Cardiovascular disease refers to any disease that affects the cardiovascular system, principally cardiac disease, vascular diseases of the brain and kidney, and peripheral arterial disease.
The causes of cardiovascular disease are diverse but atherosclerosis and/or hypertension are the most common.
In addition, with aging come a number of physiological and morphological changes that alter cardiovascular function and lead to increased risk of cardiovascular disease, even in healthy asymptomatic individuals.
Cardiovascular disease is the leading cause of deaths worldwide, though, since the 1970s, cardiovascular mortality rates have declined in many high-income countries.
At the same time, cardiovascular deaths and disease have increased at a fast rate in low- and middle-income countries.
Although cardiovascular disease usually affects older adults, the antecedents of cardiovascular disease, notably atherosclerosis, begin in early life, making primary prevention efforts necessary from childhood.
There is therefore increased emphasis on preventing atherosclerosis by modifying risk factors, for example by healthy eating, exercise, and avoidance of smoking tobacco.
There is also evidence that a Mediterranean diet may be more effective than a low-fat diet in bringing about long-term changes to cardiovascular risk factors (e.g., lower cholesterol level and blood pressure).
The DASH diet (high in nuts, fish, fruits and vegetables, and low in sweets, red meat and fat) has been shown to reduce blood pressure, lower total and low density lipoprotein cholesterol and improve metabolic syndrome; but the long term benefits outside the context of a clinical trial have been questioned. A high fiber diet appears to lower the risk.
Total fat intake does not appear to be an important risk factor. A diet high in trans fatty acids; however, does appear to increase rates of cardiovascular disease.
Worldwide, dietary guidelines recommend a reduction in saturated fat. However, there are some questions around the effect of saturated fat on cardiovascular disease in the medical literature.
A 2014 review did not find evidence of harm from saturated fats. A 2012 Cochrane review found suggestive evidence of a small benefit from replacing dietary saturated fat by unsaturated fat.
A 2013 meta analysis concludes that substitution with omega 6 linoleic acid (a type of unsaturated fat) may increase cardiovascular risk.
Replacement of saturated fats with carbohydrates does not change or may increase risk.
Benefits from replacement with polyunsaturated fat appears greatest however supplementation with omega-3 fatty acids (a type of polysaturated fat) does not appear have an effect.
The effect of a low-salt diet is unclear. A Cochrane review concluded that any benefit in either hypertensive or normal-tensive people is small if present.
In addition, the review suggested that a low-salt diet may be harmful in those with congestive heart failure.
However, the review was criticized in particular for not excluding a trial in heart failure where people had low-salt and -water levels due to diuretics.
When this study is left out, the rest of the trials show a trend to benefit. Another review of dietary salt concluded that there is strong evidence that high dietary salt intake increases blood pressure and worsens hypertension, and that it increases the number of cardiovascular disease events; the latter happen both through the increased blood pressure and, quite likely, through other mechanisms.
Moderate evidence was found that high salt intake increases cardiovascular mortality; and some evidence was found for an increase in overall mortality, strokes, and left-ventricular hypertrophy.
Mineral supplements have also not been found to be useful. Niacin, a type of vitamin B3, may be an exception with a modest decrease in the risk of cardiovascular events in those at high risk. Magnesium supplementation lowers high blood pressure in a dose dependent manner.
Magnesium therapy is recommended for patients with ventricular arrhythmia associated with torsade de pointes who present with long QT syndrome as well as for the treatment of patients with digoxin intoxication-induced arrhythmias. Evidence to support omega-3 fatty acid supplementation is lacking.
Statins are effective in preventing further cardiovascular disease in people with a history of cardiovascular disease.
As the event rate is higher in men than in women, the decrease in events is more easily seen in men than women.
In those without cardiovascular disease but risk factors statins appear to also be beneficial with a decrease in mortality and further heart disease.
The time course over which statins provide prevention against death appears to be long, of the order of one year, which is much longer than the duration of their effect on lipids.
The causes of cardiovascular disease are diverse but atherosclerosis and/or hypertension are the most common.
In addition, with aging come a number of physiological and morphological changes that alter cardiovascular function and lead to increased risk of cardiovascular disease, even in healthy asymptomatic individuals.
Cardiovascular disease is the leading cause of deaths worldwide, though, since the 1970s, cardiovascular mortality rates have declined in many high-income countries.
At the same time, cardiovascular deaths and disease have increased at a fast rate in low- and middle-income countries.
Although cardiovascular disease usually affects older adults, the antecedents of cardiovascular disease, notably atherosclerosis, begin in early life, making primary prevention efforts necessary from childhood.
There is therefore increased emphasis on preventing atherosclerosis by modifying risk factors, for example by healthy eating, exercise, and avoidance of smoking tobacco.
Prevention
Currently practiced measures to prevent cardiovascular disease include:- A low-fat, high-fiber diet including whole grains and fruit and vegetables. Five portions a day reduces risk by about 25%.
- Tobacco cessation and avoidance of second-hand smoke
- Limit alcohol consumption to the recommended daily limits consumption of 1-2 standard alcoholic drinks per day may reduce risk by 30% However excessive alcohol intake increases the risk of cardiovascular disease.
- Lower blood pressures, if elevated) if overweight or obese
- Increase daily activity to 30 minutes of vigorous exercise per day at least five times per week (multiply by three if horizontal);
- Reduce sugar consumptions
- Decrease psychosocial stress. Stress however plays a relatively minor role in hypertension (if it even plays any role in the development of hypertension at all is often disputed). Specific relaxation therapies are not supported by the evidence.
Diet
A diet high in fruits and vegetables decreases the risk of cardiovascular disease and death.Evidence suggests that the Mediterranean diet may improve cardiovascular outcomes.This may be by about 30% in those at high risk.There is also evidence that a Mediterranean diet may be more effective than a low-fat diet in bringing about long-term changes to cardiovascular risk factors (e.g., lower cholesterol level and blood pressure).
The DASH diet (high in nuts, fish, fruits and vegetables, and low in sweets, red meat and fat) has been shown to reduce blood pressure, lower total and low density lipoprotein cholesterol and improve metabolic syndrome; but the long term benefits outside the context of a clinical trial have been questioned. A high fiber diet appears to lower the risk.
Total fat intake does not appear to be an important risk factor. A diet high in trans fatty acids; however, does appear to increase rates of cardiovascular disease.
Worldwide, dietary guidelines recommend a reduction in saturated fat. However, there are some questions around the effect of saturated fat on cardiovascular disease in the medical literature.
A 2014 review did not find evidence of harm from saturated fats. A 2012 Cochrane review found suggestive evidence of a small benefit from replacing dietary saturated fat by unsaturated fat.
A 2013 meta analysis concludes that substitution with omega 6 linoleic acid (a type of unsaturated fat) may increase cardiovascular risk.
Replacement of saturated fats with carbohydrates does not change or may increase risk.
Benefits from replacement with polyunsaturated fat appears greatest however supplementation with omega-3 fatty acids (a type of polysaturated fat) does not appear have an effect.
The effect of a low-salt diet is unclear. A Cochrane review concluded that any benefit in either hypertensive or normal-tensive people is small if present.
In addition, the review suggested that a low-salt diet may be harmful in those with congestive heart failure.
However, the review was criticized in particular for not excluding a trial in heart failure where people had low-salt and -water levels due to diuretics.
When this study is left out, the rest of the trials show a trend to benefit. Another review of dietary salt concluded that there is strong evidence that high dietary salt intake increases blood pressure and worsens hypertension, and that it increases the number of cardiovascular disease events; the latter happen both through the increased blood pressure and, quite likely, through other mechanisms.
Moderate evidence was found that high salt intake increases cardiovascular mortality; and some evidence was found for an increase in overall mortality, strokes, and left-ventricular hypertrophy.
Supplements
While a healthy diet is beneficial, in general the effect of antioxidant supplementation (vitamin E, vitamin C, etc.) or vitamins has not been shown to protection against cardiovascular disease and in some cases may possibly result in harm.Mineral supplements have also not been found to be useful. Niacin, a type of vitamin B3, may be an exception with a modest decrease in the risk of cardiovascular events in those at high risk. Magnesium supplementation lowers high blood pressure in a dose dependent manner.
Magnesium therapy is recommended for patients with ventricular arrhythmia associated with torsade de pointes who present with long QT syndrome as well as for the treatment of patients with digoxin intoxication-induced arrhythmias. Evidence to support omega-3 fatty acid supplementation is lacking.
Medication
Aspirin has been found to be of benefit overall in those at low risk of heart disease as the risk of serious bleeding is equal to the benefit with respect to cardiovascular problems.Statins are effective in preventing further cardiovascular disease in people with a history of cardiovascular disease.
As the event rate is higher in men than in women, the decrease in events is more easily seen in men than women.
In those without cardiovascular disease but risk factors statins appear to also be beneficial with a decrease in mortality and further heart disease.
The time course over which statins provide prevention against death appears to be long, of the order of one year, which is much longer than the duration of their effect on lipids.
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