-NSQIP database. The outcomes of our analysis were extended hospital length of stay (LOS) (effect size 1.64; 95% confidence interval [CI]: 1.49, 1.79), postoperative complications (effect size 1.49; 95% CI: 1.10, 1.88), readmission (effect size 1.69; 95% CI: 1.40, 1.99), nonroutine discharge (effect size 2.16; 95% CI: 1.80, 2.51), postoperative in-hospital mortality (effect size 2.11; 95% CI: 1.25, 2.96), and reoperation (effect size 1.32; 95% CI: 1.19, 1.45).

Conclusion: This study revealed that high frailty according to the modified 5-Item Frailty Index is correlated with an increased risk of readmission, extended length of hospital stay, postoperative complications, nonroutine discharge, postoperative in-hospital mortality, and reoperation following spine surgeries for any pathology of the spine.