Maximal exercise testing variables and 10-year survival: fitness risk score derivation from the FIT Project
Ahmed HM, Al-Mallah MH, McEvoy JW, Nasir K, Blumenthal RS, Jones SR, Brawner CA, Keteyian SJ, Blaha MJ. Maximal exercise testing variables and 10-year survival: Fitness risk score derivation from the FIT project. Mayo Clin Proc. Mar 2015;90(3):346-355.
Mayo Clinic proceedings. Mayo Clinic
OBJECTIVE: 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.
RESULTS: 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
CONCLUSION: 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.
Medical Subject Headings
Adult; Aged; Cause of Death; Exercise Test; Female; Heart Rate; Humans; Male; Michigan; Middle Aged; Physical Fitness; Predictive Value of Tests; Prognosis; Retrospective Studies; Risk Assessment; Survival Analysis