Heart Failure: Causes and Risk Factors
Heart failure may be due to a variety of factors and causes, such as damage to the heart muscle of unknown origin (idiopathic cardiomyopathy), developmental abnormalities (eg, atrial septal defect), thyroid disease (eg, hyperthyroidism), and cardiac valve disease, among others. The most common cause of heart failure is ischemic heart disease due to coronary artery atherosclerosis. Recognition and mitigation of the various contributing factors may reduce heart failure risk and improve prognosis.27,28
Genetics and Family History
A family history of heart failure, cardiomyopathy (dysfunction of heart muscle), atherosclerotic disease, arrhythmia, skeletal myopathy (muscle disease involving skeletal muscle), or sudden cardiac death are well-known risk factors for heart failure.28-30
Diet and Lifestyle
Dietary and lifestyle factors associated with increased risk of heart failure include excessive alcohol consumption and nutritional deficiencies (B vitamins).30-32 Smoking is a major risk factor for developing heart failure, and quitting smoking was shown to have a significant effect on lowering morbidity and the risk of death in people with left ventricular dysfunction, an effect that was comparable to currently approved drugs.33,34
Physical inactivity, a known risk factor for many cardiovascular diseases, was shown to worsen the survival rate of patients with heart failure; a study reported that 2.5 years after being admitted to the hospital, only 25% of patients with a sedentary lifestyle were alive compared with 75% of physically active patients.35
Insufficient intake of fruits and vegetables is another risk factor associated with heart failure. A 22-year, prospective cohort study including 20,900 men assessed the association between heart failure and body weight, smoking, exercise, alcohol intake, and dietary habits, including fruit, vegetable, and breakfast cereal consumption. Healthy lifestyle habits were individually and jointly linked to a lower lifetime risk of heart failure, with the lowest risk (1 in 10) in the men who adhered to four or more factors, and the highest risk (1 in 5) in the men who adhered to none of the six factors.36 In addition, a diet with too much added sugar has been shown to increase risk of cardiovascular disease and mortality.37
Health Conditions Associated with Heart Failure
Heart disease. Atrial fibrillation, valve disease (mitral regurgitation), ischemic heart disease due to coronary artery atherosclerosis, and prior heart attack are associated with an increased risk of heart failure.30,38 Heart arrhythmias; cardiomyopathy caused by drug use, disease, infection, or alcohol abuse; and myocarditis from an infection may also cause heart disease. In addition, congenital heart defects may lead to heart failure.1
Hypertension. Hypertension (high blood pressure) increases heart failure risk two- to three-fold.39,40 Half of patients with acute heart failure have systolic blood pressure over 140 mmHg, and 70% have a history of high blood pressure.41 For more information, refer to the High Blood Pressure protocol.
Diabetes. Diabetics have a high rate of heart failure, and their heart failure prognosis is usually worse than in non-diabetics.42 Diabetics often have elevated lipid levels and hypertension, both risk factors for heart failure.
Chronic obstructive pulmonary disease (COPD). Long-standing obstructive pulmonary disease, often caused by tobacco abuse, is associated with heart failure, and when the two occur simultaneously, prognosis is worse than either alone.43 Advanced COPD typically contributes to right-sided heart failure (cor pulmonale).
Renal insufficiency/kidney disease. Heart failure can reduce blood flow to the kidneys, which may cause kidney failure if untreated. Evidence suggests heart failure is widespread in patients with chronic kidney disease and end-stage renal disease, and its prevalence increases with decreasing kidney function. Heart diseases is a strong predictor of mortality in dialysis patients.44
Overweight/obesity. The heart of an obese person must work harder than for a non-obese person. Having a high body mass index (BMI) is a risk factor for developing heart failure.45 Being overweight is linked to heart failure risk factors such as high blood pressure, diabetes, high blood lipid levels, metabolic syndrome, and an enlarged left ventricle. Obesity is also associated with sleep apnea and cardiomyopathy.19
Depression. Depression and heart failure often occur together, especially in older people. These conditions also seem to worsen one another in older individuals, a phenomenon termed “negative synergism.” Depression is often under-recognized in heart failure patients. Proper mental health screening and support is an important part of optimal care for those affected by heart failure.46 More information is available in Life Extension’s Depression protocol.
Other conditions. Other conditions less well-recognized to be linked with increased heart failure risk include iron overload, rheumatologic and connective tissue disorders, infection (HIV, infectious myocarditis), endocrine disorders (thyroid disease and growth hormone disorders), and amyloidosis and sarcoidosis.47
Obstructive Sleep Apnea—A Hidden Epidemic with Deadly Consequences
Obstructive sleep apnea, a common and potentially lethal sleep disorder, results from the upper airway collapsing during sleep, reducing oxygen flow. The resulting low oxygen in the bloodstream arouses the individual, resulting in disrupted sleep. Between 2% and 7% of adults have obstructive sleep apnea, causing signs and symptoms including intractable fatigue and sleepiness during the day, frequent loud snoring, long periods without breathing (known as apnea events, observed by another person), and poor concentration.48,49 Research suggests 30‒50% of heart failure patients have sleep apnea, which contributes to the progression of heart failure and associated morbidity and mortality.50
This underdiagnosed and often overlooked sleep disorder represents a major risk factor for cardiovascular disease, including hypertension, coronary artery disease, cardiac arrhythmias, sudden cardiac death, and heart failure.51 Obstructive sleep apnea has been associated with a 68% increase in coronary heart disease in men.52
One theory suggests sleep apnea generates oxidative stress, inflammation, and endothelial dysfunction, which further cardiovascular issues.50 Obstructive sleep apnea may also be associated with increased cholesterol levels and increased rates of hypertension,53,54 type 2 diabetes,55 cancer mortality,56 stroke, and death.57
More information is available in the Sleep Apnea protocol.
Medications That May Increase Heart Failure Risk
Certain medications may cause or worsen heart failure through toxicity, worsening hypertension levels, increasing the sodium load, or drug-drug interactions.58 Some drugs that cause or exacerbate heart failure include58:
- thiazolidinediones (a class of diabetes medications)
- antiarrhythmics (eg, dronedarone)
- anti-cancer drugs (eg, anthracyclines)
- targeted cancer therapies (eg, bevacizumab and lapatinib)
- hematologic medications (eg, anagrelide)
- certain antidepressants (eg, citalopram)
- pergolide (an anti-Parkinson medication)
- certain appetite suppressants
- pulmonary medications (eg, bosentan and epoprostenol)
- tumor necrosis factor-alpha (TNF-α) inhibitors
Predictors of poor outcome and mortality in heart failure include having a reduced VO2 max capacity (the maximum intake of oxygen with increasing exercise intensity), older age, male gender, diabetes, a left ventricular ejection fraction of <45%, and a more advanced New York Heart Association (NYHA) heart failure classification.22 Anemia and depression have also been associated with poor outcomes in heart failure.59,60
Complications of Heart Failure
The prognosis of heart failure depends on the patient’s age and overall health, as well as the cause and severity of heart failure. Complications may include liver or kidney damage or failure, problems with the heart valves or heart rhythm, pulmonary congestion, anemia, muscle wasting, stroke, or pulmonary embolism. While there is no cure for heart failure, some people may experience improvements in heart function and symptoms with proper treatment, including medications, weight loss, exercise, a healthy diet, stress reduction, and dietary supplements, such as CoQ10, fish oil, and carnitine.1