Preoperative frailty based on laboratory data and postoperative health outcomes in patients undergoing coronary artery bypass graft surgery


      • High frailty levels are associated with adverse health outcomes after CABG surgery.
      • Frail patients are at high risk of postoperative readmission and extended hospital stays.
      • Lab-based frailty could capture a need for thorough frailty assessments for CABG patients.



      Frailty is associated with adverse surgical outcomes. Patients with cardiovascular diseases have many risk factors of frailty; thus, preoperative frailty evaluation is necessary to predict adverse outcomes after coronary artery bypass graft (CABG) surgery. Laboratory data based-frailty assessments are objective and not time-consuming, addressing the need for an accurate but simple frailty screening for patients awaiting CABG surgery.


      This retrospective study aimed to determine the association between laboratory based-frailty and patient health outcomes after CABG surgery.


      We evaluated 896 patients who underwent on-pump or off-pump CABG surgery between August 1, 2015 and July 31, 2020 at a tertiary hospital. The frailty index-laboratory (FI-LAB), which comprises 32 laboratory parameters and vital signs, was used for frailty assessment.


      The patients were divided into three groups according to their preoperative FI-LAB level as low (FI-LAB <0.25, 23.0%), moderate (FI-LAB ≥0.25 to ≤0.4, 54.9%), and high (FI-LAB>0.4, 22.1%) frailty groups. In the confounder-adjusted analysis, the lengths of hospital stay and intensive care unit stay were longer by 2.20 days (p=.023) and by 0.89 days (p=.009), respectively, in the high frailty group than those in the low frailty group. The odds ratio for 30-day readmission was also 2.58 times higher in the high frailty group than that in the low frailty group.


      A high preoperative FI-LAB score indicates increasing risks of adverse postoperative outcomes among CABG surgery patients. FI-LAB has potential strengths to capture the need for a more thorough frailty assessment for cardiac surgery patients.


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        • Fried L.P.
        • Ferrucci L.
        • Darer J.
        • Williamson J.D.
        • Anderson G.
        Untangling the concepts of disability, frailty, and comorbidity: implications for improved targeting and care.
        J Gerontol A Biol Sci Med Sci. 2004; 59: 255-263
        • Chen X.
        • Mao G.
        • Leng S.X.
        Frailty syndrome: an overview.
        Clin Interv Aging. 2014; 9: 433-441
        • Vermeiren S.
        • Vella-Azzopardi R.
        • Beckwée D.
        • et al.
        Frailty and the prediction of negative health outcomes: a meta-analysis.
        J Am Med Dir Assoc. 2016; 17 (2016/12/01/): 1163.e1-1163.e17
        • Robinson T.N.
        • Walston J.D.
        • Brummel N.E.
        • et al.
        Frailty for surgeons: review of a National Institute on Aging conference on frailty for specialists.
        J Am Coll Surg. 2015; 221: 1083-1092
        • Afilalo J.
        • Karunananthan S.
        • Eisenberg M.J.
        • Alexander K.P.
        • Bergman H.
        Role of frailty in patients with cardiovascular disease.
        Am J Cardiol. 2009; 103: 1616-1621
        • Afilalo J.
        • Alexander K.P.
        • Mack M.J.
        • et al.
        Frailty assessment in the cardiovascular care of older adults.
        J Am Coll Cardiol. 2014; 63: 747-762
        • Partridge J.S.
        • Harari D.
        • Dhesi J.K.
        Frailty in the older surgical patient: a review.
        Age Ageing. 2012; 41: 142-147
        • Morley J.E.
        • Vellas B.
        • van Kan G.A.
        • et al.
        Frailty consensus: a call to action.
        J Am Med Dir Assoc. 2013; 14: 392-397
        • Stewart R.
        Cardiovascular disease and frailty: what are the mechanistic links?.
        Clin Chem. 2019; 65: 80-86
        • Ruiz J.G.
        • Priyadarshni S.
        • Rahaman Z.
        • et al.
        Validation of an automatically generated screening score for frailty: the care assessment need (CAN) score.
        BMC Geriatr. 2018; 18: 106
        • Jung P.
        • Pereira M.A.
        • Hiebert B.
        • et al.
        The impact of frailty on postoperative delirium in cardiac surgery patients.
        J Thorac Cardiovasc Surg. 2015; 149 (e2): 869-875
        • Koh L.Y.
        • Hwang N.C.
        Frailty in cardiac surgery.
        J Cardiothorac Vasc Anesth. 2019; 33: 521-531
        • Sepehri A.
        • Beggs T.
        • Hassan A.
        • et al.
        The impact of frailty on outcomes after cardiac surgery: a systematic review.
        J Thorac Cardiovasc Surg. 2014; 148: 3110-3117
        • Yanagawa B.
        • Graham M.M.
        • Afilalo J.
        • Hassan A.
        • Arora R.C.
        Frailty as a risk predictor in cardiac surgery: beyond the eyeball test.
        J Thorac Cardiovasc Surg. 2019; 157: 1905-1909
        • Kim D.H.
        • Kim C.A.
        • Placide S.
        • Lipsitz L.A.
        • Marcantonio E.R.
        Preoperative frailty assessment and outcomes at 6 months or later in older adults undergoing cardiac surgical procedures: a systematic review.
        Ann Intern Med. 2016; 165: 650-660
        • Tonet E.
        • Pavasini R.
        • Biscaglia S.
        • Campo G.
        Frailty in patients admitted to hospital for acute coronary syndrome: when, how and why?.
        J Geriatr Cardiol. 2019; 16: 129-137
        • Lim A.
        • Choi J.
        • Ji H.
        • Lee H.
        Frailty assessment using routine clinical data: an integrative review.
        Arch Gerontol Geriatr. 2022; 99104612
        • Ellis H.L.
        • Wan B.
        • Yeung M.
        • et al.
        Complementing chronic frailty assessment at hospital admission with an electronic frailty index (FI-Laboratory) comprising routine blood test results.
        CMAJ. 2020; 192: E3-E8
        • Sohn B.
        • Choi J.W.
        • Hwang H.Y.
        • Jang M.J.
        • Kim K.H.
        • Kim K.B.
        Frailty index is associated with adverse outcomes after aortic valve replacement in elderly patients.
        J Korean Med Sci. 2019; 34: e205
        • Blodgett J.M.
        • Theou O.
        • Howlett S.E.
        • Rockwood K.
        A frailty index from common clinical and laboratory tests predicts increased risk of death across the life course.
        GeroScience. 2017; 39: 447-455
        • World Medical Association
        World Medical Association Declaration of Helsinki: ethical principles for medical research involving human subjects.
        JAMA. 2013; 310: 2191-2194
        • Howlett S.E.
        • Rockwood M.R.
        • Mitnitski A.
        • Rockwood K.
        Standard laboratory tests to identify older adults at increased risk of death.
        BMC Med. 2014; 12: 171
        • Jung H.Y.
        • Park B.K.
        • Shin H.S.
        • Kang Y.K.
        • Pyun S.B.
        • Paik N.J.
        Development of the Korean version of Modified Barthel Index (K-MBI): multi-center study for subjects with stroke.
        J Korean Acad Rehabil Med. 2007; 31: 283-297
        • Knaus W.A.
        • Draper E.A.
        • Wagner D.P.
        • Zimmerman J.E.
        Apache II: a severity of disease classification system.
        Crit Care Med. 1985; 13: 818-829
        • Charlson M.E.
        • Pompei P.
        • Ales K.L.
        • MacKenzie C.R.
        A new method of classifying prognostic comorbidity in longitudinal studies: development and validation.
        J Chron Dis. 1987; 40: 373-383
      1. Health Insurance Review & Assessment Service. Results of the 7th adequacy evaluation for coronary artery bypass surgery; 2021.; Accessed 13 October 2021.

        • Yu P.J.
        • Cassiere H.A.
        • Fishbein J.
        • Esposito R.A.
        • Hartman A.R.
        Outcomes of patients with prolonged Intensive Care Unit length of stay after cardiac surgery.
        J Cardiothorac Vasc Anesth. 2016; 30: 1550-1554
        • Goldfarb M.
        • Bendayan M.
        • Rudski L.G.
        • et al.
        Cost of cardiac surgery in frail compared with nonfrail older adults.
        Can J Cardiol. 2017; 33: 1020-1026
        • Lee D.H.
        • Buth K.J.
        • Martin B.J.
        • Yip A.M.
        • Hirsch G.M.
        Frail patients are at increased risk for mortality and prolonged institutional care after cardiac surgery.
        Circulation. 2010; 121: 973-978
        • Sanchis J.
        • Núñez E.
        • Ruiz V.
        • et al.
        Usefulness of clinical data and biomarkers for the identification of frailty after acute coronary syndromes.
        Can J Cardiol. 2015; 31: 1462-1468
        • Blodgett J.M.
        • Theou O.
        • Mitnitski A.
        • Howlett S.E.
        • Rockwood K.
        Associations between a laboratory frailty index and adverse health outcomes across age and sex.
        Aging Med. 2019; 2 (Milton): 11-17
        • Pugh R.J.
        • Ellison A.
        • Pye K.
        • et al.
        Feasibility and reliability of frailty assessment in the critically ill: a systematic review.
        Crit Care. 2018; 22: 49
        • Nashef S.A.
        • Roques F.
        • Sharples L.D.
        • et al.
        EuroSCORE II.
        Eur J Cardiothorac Surg. 2012; 41 (discussion 744-745): 734-744
        • O'Brien S.M.
        • Feng L.
        • He X.
        • et al.
        The society of thoracic surgeons 2018 adult cardiac surgery risk models: part 2-Statistic methods and results.
        Ann Thorac Surg. 2018; 105 (The Society of Thoracic Surgeons): 1419-1428
        • Balducci L.
        Aging, frailty, and chemotherapy.
        Cancer Control. 2007; 14: 7-12
        • Ruiz J.
        • Miller A.A.
        • Tooze J.A.
        • et al.
        Frailty assessment predicts toxicity during first cycle chemotherapy for advanced lung cancer regardless of chronologic age.
        J Geriatr Oncol. 2019; 10: 48-54
        • Waite I.
        • Deshpande R.
        • Baghai M.
        • Massey T.
        • Wendler O.
        • Greenwood S.
        Home-based preoperative rehabilitation (prehab) to improve physical function and reduce hospital length of stay for frail patients undergoing coronary artery bypass graft and valve surgery.
        J Cardiothorac Surg. 2017; 12: 91
        • Ng T.P.
        • Feng L.
        • Nyunt M.S.
        • et al.
        Nutritional, physical, cognitive, and combination interventions and frailty reversal among older adults: a randomized controlled trial.
        Am J Med. 2015; 128 (e1): 1225-1236
        • Theou O.
        • Stathokostas L.
        • Roland K.P.
        • et al.
        The effectiveness of exercise interventions for the management of frailty: a systematic review.
        J Aging Res. 2011; 2011569194
        • Nidadavolu L.S.
        • Ehrlich A.L.
        • Sieber F.E.
        • Oh E.S.
        Preoperative evaluation of the frail patient.
        Anesth Analg. 2020; 130: 1493-1503