Frailty for Perioperative Clinicians: A Narrative Review

Daniel I. McIsaac, MD, MPH, FRCPC; David B. MacDonald, MD, FRCPC; Sylvie D. Aucoin, MD, MSc, FRCPC


Anesth Analg. 2020;130(6):1450-1460. 

In This Article

The Prevalence of Frailty Before Surgery

Risk factors may be considered important for prognostication and care planning for a variety of reasons.[21] Typically, one would consider a risk factor to have particular importance if (1) the risk factor is prevalent, (2) the risk factor is strongly predictive of outcome (eg, >50% relative risk increase), and/or (3) if the risk factor is potentially modifiable.[22] Below, we discuss the expected prevalence of frailty in surgical patients, while subsequent sections will address the strength of association and possible modifiability of frailty.

In the general (ie, nonsurgical) population, frailty prevalence increases exponentially with age. At age 65 years, prevalence is typically <10%, while above age 85 years, prevalence typically exceeds 50%.[23] The prevalence of frailty in surgical populations differs substantially from the general population and is the product of several considerations. First, the prevalence of frailty is highly influenced by the instrument used to assess frailty (as well as the threshold used to define frailty when applying the instrument). For example, the frailty defining diagnosis approach (where the presence of one or more of a set of diagnoses typically associated with adverse aging is used to define frailty[24,25]) tends to estimate a relatively low prevalence (<10% in elective surgery[15]), whereas multidimensional clinical frailty assessments (eg, Fried Phenotype [FP], Clinical Frailty Scale [CFS]) tend to estimate a prevalence of 30%–40%.[26] The type and urgency of surgery is also an important predictor of prevalence. For example, prevalence of frailty in prostatectomy is much lower than cystectomy,[27] as surgically amenable prostate cancer has lower symptom burden than bladder cancer and prostatectomy is typically only considered for individuals with prolonged expected survival. Frailty prevalence also tends to be higher for emergency (versus elective) procedures. For example, a population-based study of major emergency surgery reported an 8-fold higher prevalence of frailty than a similar study of major elective surgery that used the same frailty definition and data source.[15,28] Overall, age-stratified prevalence of frailty is higher in surgical populations compared to community-based samples. Using a clinically assessed multidimensional frailty instrument in the elective setting (where average age approximates 70 years), one would expect to identify frailty in approximately 30% of patients presenting for nononcologic surgery,[29] with prevalence approaching 50% in cancer surgery.[30] In a similarly aged community-based sample, frailty prevalence would approximate 10%–15%.[31] Higher prevalence and severity can be expected in emergency settings.