Retrospective Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Apr 26, 2018; 10(4): 26-34
Published online Apr 26, 2018. doi: 10.4330/wjc.v10.i4.26
Preventive fraction of physical fitness on risk factors in cardiac patients: Retrospective epidemiological study
Maxime Caru, Laurence Kern, Marc Bousquet, Daniel Curnier
Maxime Caru, Laurence Kern, Department of Science and Technology of Physical Activities and Sports, University Paris Nanterre, Nanterre 92000, France
Maxime Caru, Daniel Curnier, Department of Kinesiology, University of Montreal, Montreal H2X 0A9, Canada
Marc Bousquet, Clinic of Saint-Orens, Cardiovascular and Pulmonary Rehabilitation Center, Saint-Orens-de-Gameville 31650, France
Daniel Curnier, University of Montreal Hospital Research Center, Montreal H2X 0A9, Canada
Author contributions: Caru M and Curnier D wrote the manuscript; Kern L, Bousquet M and Curnier D reviewed and validated the final version of the manuscript; Caru M, Bousquet M and Curnier D designed the study; Bousquet M and Curnier D co-ordinated and provided the collection of data; Caru M and Kern L performed the statistical analyses.
Institutional review board statement: The study was reviewed and approved by the clinic of Saint Orens according to the rules of the country. Institutional Review Board, law n°2004-806; August 9, 2004.
Informed consent statement: All participants, and this investigation was conducted in accordance to the World Medical Association Declaration of Helsinki, and depended on country rules (law n°2004-806; August 9th 2004). Also, the analysis used clinical data without storage of patient identifiers that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: The Authors declares that there is no conflict of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Daniel Curnier, PhD, Professor, Research Scientist, Laboratoire de Physiopathologie de l’EXercice, Department of Kinesiology, University of Montreal, CEPSUM, 2100, boulevard Édouard Montpetit, Montreal H2X 0A9, Canada. daniel.curnier@umontreal.ca
Telephone: +1-514-3435942
Received: January 18, 2018
Peer-review started: January 18, 2018
First decision: January 31, 2018
Revised: March 15, 2018
Accepted: April 1, 2018
Article in press: April 1, 2018
Published online: April 26, 2018
Processing time: 98 Days and 8.5 Hours
ARTICLE HIGHLIGHTS
Research background

Cardiovascular diseases (CVDs) remain the main cause of death in the world with about 17.5 million deaths. CVDs are usually associated with a high level of risk factors. The practice of physical activity has benefits on the risk factors, however, we do not know the preventive action of physical fitness on the risk factors in patients who have developed CVDs. Thus, this study aims to quantify the preventive fraction of physical fitness on the risk factors in patients with CVDs.

Research motivation

The effect of physical fitness on the risk factors in patients who have developed a cardiovascular disease remains an open question. Regular physical activity is a practice accessible to all patients with CVDs, but it may be difficult to adhere to an aerobic-based exercise program, due to external constraints.

Research objectives

Quantifying the preventive fraction of physical fitness on the risk factors in patients with CVDs is very important. The aggregate role of physical fitness in the development of cardiovascular risk factors needs to be better documented. Our work provides new insights on this research field.

Research methods

A total of 249 subjects (205 men and 44 women) suffering from a CVD were categorized into four groups, according to their percentage of physical fitness. The physical fitness of subjects was evaluated from an exercise stress test on an ergocycle. We calculated the odds ratio to obtain the preventive fraction in order to evaluate the impact of the physical fitness level on the risk factors (i.e., abdominal obesity, depression, diabetes, dyslipidemia, hypertension, obesity, overweight and smoking). The preventive fraction is a ratio used in epidemiological studies to assess the impact of an exposure factor (physical fitness) on a disease (risk factors). It is an important evaluation tool that allows knowing the preventive action of the physical fitness levels on the risk factors studied.

Research results

It is observed that a normal physical fitness level is sufficient to induce a preventive action on abdominal obesity (38%), diabetes (12%), hypertension (33%), obesity (12%) and overweight (11%). Also, the preventive fraction increases with the level of physical fitness, in particular for hypertension (36%) and overweight (16%). A high physical fitness level does not necessarily induce a preventive action in most risk factors, excluding depression. Our study suggests that even if the recommendations of ACSM (allowing to reach 100% of the theoretical physical fitness) are not met, a normal physical fitness level, even 20% below the predicted fitness, is enough to reduce some of the risk factors studied.

Research conclusions

This study demonstrates that a normal physical fitness level induces a preventive action for most risk factors studied. A high level of physical fitness does not necessarily lead to a better preventive fraction. CVDs remain the main cause of death in the world with about 17.5 million deaths. It is observed that almost half of the deaths in Europe are attributable to CVDs, touching approximately 1.9 million men and 2.2 million women. The development of different risk factors (i.e., abdominal obesity, depression, diabetes, dyslipidemia, hypertension, obesity, overweight, smoking) and physical inactivity promote CVDs. The practice of physical activities allows to decrease the risk of CVDs and has a protective role against metabolic risk factors.

Research perspectives

There is evidence of an inverse relationship between the physical activity and CVDs; our study reinforces these statements. However, it may be difficult to adhere to an aerobic-based exercise program, due to external constraints. Our study suggests that a normal physical fitness level, even 20% below the predicted fitness, is enough to reduce some of the risk factors studied. The practice of physical activity should be maintained throughout life to preserve these training effects. The future research should include the pharmacological treatments.