Identifying older patients at high risk of poor outcomes after joint replacement surgery

This project recruited over 600 patients aged 65 and older going for surgery at two hospitals in Ottawa, Ontario. Frailty assessments (using two different tools) were conducted with each patient before surgery. Regular follow-ups were conducted over the first year after surgery to see how patients were doing.

About the Project

Frailty is a condition that describes the build-up of weakness across multiple body systems, and is common in elderly people. Being frail before surgery increases the risk of a bad outcome, and older patients have surgery more often than any other age group. But the problem is, clinicians don’t know what the best tool to diagnose frailty before surgery is.

To improve how elderly people recover after surgery, clinicians need to be able to identify frail people. However, we don’t know what tool is best at identifying people who are likely to have a complication after surgery.

The goal of the project was to identify differences between two leading frailty tools in their accuracy and ease of use for patients and clinicians. These new discoveries will be provided to clinicians to help them choose which frailty tool to use before surgery to identify older patients at a high-risk of bad outcomes after surgery.

Project Team

Principal Investigator:

Daniel McIsaac, MD, MPH, FRCPC — Ottawa Hospital Research Institute


Paul Beale, MD, CFPC — The Ottawa Hospital, University of Ottawa

Gregory Bryson, MD, FRCPC — The Ottawa Hospital, University of Ottawa

Alan Forster, MD, FRCPC — The Ottawa Hospital, University of Ottawa

Sylvain Gagné, MD, FRCPC — The Ottawa Hospital, University of Ottawa

Allen Huang, MD, CFPC, FRCPC — The Ottawa Hospital, University of Ottawa

John Joanisse, MD, FRCPC — Montfort Hospital

Homer Yang, MD, FRCSC — The Ottawa Hospital, University of Ottawa

Knowledge Users and Partners:

Department of Anesthesiology — University of Ottawa

Project Contact: Daniel I. McIsaac —

FRA 2015-B-06

Key words: aging; frailty; surgery; risk prediction; feasibility; disability; patient care; perioperative care; implement guidelines and best practices; improve patient outcomes


McIsaac, D., Taljaard, M., Bryson, G.L., Beaule, P.E., Gagne, S., Hamilton, G., Hladkowicz, E., Huang, A., Joanisse, J., Lavallée, L.T., Moloo, H., Thavorn, K., van Walraven, C., Yang, H., Forster, A.J. Comparative assessment of two frailty instruments for risk-stratification in elderly surgical patients: study protocol for a prospective cohort study. BMC Anesthesiology. 2016:16:111.DOI: 10.1186/s12871-016-0276-0.

Communication to Patients & Family

Key Findings:

  • One in 10 older people develop a significant new disability that impacts their day to day life three months after surgery.
  • If an older person has frailty before surgery, their odds of developing a new disability after surgery doubles.
  • For doctors who want to diagnose frailty before surgery, the Clinical Frailty Scale is an easier and faster tool than the modified Fried Index.

Why was this study was needed?

Older people have surgery more often than any other age group. Having frailty before surgery is linked to higher risks, like death and complications. But how strongly frailty is related to developing a new disability, which is a very important outcome for older people, had not been determined.

Suggestions on how these findings could impact older adults living with frailty and/or their family caregivers and how this might be measured:

  • Older people considering having surgery should ask their doctor if they have frailty.
  • If frailty is present, there is a doubling of the odds that an older person will develop a significant increase in disability after surgery.
  • Frailty was the only significant risk factor for disability that was identified in our study.

Brief comment on type of study in lay terms:

  • This was a study of people aged 65 years or older having planned surgery carried out in one of three hospitals in Ontario.
  • We recruited people before surgery, documented their health history, and did two different frailty tests.
  • We then followed people by phone for three months after surgery and measured their level of disability.
  • We assessed whether having frailty before surgery increased the odds of developing a new disability that negatively impacted people’s day to day life.
  • Having frailty meant that it was more likely that an older person having surgery would develop a new disability, stay longer in hospital, or be discharged to a nursing home.
Communication to Researchers

Key Findings:

  • Over 10% of older people who undergo elective surgery develop a new patient-reported disability after surgery.
  • The presence of frailty before surgery is associated with twice the odds of developing a new disability after surgery.
  • When compared head-to-head, the Clinical Frailty Scale and the modified Fried Index did not differ significantly in their accuracy for predicting new disability after surgery, but the Clinical Frailty Scale was faster and easier to use.

Why was this study needed?

People aged over 65 years represent most individuals having major surgery. Frailty has been consistently associated with morbidity and mortality after surgery. However, few studies evaluate the role of frailty in predicting patient-reported outcomes, such as disability, or compare the performance of different frailty instruments before surgery.

Brief overview of the methodology:

  • This was a multicenter prospective cohort study conducted in Ontario. We enrolled all adults 65 years or older having elective inpatient non-cardiac surgery. Preoperative frailty status was determined using the Clinical Frailty Scale (CFS) and the modified Fried Index (mFI). The primary outcome was a new, patient-reported disability 90 days after surgery; secondary outcomes included length of stay, discharge to an institution, hospitalization costs, and in-hospital safety incidents.
  • Of 702 patients recruited, the CFS identified frailty in 42% of participants, and the mFI 37%. Following adjustment, frailty per the CFS was significantly associated with new disability (OR 2.51, 95%CI 1.50-4.21), as was the mFI (OR 2.60, 95%CI 1.57-4.31). Sensitivity and specificity were not significantly different between tools.
  • Length of stay, costs and nursing home discharges were higher in people with frailty using either instrument. The CFS was faster and easier to use and had fewer missing data.

Potential impact of findings on clinical practice/patient care and how this impact might be measured:

  • Frailty assessment before surgery is a guideline-recommended process and may be easier and faster to do using the CFS than with the mFI.
  • Frailty is the strongest and most consistent predictor of adverse outcomes after surgery in older people, including patient-reported disability; these findings support the importance of routine frailty assessment before surgery.
  • As more than one in ten older people develop a significant disability after surgery, this risk should be discussed during the informed consent process.

Remaining knowledge/research gaps:

  • Interventions to reduce the risk of new disability after surgery, in particular among older people with frailty, should be developed and tested.
  • Although frailty is the strongest and most consistent predictor of adverse outcomes in older people having surgery, future research is needed to increase the predictive accuracy of frailty-based approaches to risk stratification.