Downloaded from http://heart.bmj.com/ on April 12, 2015 - Published by group.bmj.com
Editorial
Cochrane corner: exercise for people with high cardiovascular risk Pamela Serón,1 Héctor Pardo,2 Fernando Lanas1 Physical inactivity accounts for 3.3% of deaths and 19 million disability-adjusted life years worldwide.1 It has been shown that regular physical activity is a protective factor associated with myocardial infarction (OR 0.86, 95% CI 0.76 to 0.97), reducing population attributable risk by 12%.2 Physical activity during adulthood can increase total life expectancy and life expectancy free of cardiovascular disease between 1.3 and 3.5 years.3 From the point of view of primary prevention, emphasis to control cardiovascular risk factors such as hypertension, dyslipidemia and type II diabetes is fundamentally related to pharmacological interventions. As a result, measures to control underlying factors, such as diet and physical activity, are often overlooked. However, these underlying factors, given their pleiotropic effects, influence both established and emerging risk factors,4 5 making them invaluable tools for the primary prevention of cardiovascular and chronic conditions. Exercise raises highdensity lipoprotein (HDL) cholesterol; lowers low-density lipoprotein (LDL) cholesterol, triglycerides and blood pressure; improves fasting and postprandial glucoseinsulin homeostasis; maintains and induce weight loss and improves psychological well-being. It is also likely to reduce inflammation, improve endothelial function and facilitate smoking cessation.5 Another issue in the primary prevention of cardiovascular risk factors is that interventions are recommended based on individual risk factors instead of on a person’s total cardiovascular risk. Approaching the patient as a whole allows gauging the combined effect of several risk factors4 and determining the effectiveness of various interventions to control each risk factor individually and the person’s total cardiovascular risk. 1
Departament of Internal Medicine, Center of Excellence CIGES, Universidad de La Frontera, Temuco, Chile 2Iberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain Correspondence to Dr Pamela Serón, Internal Medicine Departament, CIGES, Universidad de La Frontera, Claro Solar 115—Of 304, Temuco 4781176, Chile; [email protected]
In this context, a Cochrane systematic review was conducted in order to assess the effects of exercise training on overall cardiovascular mortality, incidence of cardiovascular events and total cardiovascular risk among people with increased cardiovascular risk but who did not present a concurrent cardiovascular disease.6 This systematic review included four studies involving 823 participants, 412 in the exercise group and 411 in the control group. Follow-up of participants ranged from 16 weeks to 6 months. No study assessed cardiovascular, all-cause mortality or cardiovascular events as outcomes. Some of the studies reported total cardiovascular risk, LDL and HDL cholesterol, blood pressure, body mass index, exercise capacity and health-related quality of life. However, the available evidence was not sufficient to determine the effectiveness of exercise training on total cardiovascular risk. The main questions investigated in this review and the results for each of the reported outcomes are presented in tables 1 and 2, respectively.
Table 1
The first limitation that must be highlighted is the small number of studies that met the eligibility criteria or that assessed total cardiovascular risk. Four studies were included since it was possible for us to calculate total cardiovascular risk using the available data, and only one study assessed total cardiovascular risk as an outcome. There was also great heterogeneity of populations and interventions, which prevented us from conducting a meta-analysis and from extrapolating our findings. The second limitation is the high risk of bias associated with the included trials, especially the selection bias (due to lack of allocation concealment), detection bias (due to lack of blinding of staff and participants) and attrition bias (due to incomplete reporting of results). In addition, there were shortcomings in the report of relevant aspects of the implementation of the studies, specifically the method of allocation to interventions and the methodology used to analyse differences in outcomes. Additionally, some of the results were reported only as graphs (without actual data) that showed trends within groups but that lacked comparisons between groups. Finally, follow-up of patients was in general short, which precludes the possibility of assessing the impact of exercise on survival or on the development of cardiovascular events.
PICO summary
Population
Intervention group Control group Outcomes
LIMITATIONS OF THE EVIDENCE
People who were 18 years old or older, that had a 10-year Framingham risk score equal to or greater than 10% over 10 years, and without history of cardiovascular events (acute myocardial infarction or stroke). An alternative criteria was to include studies where were possible calculate the average 10-year Framingham risk score with data from the aggregated published data Aerobic or resistance exercise alone. Aerobic or resistance exercise in combination with any other intervention (diet, medication, etc) No exercise. Other intervention (diet, medication, etc) Primary: ▸ All-cause mortality and CVD-related mortality ▸ Incidence of acute myocardial infarction ▸ Incidence of stroke Secondary: ▸ Total CVD risk (difference of changes in the 10-year Framingham score or any other validated score). ▸ Total cholesterol. ▸ HDL and LDL cholesterol. ▸ Blood pressure. ▸ Body mass index. ▸ Smoking cessation. ▸ Exercise capacity (VO2max, calories, or metres in 6 minute walking test). ▸ Quality of life (Short Form-36 questionnaire or others). ▸ Adverse events
CVD, cardiovascular disease; HDL, high-density lipoprotein; LDL, low-density lipoprotein; PICO, population, intervention, control or comparison, outcomes; RCT, randomised clinical trial; VO2 max, maximal oxygen consumption.
Serón P, et al. Heart May 2015 Vol 101 No 9
663
Downloaded from http://heart.bmj.com/ on April 12, 2015 - Published by group.bmj.com
Editorial To cite Serón P, Pardo H, Lanas F. Heart 2015;101:663–664.
Table 2 Effects of intervention
Fukahori 1999 Hellenius 1993 Mendivil 2006 Nishijima 2007
Total CV Risk
Tot-C
LDL-C
HDL-C
SBP
DBP
BMI
Exercise capacity
HRQL
N/E N/D N/D N/D
N/D N/D N/D N/D
N/E N/D N/D N/D
↑ N/D ↑ N/D
N/E ↑ N/D ↑
N/E ↑ N/D ↑
N/D ↑ ↑ N/E
N/E N/D N/E ↑
N/E N/E N/E ↑
Note: All-cause mortality and CVD-related mortality, incidence of cardiovascular events, smoking cessation and adverse events were not reported in included studies. ↑, statistically significant differences in favour of the exercise group; BMI, body mass index; CV, cardiovascular; CVD, cardiovascular disease; DBP, diastolic blood pressure; HDL-C, high density lipoprotein cholesterol; HRQL, health-related quality of life; LDL-C, low-density lipoprotein cholesterol; N/D, no differences; N/E, no evaluated; SBP, systolic blood pressure; Tot-C, total cholesterol.
CLINICAL IMPLICATIONS Scientific evidence conducted and reported properly is a resource increasingly being used to make decisions on specific patients. In addition, scientific evidence is also suitable at the population level, when used in clinical guidelines or as part of economic analyses. Regarding prevention of cardiovascular disease, physical activity and exercise can be considered preventive and therapeutic interventions proven effective in the control of individual cardiovascular risk factors associated with type II diabetes, hypertension, dyslipidemia and obesity. In addition, they have a positive impact on preventing the development of chronic diseases and on survival. One can therefore hypothesise that physical activity and exercise should be effective decreasing total cardiovascular risk (in the hope that this effect also is multiplicative) and thus
664
reducing the chance of presenting a cardiovascular event or dying prematurely from it. Confirming this hypothesis is key to further promote physical activity or exercise training in any of its forms and dosages. Meanwhile, further research is warranted to determine the type, modality and length of training that is more effective, efficient and safe in people with increased total cardiovascular risk. Contributors PS drafted the manuscript. HP and FL revised the manuscript for its intellectual content. All authors contributed substantially to this manuscript and have approved the final version. Competing interests None.
Published Online First 25 February 2015 Heart 2015;101:663–664. doi:10.1136/heartjnl-2014-307123
REFERENCES 1
2
3
4
5
6
Bull F, Armstrong T, Dixon T, et al. Chapter 10: physical inactivity. In: Ezzati M, Lopez A, Rodgers A, Murray C, eds. Comparative quantification of health risks. Global and regional burden of disease attributable to selected major risk factors. World Health Organization, 2004;729–881. Yusuf S, Hawken S, Ounpuu S, et al. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case–control study. Lancet 2004;364:937–52. Franco OH, de Laet C, Peeters A, et al. Effects of physical activity on life expectancy with cardiovascular disease. Arch Intern Med 2005;165:2355–60. Graham I, Atar D, Borch-Johnsen K, et al. European guidelines on cardiovascular disease prevention in clinical practice: full text. Fourth Joint Task Force of the European Society of Cardiology and other societies on cardiovascular disease prevention in clinical practice (constituted by representatives of nine societies and by invited experts). Eur J Cardiovasc Prev Rehabil 2007;14(Suppl 2):S1–113. Mozaffarian D, Wilson PW, Kannel WB. Beyond established and novel risk factors: lifestyle risk factors for cardiovascular disease. Circulation 2008;117: 3031–8. Seron P, Lanas F, Pardo Hernandez H, et al. Exercise for people with high cardiovascular risk. Cochrane Database Syst Rev 2014;8:CD009387.
Provenance and peer review Commissioned; internally peer reviewed.
Serón P, et al. Heart May 2015 Vol 101 No 9
Downloaded from http://heart.bmj.com/ on April 12, 2015 - Published by group.bmj.com
Cochrane corner: exercise for people with high cardiovascular risk Pamela Serón, Héctor Pardo and Fernando Lanas Heart 2015 101: 663-664 originally published online February 25, 2015
doi: 10.1136/heartjnl-2014-307123 Updated information and services can be found at: http://heart.bmj.com/content/101/9/663
These include:
References Email alerting service
Topic Collections
This article cites 5 articles, 1 of which you can access for free at: http://heart.bmj.com/content/101/9/663#BIBL Receive free email alerts when new articles cite this article. Sign up in the box at the top right corner of the online article.
Articles on similar topics can be found in the following collections Epidemiology (3367) Drugs: cardiovascular system (8141) Hypertension (2760) Acute coronary syndromes (2551) Metabolic disorders (951) Smoking cessation (51) Tobacco use (578)
Notes
To request permissions go to: http://group.bmj.com/group/rights-licensing/permissions To order reprints go to: http://journals.bmj.com/cgi/reprintform To subscribe to BMJ go to: http://group.bmj.com/subscribe/
Editorial
Cochrane corner: exercise for people with high cardiovascular risk Pamela Serón,1 Héctor Pardo,2 Fernando Lanas1 Physical inactivity accounts for 3.3% of deaths and 19 million disability-adjusted life years worldwide.1 It has been shown that regular physical activity is a protective factor associated with myocardial infarction (OR 0.86, 95% CI 0.76 to 0.97), reducing population attributable risk by 12%.2 Physical activity during adulthood can increase total life expectancy and life expectancy free of cardiovascular disease between 1.3 and 3.5 years.3 From the point of view of primary prevention, emphasis to control cardiovascular risk factors such as hypertension, dyslipidemia and type II diabetes is fundamentally related to pharmacological interventions. As a result, measures to control underlying factors, such as diet and physical activity, are often overlooked. However, these underlying factors, given their pleiotropic effects, influence both established and emerging risk factors,4 5 making them invaluable tools for the primary prevention of cardiovascular and chronic conditions. Exercise raises highdensity lipoprotein (HDL) cholesterol; lowers low-density lipoprotein (LDL) cholesterol, triglycerides and blood pressure; improves fasting and postprandial glucoseinsulin homeostasis; maintains and induce weight loss and improves psychological well-being. It is also likely to reduce inflammation, improve endothelial function and facilitate smoking cessation.5 Another issue in the primary prevention of cardiovascular risk factors is that interventions are recommended based on individual risk factors instead of on a person’s total cardiovascular risk. Approaching the patient as a whole allows gauging the combined effect of several risk factors4 and determining the effectiveness of various interventions to control each risk factor individually and the person’s total cardiovascular risk. 1
Departament of Internal Medicine, Center of Excellence CIGES, Universidad de La Frontera, Temuco, Chile 2Iberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain Correspondence to Dr Pamela Serón, Internal Medicine Departament, CIGES, Universidad de La Frontera, Claro Solar 115—Of 304, Temuco 4781176, Chile; [email protected]
In this context, a Cochrane systematic review was conducted in order to assess the effects of exercise training on overall cardiovascular mortality, incidence of cardiovascular events and total cardiovascular risk among people with increased cardiovascular risk but who did not present a concurrent cardiovascular disease.6 This systematic review included four studies involving 823 participants, 412 in the exercise group and 411 in the control group. Follow-up of participants ranged from 16 weeks to 6 months. No study assessed cardiovascular, all-cause mortality or cardiovascular events as outcomes. Some of the studies reported total cardiovascular risk, LDL and HDL cholesterol, blood pressure, body mass index, exercise capacity and health-related quality of life. However, the available evidence was not sufficient to determine the effectiveness of exercise training on total cardiovascular risk. The main questions investigated in this review and the results for each of the reported outcomes are presented in tables 1 and 2, respectively.
Table 1
The first limitation that must be highlighted is the small number of studies that met the eligibility criteria or that assessed total cardiovascular risk. Four studies were included since it was possible for us to calculate total cardiovascular risk using the available data, and only one study assessed total cardiovascular risk as an outcome. There was also great heterogeneity of populations and interventions, which prevented us from conducting a meta-analysis and from extrapolating our findings. The second limitation is the high risk of bias associated with the included trials, especially the selection bias (due to lack of allocation concealment), detection bias (due to lack of blinding of staff and participants) and attrition bias (due to incomplete reporting of results). In addition, there were shortcomings in the report of relevant aspects of the implementation of the studies, specifically the method of allocation to interventions and the methodology used to analyse differences in outcomes. Additionally, some of the results were reported only as graphs (without actual data) that showed trends within groups but that lacked comparisons between groups. Finally, follow-up of patients was in general short, which precludes the possibility of assessing the impact of exercise on survival or on the development of cardiovascular events.
PICO summary
Population
Intervention group Control group Outcomes
LIMITATIONS OF THE EVIDENCE
People who were 18 years old or older, that had a 10-year Framingham risk score equal to or greater than 10% over 10 years, and without history of cardiovascular events (acute myocardial infarction or stroke). An alternative criteria was to include studies where were possible calculate the average 10-year Framingham risk score with data from the aggregated published data Aerobic or resistance exercise alone. Aerobic or resistance exercise in combination with any other intervention (diet, medication, etc) No exercise. Other intervention (diet, medication, etc) Primary: ▸ All-cause mortality and CVD-related mortality ▸ Incidence of acute myocardial infarction ▸ Incidence of stroke Secondary: ▸ Total CVD risk (difference of changes in the 10-year Framingham score or any other validated score). ▸ Total cholesterol. ▸ HDL and LDL cholesterol. ▸ Blood pressure. ▸ Body mass index. ▸ Smoking cessation. ▸ Exercise capacity (VO2max, calories, or metres in 6 minute walking test). ▸ Quality of life (Short Form-36 questionnaire or others). ▸ Adverse events
CVD, cardiovascular disease; HDL, high-density lipoprotein; LDL, low-density lipoprotein; PICO, population, intervention, control or comparison, outcomes; RCT, randomised clinical trial; VO2 max, maximal oxygen consumption.
Serón P, et al. Heart May 2015 Vol 101 No 9
663
Downloaded from http://heart.bmj.com/ on April 12, 2015 - Published by group.bmj.com
Editorial To cite Serón P, Pardo H, Lanas F. Heart 2015;101:663–664.
Table 2 Effects of intervention
Fukahori 1999 Hellenius 1993 Mendivil 2006 Nishijima 2007
Total CV Risk
Tot-C
LDL-C
HDL-C
SBP
DBP
BMI
Exercise capacity
HRQL
N/E N/D N/D N/D
N/D N/D N/D N/D
N/E N/D N/D N/D
↑ N/D ↑ N/D
N/E ↑ N/D ↑
N/E ↑ N/D ↑
N/D ↑ ↑ N/E
N/E N/D N/E ↑
N/E N/E N/E ↑
Note: All-cause mortality and CVD-related mortality, incidence of cardiovascular events, smoking cessation and adverse events were not reported in included studies. ↑, statistically significant differences in favour of the exercise group; BMI, body mass index; CV, cardiovascular; CVD, cardiovascular disease; DBP, diastolic blood pressure; HDL-C, high density lipoprotein cholesterol; HRQL, health-related quality of life; LDL-C, low-density lipoprotein cholesterol; N/D, no differences; N/E, no evaluated; SBP, systolic blood pressure; Tot-C, total cholesterol.
CLINICAL IMPLICATIONS Scientific evidence conducted and reported properly is a resource increasingly being used to make decisions on specific patients. In addition, scientific evidence is also suitable at the population level, when used in clinical guidelines or as part of economic analyses. Regarding prevention of cardiovascular disease, physical activity and exercise can be considered preventive and therapeutic interventions proven effective in the control of individual cardiovascular risk factors associated with type II diabetes, hypertension, dyslipidemia and obesity. In addition, they have a positive impact on preventing the development of chronic diseases and on survival. One can therefore hypothesise that physical activity and exercise should be effective decreasing total cardiovascular risk (in the hope that this effect also is multiplicative) and thus
664
reducing the chance of presenting a cardiovascular event or dying prematurely from it. Confirming this hypothesis is key to further promote physical activity or exercise training in any of its forms and dosages. Meanwhile, further research is warranted to determine the type, modality and length of training that is more effective, efficient and safe in people with increased total cardiovascular risk. Contributors PS drafted the manuscript. HP and FL revised the manuscript for its intellectual content. All authors contributed substantially to this manuscript and have approved the final version. Competing interests None.
Published Online First 25 February 2015 Heart 2015;101:663–664. doi:10.1136/heartjnl-2014-307123
REFERENCES 1
2
3
4
5
6
Bull F, Armstrong T, Dixon T, et al. Chapter 10: physical inactivity. In: Ezzati M, Lopez A, Rodgers A, Murray C, eds. Comparative quantification of health risks. Global and regional burden of disease attributable to selected major risk factors. World Health Organization, 2004;729–881. Yusuf S, Hawken S, Ounpuu S, et al. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case–control study. Lancet 2004;364:937–52. Franco OH, de Laet C, Peeters A, et al. Effects of physical activity on life expectancy with cardiovascular disease. Arch Intern Med 2005;165:2355–60. Graham I, Atar D, Borch-Johnsen K, et al. European guidelines on cardiovascular disease prevention in clinical practice: full text. Fourth Joint Task Force of the European Society of Cardiology and other societies on cardiovascular disease prevention in clinical practice (constituted by representatives of nine societies and by invited experts). Eur J Cardiovasc Prev Rehabil 2007;14(Suppl 2):S1–113. Mozaffarian D, Wilson PW, Kannel WB. Beyond established and novel risk factors: lifestyle risk factors for cardiovascular disease. Circulation 2008;117: 3031–8. Seron P, Lanas F, Pardo Hernandez H, et al. Exercise for people with high cardiovascular risk. Cochrane Database Syst Rev 2014;8:CD009387.
Provenance and peer review Commissioned; internally peer reviewed.
Serón P, et al. Heart May 2015 Vol 101 No 9
Downloaded from http://heart.bmj.com/ on April 12, 2015 - Published by group.bmj.com
Cochrane corner: exercise for people with high cardiovascular risk Pamela Serón, Héctor Pardo and Fernando Lanas Heart 2015 101: 663-664 originally published online February 25, 2015
doi: 10.1136/heartjnl-2014-307123 Updated information and services can be found at: http://heart.bmj.com/content/101/9/663
These include:
References Email alerting service
Topic Collections
This article cites 5 articles, 1 of which you can access for free at: http://heart.bmj.com/content/101/9/663#BIBL Receive free email alerts when new articles cite this article. Sign up in the box at the top right corner of the online article.
Articles on similar topics can be found in the following collections Epidemiology (3367) Drugs: cardiovascular system (8141) Hypertension (2760) Acute coronary syndromes (2551) Metabolic disorders (951) Smoking cessation (51) Tobacco use (578)
Notes
To request permissions go to: http://group.bmj.com/group/rights-licensing/permissions To order reprints go to: http://journals.bmj.com/cgi/reprintform To subscribe to BMJ go to: http://group.bmj.com/subscribe/
