What is the clinical evidence from this study?

Study design: Cohort. Population: Coronary artery disease (n=1651). Intervention: Peak oxygen uptake (V̇O2peak) vs. Lower V̇O2peak. Primary outcome: Combined MACE (all-cause mortality, acute coronary syndrome, stroke, or heart failure) (HR 0.93 (men), HR 0.95 (women) per 1 mL/kg/min increase, 95% CI 0.92-0.95 (men), 0.91-0.99 (women)).

What question did this study set out to answer?

To present sex-specific V̇O2peak reference data for cardiac rehabilitation patients and assess its association with major adverse cardiovascular events (MACE).

April 13, 2026Open Access

Sex-Specific VO2peak Reference Values and Their Association with Major Adverse Cardiovascular Events in Norwegian Cardiac Rehabilitation Patients

Key Result

Each 1 mL·kg−1·min−1 higher V̇O2peak was associated with a 7% lower MACE risk in men (HR 0.93; 95% CI 0.92-0.95) and 5% lower risk in women (HR 0.95; 95% CI 0.91-0.99) with CAD.

Key Points

To present sex-specific V̇O2peak reference data for cardiac rehabilitation patients and assess its association with major adverse cardiovascular events (MACE).
Retrospective analysis of treadmill cardiopulmonary exercise test data from 1,651 patients
Patients categorized by index event: myocardial infarction, CABG, or PCI
Generated age-, sex-, and diagnosis-specific V̇O2peak reference data
Evaluated associations of V̇O2peak with MACE using Cox proportional hazards models
Men had a higher average V̇O2peak than women (26.9 vs 23.2 mL·kg−1·min−1)
V̇O2peak decreased by 2.5 mL·kg−1·min−1 per decade in men and 1.7 in women
510 patients (36%) experienced MACE during 7,880 person-years
Higher V̇O2peak correlated with lower MACE risk: 7% in men, 5% in women per 1 mL·kg−1·min−1 increase
Patients in the highest fitness quartile had a 55% lower risk of MACE compared to the lowest quartile.

Study Design

Type

Cohort (n=1,651)

Structured PICO

Is higher V̇O2peak associated with a reduced risk of MACE in patients with CAD undergoing cardiac rehabilitation?

Population

1,651 Norwegian patients with coronary artery disease (CAD) attending inpatient cardiac rehabilitation (2004–2022), mean age 61, 21% women. Index events: myocardial infarction (MI), coronary artery bypass grafting (CABG), or percutaneous coronary intervention (PCI)/pharmacologically treated CAD.

Intervention

Peak oxygen uptake (V̇O2peak) measured by treadmill cardiopulmonary exercise test (CPET)

Outcome

Combined MACE endpoint (all-cause mortality, acute coronary syndrome, stroke, or heart failure)composite

Higher V̇O2peak is strongly associated with a lower risk of MACE in both men and women with CAD undergoing cardiac rehabilitation, supporting its use as a prognostic marker.

Main Result

Effect estimate: HR 0.93 (men), HR 0.95 (women) per 1 mL/kg/min increase (95% CI 0.92-0.95 (men), 0.91-0.99 (women))

Abstract

Abstract Aims To present sex-specific reference data for peak oxygen uptake (V̇O2peak) in Norwegian patients with coronary artery disease (CAD) undergoing cardiac rehabilitation and examine its association with major adverse cardiovascular events (MACE). Methods We retrospectively analysed treadmill cardiopulmonary exercise test (CPET) data from 1,651 CAD patients (21% women; mean (SD) age 61 (9) years) attending inpatient cardiac rehabilitation (2004–2022). Patients were categorized by index event: myocardial infarction (MI), coronary artery bypass grafting, or percutaneous coronary intervention/pharmacologically treated CAD. Age-, sex-, and diagnosis-specific V̇O2peak reference data were generated. Associations between V̇O2peak and a combined MACE endpoint (all-cause mortality, acute coronary syndrome, stroke, or heart failure) were assessed using Cox proportional hazards models including natural cubic splines for assessing non-linear patterns. Results Men had higher V̇O2peak than women (mean (SD) 26.9 (6.7) vs. 23.2 (5.3) mL·kg−1·min−1; p 0.001). V̇O2peak was on average 2.5 and 1.7 mL·kg−1·min−1 lower per decade of age in men and women, respectively. Patients with a previous MI had the highest V̇O2peak, followed by CABG and PCI/CAD (p 0.001). During 7,880 person-years, 510 patients (36%) experienced MACE. Each 1 mL·kg−1·min−1 higher V̇O2peak was associated with a 7% lower MACE risk (HR 95 % CI; 0.93 0.92-0.95) in men and 5% (HR 95 % CI; 0.95 0.91-0.99) in women. Patients in the highest cardiorespiratory fitness quartile had a 55% lower risk compared to the lowest quartile. Associations were consistent across CAD subcategories. Sex-specific natural cubic spline models revealed inverse, non-linear associations. Conclusion This study provides novel sex- and diagnosis-specific V̇O2peak reference values for Norwegian CAD patients and confirms V̇O2peak as a strong prognostic marker, supporting its integration into routine secondary prevention and individualized care.