title: The impact of frailty on outcomes after cardiac surgery: a systematic review.
abstract: OBJECTIVE
  Current preoperative assessments for cardiac surgery, such as the European System for Cardiac Operative Risk Evaluation II and the Society of Thoracic Surgeons risk score, are limited in their ability to predict postoperative outcomes. This is thought to be due to the reliance on chronological age as a predictor of health. In geriatrics, frailty assessments have been developed as a tool in determining physiologic functioning capacity. Whether or not frailty predicts postoperative outcomes independent of existing cardiac preoperative risk scores remains unknown.
  
  
  METHODS
  We performed a systematic review to determine the association of frailty with negative postoperative outcomes such as major adverse cardiac and cerebrovascular events (MACCE) in patients undergoing cardiac surgery. We searched PubMed, EMBASE, the Cochrane library, and Ageline from inception until July 2013 and screened 5913 abstracts for potential inclusion. Of these, 6 studies examined the relationship between objective frailty assessments and postoperative outcomes. Our included studies evaluated 4756 patients undergoing cardiac surgery.
  
  
  RESULTS
  Frailty, defined using multiple criteria, had a strong positive relationship with the risk of MACCE (odds ratio, 4.89; 95% confidence interval, 1.64-14.60). Relationships were stronger in older patients undergoing transcatheter aortic valve replacement (TAVR) than younger patients undergoing coronary artery bypass grafting and valvular surgery (hazard ratio for frailty in TAVR, 3.31-4.89 vs hazard ratio for non-TAVR, 1.10-3.16).
  
  
  CONCLUSIONS
  Patients deemed frail, determined using an objective assessment tool, have a higher likelihood of experiencing mortality, morbidity, functional decline, and MACCE following cardiac surgery, regardless of definition. Further study is needed to determine which components of frailty are most predictive of negative postoperative outcomes before integration in risk prediction scores.
authors.affiliation: Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Aresh
authors.initials: A
authors.lastname: Sepehri
authors.affiliation: School of Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Beggs
authors.affiliation: Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Ansar
authors.initials: A
authors.lastname: Hassan
authors.affiliation: Renal Program, Seven Oaks General Hospital, Winnipeg, Manitoba, Canada; Section of Nephrology, Department of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Claudio
authors.initials: C
authors.lastname: Rigatto
authors.affiliation: St Boniface General Hospital, Winnipeg, Manitoba, Canada.
authors.forename: Christine
authors.initials: C
authors.lastname: Shaw-Daigle
authors.affiliation: Renal Program, Seven Oaks General Hospital, Winnipeg, Manitoba, Canada; Section of Nephrology, Department of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Navdeep
authors.initials: N
authors.lastname: Tangri
authors.affiliation: University of Manitoba Health Sciences Libraries, Winnipeg, Manitoba, Canada. Electronic address: rakeshcarora@gmail.com.
authors.forename: Rakesh C
authors.initials: RC
authors.lastname: Arora
mesh_terms: D000203:Activities of Daily Living; D000367:Age Factors; D000368:Aged; D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000401:mortality; D003661:Decision Support Techniques; D016330:Frail Elderly; D015577:Geriatric Assessment; D006801:Humans; D008875:Middle Aged; D016017:Odds Ratio; D018579:Patient Selection; D011183:Postoperative Complications / Q000209:etiology* / Q000401:mortality; D018570:Risk Assessment; D012307:Risk Factors; D016896:Treatment Outcome