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Maximal Exercise Testing Variables and 10-Year Survival: Fitness Risk Score Derivation From the FIT Project



      To determine which routinely collected exercise test variables most strongly correlate with survival and to derive a fitness risk score that can be used to predict 10-year survival.

      Patients and Methods

      This was a retrospective cohort study of 58,020 adults aged 18 to 96 years who were free of established heart disease and were referred for an exercise stress test from January 1, 1991, through May 31, 2009. Demographic, clinical, exercise, and mortality data were collected on all patients as part of the Henry Ford ExercIse Testing (FIT) Project. Cox proportional hazards models were used to identify exercise test variables most predictive of survival. A “FIT Treadmill Score” was then derived from the β coefficients of the model with the highest survival discrimination.


      The median age of the 58,020 participants was 53 years (interquartile range, 45-62 years), and 28,201 (49%) were female. Over a median of 10 years (interquartile range, 8-14 years), 6456 patients (11%) died. After age and sex, peak metabolic equivalents of task and percentage of maximum predicted heart rate achieved were most highly predictive of survival (P<.001). Subsequent addition of baseline blood pressure and heart rate, change in vital signs, double product, and risk factor data did not further improve survival discrimination. The FIT Treadmill Score, calculated as [percentage of maximum predicted heart rate + 12(metabolic equivalents of task) – 4(age) + 43 if female], ranged from −200 to 200 across the cohort, was near normally distributed, and was found to be highly predictive of 10-year survival (Harrell C statistic, 0.811).


      The FIT Treadmill Score is easily attainable from any standard exercise test and translates basic treadmill performance measures into a fitness-related mortality risk score. The FIT Treadmill Score should be validated in external populations.

      Abbreviations and Acronyms:

      BP (blood pressure), CAD (coronary artery disease), CVD (cardiovascular disease), DTS (Duke Treadmill Score), FIT (Henry Ford Exercise Testing), HFHS (Henry Ford Health System), HR (heart rate), IQR (interquartile range), METs (metabolic equivalents of task), MPHR (maximum predicted heart rate), %MPHR (percentage of MPHR)
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        • Lee D.C.
        • Sui X.
        • Artero E.G.
        • et al.
        Long-term effects of changes in cardiorespiratory fitness and body mass index on all-cause and cardiovascular disease mortality in men: the Aerobics Center Longitudinal Study.
        Circulation. 2011; 124: 2483-2490
        • Ahmed H.M.
        • Blaha M.J.
        • Nasir K.
        • et al.
        Low-risk lifestyle, coronary calcium, cardiovascular events, and mortality: results from MESA.
        Am J Epidemiol. 2013; 178: 12-21
        • Berry J.D.
        • Willis B.
        • Gupta S.
        • et al.
        Lifetime risks for cardiovascular disease mortality by cardiorespiratory fitness levels measured at ages 45, 55, and 65 years in men: the Cooper Center Longitudinal Study.
        J Am Coll Cardiol. 2011; 57: 1604-1610
        • Mora S.
        • Redberg R.F.
        • Cui Y.
        • et al.
        Ability of exercise testing to predict cardiovascular and all-cause death in asymptomatic women: a 20-year follow-up of the Lipid Research Clinics Prevalence Study.
        JAMA. 2003; 290: 1600-1607
        • Nes B.M.
        • Vatten L.J.
        • Nauman J.
        • Janszky I.
        • Wisløff U.
        A simple nonexercise model of cardiorespiratory fitness predicts long-term mortality.
        Med Sci Sports Exerc. 2014; 46: 1159-1165
        • Ahmed H.M.
        • Blaha M.J.
        • Nasir K.
        • Rivera J.J.
        • Blumenthal R.S.
        Effects of physical activity on cardiovascular disease.
        Am J Cardiol. 2012; 109: 288-295
        • Whelton S.P.
        • Chin A.
        • Xin X.
        • He J.
        Effect of aerobic exercise on blood pressure: a meta-analysis of randomized, controlled trials.
        Ann Intern Med. 2002; 136: 493-503
        • Duncan J.J.
        • Farr J.E.
        • Upton S.J.
        • Hagan R.D.
        • Oglesby M.E.
        • Blair S.N.
        The effects of aerobic exercise on plasma catecholamines and blood pressure in patients with mild essential hypertension.
        JAMA. 1985; 254: 2609-2613
        • Goto C.
        • Higashi Y.
        • Kimura M.
        • et al.
        Effect of different intensities of exercise on endothelium-dependent vasodilation in humans: role of endothelium-dependent nitric oxide and oxidative stress.
        Circulation. 2003; 108: 530-535
        • Ortega F.B.
        • Lee D.C.
        • Katzmarzyk P.T.
        • et al.
        The intriguing metabolically healthy but obese phenotype: cardiovascular prognosis and role of fitness.
        Eur Heart J. 2013; 34: 389-397
        • Chodzko-Zajko W.J.
        • Proctor D.N.
        • Fiatarone Singh M.A.
        • et al.
        American College of Sports Medicine. American College of Sports Medicine Position Stand: exercise and physical activity for older adults.
        Med Sci Sports Exerc. 2009; 41: 1510-1530
        • Jensen M.T.
        • Suadicani P.
        • Hein H.O.
        • Gyntelberg F.
        Elevated resting heart rate, physical fitness and all-cause mortality: a 16-year follow-up in the Copenhagen Male Study.
        Heart. 2013; 99: 882-887
        • Skretteberg P.T.
        • Grundvold I.
        • Kjeldsen S.E.
        • et al.
        Seven-year increase in exercise systolic blood pressure at moderate workload predicts long-term risk of coronary heart disease and mortality in healthy middle-aged men.
        Hypertension. 2013; 61: 1134-1140
        • Shaw L.J.
        • Peterson E.D.
        • Shaw L.K.
        • et al.
        Use of a prognostic treadmill score in identifying diagnostic coronary disease subgroups.
        Circulation. 1998; 98: 1622-1630
        • Mark D.B.
        • Shaw L.
        • Harrell Jr., F.E.
        • et al.
        Prognostic value of a treadmill exercise score in outpatients with suspected coronary artery disease.
        N Engl J Med. 1991; 325: 849-853
        • Al-Mallah M.H.
        • Keteyian S.J.
        • Brawner C.A.
        • Whelton S.
        • Blaha M.J.
        Rationale and design of the Henry Ford Exercise Testing Project (the FIT Project).
        Clin Cardiol. 2014; 37: 456-461
        • Bruce R.A.
        • Pearson R.
        • Lovejoy Jr., F.W.
        • Yu P.N.G.
        • Brothers G.B.
        Variability of respiratory and circulatory performance during standardized exercise.
        J Clin Invest. 1949; 28: 1431-1438
        • Gibbons R.J.
        • Balady G.J.
        • Bricker J.T.
        • et al.
        ACC/AHA 2002 guideline update for exercise testing: summary article; a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Update the 1997 Exercise Testing Guidelines).
        J Am Coll Cardiol. 2002; 40: 1531-1540
        • Wilson P.W.
        • D’Agostino R.B.
        • Levy D.
        • Belanger A.M.
        • Silbershatz H.
        • Kannel W.B.
        Prediction of coronary heart disease using risk factor categories.
        Circulation. 1998; 97: 1837-1847
        • Harrell Jr., F.E.
        • Califf R.M.
        • Pryor D.B.
        • Lee K.L.
        • Rosati R.A.
        Evaluating the yield of medical tests.
        JAMA. 1982; 247: 2543-2546
        • Newson R.B.
        Comparing the predictive powers of survival models using Harrell's C or Somer's D.
        STATA J. 2010; 10: 339-358
        • Gage B.F.
        • van Walraven C.
        • Pearce L.
        • et al.
        Selecting patients with atrial fibrillation for anticoagulation: stroke risk stratification in patients taking aspirin.
        Circulation. 2004; 110: 2287-2292
        • Eagle K.A.
        • Lim M.J.
        • Dabbous O.H.
        • et al.
        • GRACE Investigators
        A validated prediction model for all forms of acute coronary syndrome: estimating the risk of 6-month postdischarge death in an international registry.
        JAMA. 2004; 291: 2727-2733
        • Antman E.M.
        • Cohen M.
        • Bernink P.J.
        • et al.
        The TIMI risk score for unstable angina/non-ST elevation MI: a method for prognostication and therapeutic decision making.
        JAMA. 2000; 284: 835-842
        • Blair S.N.
        • Kohl III, H.W.
        • Barlow C.E.
        • Paffenbarger Jr., R.S.
        • Gibbons L.W.
        • Macera C.A.
        Changes in physical fitness and all-cause mortality: a prospective study of healthy and unhealthy men.
        JAMA. 1995; 273: 1093-1098
        • Blair S.N.
        • Kohl III, H.W.
        • Paffenbarger Jr., R.S.
        • Clark D.G.
        • Cooper K.H.
        • Gibbons L.W.
        Physical fitness and all-cause mortality: a prospective study of healthy men and women.
        JAMA. 1989; 262: 2395-2401
        • Ekelund L.-G.
        • Haskell W.L.
        • Johnson J.L.
        • Whaley F.S.
        • Criqui M.H.
        • Sheps D.S.
        Lipid Research Clinics Mortality Follow-up Study. Physical fitness as a predictor of cardiovascular mortality in asymptomatic North American men.
        N Engl J Med. 1988; 319: 1379-1384
        • Myers J.
        • Prakash V.
        • Froelicher D.
        • Do D.
        • Partington S.
        • Atwood J.E.
        Exercise capacity and mortality among men referred for exercise testing.
        N Engl J Med. 2002; 346: 793-801
        • Kodama S.
        • Saito K.
        • Tanaka S.
        • et al.
        Cardiorespiratory fitness as a quantitative predictor of all-cause mortality and cardiovascular events in healthy men and women: a meta-analysis.
        JAMA. 2009; 301: 2024-2035
        • Gulati M.
        • Pandey D.K.
        • Arnsdorf M.F.
        • et al.
        Exercise capacity and the risk of death in women: the St James Women Take Heart Project.
        Circulation. 2003; 108: 1554-1559
        • Stevens J.
        • Cai J.
        • Evenson K.R.
        • Thomas R.
        Fitness and fatness as predictors of mortality from all causes and from cardiovascular disease in men and women in the Lipid Research Clinics Study.
        Am J Epidemiol. 2002; 156: 832-841
        • Hein H.O.
        • Suadicani P.
        • Gyntelberg F.
        Physical fitness or physical activity as a predictor of ischemic heart disease? a 17-year follow-up in the Copenhagen Male Study.
        J Intern Med. 1992; 232: 471-479
        • Balady G.J.
        • Larson M.G.
        • Vasan R.S.
        • Leip E.P.
        • O'Donnell C.J.
        • Levy D.
        Usefulness of exercise testing in the prediction of coronary disease risk among asymptomatic persons as a function of the Framingham risk score.
        Circulation. 2004; 110: 1920-1925
        • Wickramasinghe C.D.
        • Ayers C.R.
        • Das S.
        • de Lemos J.A.
        • Willis B.L.
        • Berry J.D.
        Prediction of 30-year risk for cardiovascular mortality by fitness and risk factor levels: the Cooper Center Longitudinal Study.
        Circ Cardiovasc Qual Outcomes. 2014; 7: 597-602
        • Fleisher L.A.
        • Beckman J.A.
        • Brown K.A.
        • et al.
        ACC/AHA guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery): developed in collaboration with the American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, and Society for Vascular Surgery.
        Circulation. 2007; 116 ([published corrections appear in Circulation. 2008;117(5):e154 and Circulation. 2008;118(9):e143-e144]): e418-e499
        • Leeper N.J.
        • Dewey F.E.
        • Ashley E.A.
        • et al.
        Prognostic value of heart rate increase at onset of exercise testing.
        Circulation. 2007; 115: 468-474
        • La Rovere M.T.
        • Bigger Jr., J.T.
        • Marcus F.I.
        • Mortara A.
        • Schwartz P.J.
        ATRAMI (Autonomic Tone and Reflexes After Myocardial Infarction) Investigators. Baroreflex sensitivity and heart-rate variability in prediction of total cardiac mortality after myocardial infarction.
        Lancet. 1998; 351: 478-484
        • Ellestad M.H.
        Chronotropic incompetence: the implications of heart rate response to exercise (compensatory parasympathetic hyperactivity?).
        Circulation. 1996; 93: 1485-1487
        • Gulati M.
        • Shaw L.J.
        • Thisted R.A.
        • Black H.R.
        • Bairey Merz C.N.
        • Arnsdorf M.F.
        Heart rate response to exercise stress testing in asymptomatic women: the St James Women Take Heart Project.
        Circulation. 2010; 122: 130-137
        • McTiernan A.
        • Wu L.
        • Chen C.
        • et al.
        • Women's Health Initiative Investigators
        Relation of BMI and physical activity to sex hormones in postmenopausal women.
        Obesity (Silver Spring). 2006; 14: 1662-1677
        • Bertone-Johnson E.R.
        • Tworoger S.S.
        • Hankinson S.E.
        Recreational physical activity and steroid hormone levels in postmenopausal women.
        Am J Epidemiol. 2009; 170: 1095-1104
        • Chan M.F.
        • Dowsett M.
        • Folkerd E.
        • et al.
        Usual physical activity and endogenous sex hormones in postmenopausal women: the European Prospective Investigation into Cancer–Norfolk population study.
        Cancer Epidemiol Biomarkers Prev. 2007; 16: 900-905
        • Aoyagi Y.
        • Shephard R.J.
        Sex differences in relationships between habitual physical activity and health in the elderly: practical implications for epidemiologists based on pedometer/accelerometer data from the Nakanojo Study.
        Arch Gerontol Geriatr. 2013; 56: 327-338
      1. United Nations, Department of Economic and Social Affairs. World Population Prospects: The 2012 Revision. United Nations website. Published 2012. Updated April 14, 2014. Accessed October 1, 2013.

        • Candore G.
        • Balistreri R.C.
        • Colonna-Romano G.
        • et al.
        Gender-related immune-inflammatory factors, age-related diseases, and longevity.
        Rejuvenation Res. 2010; 13: 292-297
        • Pan Z.
        • Chang C.
        Gender and the regulation of longevity: implications for autoimmunity.
        Autoimmun Rev. 2012; 11: A393-A403
        • Lai S.
        • Kaykha A.
        • Yamazaki T.
        • et al.
        Treadmill scores in elderly men.
        J Am Coll Cardiol. 2004; 43: 606-615
        • Prakash M.
        • Myers J.
        • Froelicher V.F.
        • et al.
        Clinical and exercise test predictors of all-cause mortality: results from >6,000 consecutive referred male patients.
        Chest. 2001; 120: 1003-1013
        • Gulati M.
        • Arnsdorf M.F.
        • Shaw L.J.
        • et al.
        Prognostic value of the Duke Treadmill Score in asymptomatic women.
        Am J Cardiol. 2005; 96: 369-375