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Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans
Published on: October 17, 2018
Cardiorespiratory optimal point during exercise testing and sudden cardiac death: A prospective cohort study
Jari A Laukkanen1, Kai Savonen2, David Hupin3
1Institute of Clinical Medicine, Department of Medicine, University of Eastern Finland, Kuopio, Finland; Central Finland Health Care District, Department of Medicine, Jyväskylä, Finland; Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland.
The cardiorespiratory optimal point (COP) during exercise is a strong predictor of sudden cardiac death (SCD) risk. This finding suggests COP can improve long-term SCD risk prediction beyond traditional cardiovascular disease factors.
Area of Science:
- Cardiology
- Exercise Physiology
- Preventive Medicine
Background:
- Cardiorespiratory optimal point (COP) is a submaximal cardiopulmonary exercise testing (CPET) variable.
- COP may be an independent risk factor for cardiovascular disease (CVD).
- The association between COP and sudden cardiac death (SCD) risk is unknown.
Purpose of the Study:
- Evaluate the association between COP during exercise and SCD risk.
- Determine if COP improves SCD risk prediction.
Main Methods:
- COP was determined in 2190 men undergoing clinical exercise testing.
- Hazard ratios (HRs) and risk discrimination measures for SCD were calculated.
- Median follow-up was 28.8 years with 240 SCD events.
Main Results:
- COP showed a linear, dose-response association with SCD.
- Each SD increase in COP was associated with an HR of 2.51 for SCD (95% CI: 1.36-4.62).
- Adding COP to a SCD risk score improved risk prediction (C-index change: 0.0086, p=0.038).
Conclusions:
- COP during exercise is independently and inversely associated with SCD risk.
- COP may enhance long-term SCD risk prediction beyond established CVD risk factors.
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