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The ACE Equation Gives Equivalent Mortality Risk Estimates to the Duke Treadmill Score and Duke Nomogram

Montoye, Alexander H.K. ; Fonley, Morgan R. ; Westgate, Bradford S. ; Brudin, Lars and Lindow, Thomas LU (2026) In Journal of Cardiopulmonary Rehabilitation and Prevention
Abstract

Purpose: – We sought to develop an equation, the Alma College Estimation (ACE) equation, to estimate survival equivalent to the Duke treadmill score (DTS) and Duke nomogram. Methods: – Combinations of ST segment deviation (0, 1, 2, 3, and 4 mm), angina (0 = none, 1 = nonlimiting, and 2 = limiting), and metabolic equivalents of task (2–20) were graphed on the Duke nomogram, and the ACE equation was developed to predict annual mortality likelihood from nomogram measurements. Secondary analyses analyzed data from a clinical cohort of 10, 673 patients who underwent a graded maximal exercise test at a county hospital in Sweden between 2005 and 2016. Following ACE equation development, survival estimates were compared between the equation to... (More)

Purpose: – We sought to develop an equation, the Alma College Estimation (ACE) equation, to estimate survival equivalent to the Duke treadmill score (DTS) and Duke nomogram. Methods: – Combinations of ST segment deviation (0, 1, 2, 3, and 4 mm), angina (0 = none, 1 = nonlimiting, and 2 = limiting), and metabolic equivalents of task (2–20) were graphed on the Duke nomogram, and the ACE equation was developed to predict annual mortality likelihood from nomogram measurements. Secondary analyses analyzed data from a clinical cohort of 10, 673 patients who underwent a graded maximal exercise test at a county hospital in Sweden between 2005 and 2016. Following ACE equation development, survival estimates were compared between the equation to traditional line plotting on the Duke nomogram using mean absolute error and equivalence testing. Also, 5-year survival estimates from the ACE equation, nomogram, and DTS were categorized into low, intermediate, and high risk and compared using percent agreement. Results: – The developed ACE equation is a non-linear, exponential function. The 5-year survival estimates (100 – [5 × annual mortality risk]) from the ACE equation were significantly equivalent to within 1% of the nomogram (P < .001, mean difference 0.1% ± 1.0%), with low mean absolute error (all combinations: 0.7% ± 0.7%, clinical cohort: 0.7% ± 1.0%). Percent agreement in risk categories ranged from 83% to 94%. Conclusions: – The ACE equation produced similar survival estimates to the Duke nomogram and DTS. This equation improves precision over the DTS and ease of use over the Duke nomogram, and therefore, may serve as a valuable tool for clinicians assessing prognosis from exercise test findings.

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author
; ; ; and
organization
publishing date
type
Contribution to journal
publication status
epub
keywords
Bruce treadmill test, coronary artery disease, diagnosis, mortality, treadmill test
in
Journal of Cardiopulmonary Rehabilitation and Prevention
publisher
Lippincott Williams & Wilkins
external identifiers
  • pmid:41627070
  • scopus:105029827164
ISSN
1932-7501
DOI
10.1097/HCR.0000000000001009
language
English
LU publication?
yes
id
64695c95-68f4-4b5b-9af1-38246bcfde58
date added to LUP
2026-02-27 13:36:40
date last changed
2026-02-27 13:37:21
@article{64695c95-68f4-4b5b-9af1-38246bcfde58,
  abstract     = {{<p>Purpose: – We sought to develop an equation, the Alma College Estimation (ACE) equation, to estimate survival equivalent to the Duke treadmill score (DTS) and Duke nomogram. Methods: – Combinations of ST segment deviation (0, 1, 2, 3, and 4 mm), angina (0 = none, 1 = nonlimiting, and 2 = limiting), and metabolic equivalents of task (2–20) were graphed on the Duke nomogram, and the ACE equation was developed to predict annual mortality likelihood from nomogram measurements. Secondary analyses analyzed data from a clinical cohort of 10, 673 patients who underwent a graded maximal exercise test at a county hospital in Sweden between 2005 and 2016. Following ACE equation development, survival estimates were compared between the equation to traditional line plotting on the Duke nomogram using mean absolute error and equivalence testing. Also, 5-year survival estimates from the ACE equation, nomogram, and DTS were categorized into low, intermediate, and high risk and compared using percent agreement. Results: – The developed ACE equation is a non-linear, exponential function. The 5-year survival estimates (100 – [5 × annual mortality risk]) from the ACE equation were significantly equivalent to within 1% of the nomogram (P &lt; .001, mean difference 0.1% ± 1.0%), with low mean absolute error (all combinations: 0.7% ± 0.7%, clinical cohort: 0.7% ± 1.0%). Percent agreement in risk categories ranged from 83% to 94%. Conclusions: – The ACE equation produced similar survival estimates to the Duke nomogram and DTS. This equation improves precision over the DTS and ease of use over the Duke nomogram, and therefore, may serve as a valuable tool for clinicians assessing prognosis from exercise test findings.</p>}},
  author       = {{Montoye, Alexander H.K. and Fonley, Morgan R. and Westgate, Bradford S. and Brudin, Lars and Lindow, Thomas}},
  issn         = {{1932-7501}},
  keywords     = {{Bruce treadmill test; coronary artery disease; diagnosis; mortality; treadmill test}},
  language     = {{eng}},
  publisher    = {{Lippincott Williams & Wilkins}},
  series       = {{Journal of Cardiopulmonary Rehabilitation and Prevention}},
  title        = {{The ACE Equation Gives Equivalent Mortality Risk Estimates to the Duke Treadmill Score and Duke Nomogram}},
  url          = {{http://dx.doi.org/10.1097/HCR.0000000000001009}},
  doi          = {{10.1097/HCR.0000000000001009}},
  year         = {{2026}},
}