Three common cardiovascular diseases linked to cognitive impairment and dementia risk

Three common cardiovascular diseases in adults – heart failure, atrial fibrillation and coronary artery disease – are linked to cognitive impairment and an increased risk of dementia, according to “Cardiac Contributions to Brain Health,” a new scientific statement from the American Heart Association. today in the association magazine, Myocardial infarction.

The Scientific Statement discusses the latest research on the relationship between cardiovascular health and brain health, including cognitive impairment or neuropsychological dysfunction. The statement emphasizes the interconnectedness between the brain and heart and how crucial this relationship is to overall health.

“Stroke and cognitive decline, both important determinants of brain health, are chronic and debilitating conditions that have a dramatic impact at the individual and societal levels,” said statement writing group chairman Fernando D. Testai, MD, Ph.D., FAHA, professor of neurology and rehabilitation and fellowship director of vascular neurology at the University of Illinois College of Medicine and medical director of stroke at the University of Illinois Hospital at Chicago. “Managing heart health from an early age is important to prevent cardiovascular disease and cardiac events, protect brain health, and reduce the risk of cognitive decline later in life.”

Dementia is often seen as an incurable and brutal disease that cannot be prevented. However, evidence suggests that adopting a healthy lifestyle and identifying and treating vascular risk factors early can help maintain normal brain function and reduce the burden of Alzheimer’s disease and other related dementias.”

Fernando D. Testai, MD, Ph.D., FAHA, professor of neurology and rehabilitation and fellowship director of vascular neurology, University of Illinois College of Medicine

Heart failure

Heart failure is a major public health problem, with underlying causes including hypertension, obesity, and type 2 diabetes. Heart failure is associated with cognitive impairment, which affects tasks such as self-care and medication management, especially in older adults. A meta-analysis of previous studies found that nearly 50% of people with heart failure experience some form of cognitive impairment that can affect language, memory and/or executive functions. Rates of cognitive problems tend to be higher in people with more severe forms of heart failure.

Heart failure can lead to brain damage in several ways. Decreased blood flow can cause mini-strokes or silent brain injuries. Chronic inflammation and neurohormonal activation, which maintain the brain environment, can also contribute to brain damage. Obesity and sleep-disordered breathing are common conditions in people with heart failure and are also associated with cognitive impairment. Brain changes, such as gray matter volume reduction and/or white matter damage, are common in heart failure and contribute to impaired brain function. Emerging evidence also indicates that people with heart failure and people with neurodegenerative diseases such as Alzheimer’s disease may share genetic variations.

For patients with severe heart failure, cognitive screening before surgical intervention is advised due to the increased risk of stroke; Stroke is known to be one of the most common causes of cognitive decline.

Atrial fibrillation

Atrial fibrillation is the most common cardiac arrhythmia in adults, with the overall prevalence in the US expected to increase from 2.7 million in 2020 to nearly 16 million by 2050. The link between atrial fibrillation and stroke is well known, but the link between atrial fibrillation and cognitive decline requires more research. A large meta-analysis found that atrial fibrillation increases the risk of cognitive impairment by 39%.

Shared risk factors between atrial fibrillation and dementia include high blood pressure, type 2 diabetes, heart failure, smoking, vascular disease, sleep disordered breathing and old age. These factors cause structural and functional brain changes that lead to cognitive decline. Stroke, an important predictor of cognitive impairment, has a direct link to atrial fibrillation. Small brain bleeds, or microbleeds, are also more common in people with atrial fibrillation and are linked to cognitive decline.

Decreased cardiac output associated with atrial fibrillation (similar to heart failure) can compromise blood flow to important parts of the brain responsible for cognitive function. Both atrial fibrillation and Alzheimer’s disease are associated with systemic inflammation, and inflammatory biomarkers are associated with an increased risk of blood clots and brain injury. Although more research is needed to investigate this connection, the observation illustrates the complex interaction between the nervous and cardiovascular systems.

Effective treatment of atrial fibrillation, including the use of anticoagulation medications, rhythm control, or catheter ablation procedures, can reduce the risk of cognitive decline. Ongoing studies are investigating whether restoring normal heart rhythm through catheter ablation can reduce cognitive dysfunction compared to medication alone.

Coronary artery disease

Coronary heart disease significantly increases the risk of dementia and cognitive impairment. A large systematic review of more than 1 million adults indicates that people with heart disease have a 27% higher risk of developing dementia compared to people without heart disease. Up to 50% of people experience loss of brain function after a heart attack. Data from multiple large-scale studies show that heart attack is associated with greater declines in cognitive function, including memory and executive function. Increased levels of calcium buildup in the arteries are also linked to a greater risk of developing dementia.

Coronary heart disease can damage brain function through several mechanisms. Common risk factors such as high blood pressure and type 2 diabetes cause inflammation that compromises the blood-brain barrier and reduces blood flow to the brain, leading to cognitive decline and dementia. Heart disease is also linked to disease of the small blood vessels in the brain and reduced blood flow in the brain, resulting in cognitive impairment. These problems are also seen in patients with Alzheimer’s disease, indicating a close link between blood vessel damage and brain degeneration. In addition, genetic factors that increase the risk of cardiovascular disease may also contribute to brain shrinkage and cognitive decline.

Improving vascular risk factors may preserve cognitive performance, although the specific effects in patients with coronary heart disease have not yet been fully established. Intensive blood pressure treatment has shown promise in reducing mild cognitive impairment, but not dementia. Other research suggests that controlling cardiovascular risk factors with lifestyle interventions such as diet and exercise can help maintain cognitive health.

Testai said: “Although new medications are being developed that have the potential to treat Alzheimer’s disease, the medical community is well aware that prevention is better than cure. More research is needed to confirm and outline how cardiovascular care can improve brain health.” More research is needed to understand the ways in which gender, race and ethnicity can influence the connection between the brain and heart.”

“Healthcare professionals should approach their patients holistically with an approach to improve heart health throughout their lives. Promoting heart health earlier in life with resources that encourage healthy lifestyles is critical, as is monitoring and managing heart health through resources such as the Association’s Life’s. Essential 8 are important to reduce the risk of cognitive impairment.”

This scientific statement was prepared by the volunteer writing group on behalf of the Stroke Council of the American Heart Association; the Cardiopulmonary, Critical Care, Perioperative Care and Resuscitation Council; the Cardiovascular and Stroke Nursing Council; and the Council for Hypertension. Scientific statements from the American Heart Association promote greater awareness of cardiovascular disease and stroke and help facilitate informed healthcare decisions. Scientific explanations indicate what is currently known about a topic and in which areas additional research is needed. Although scientific statements support the development of guidelines, they do not make treatment recommendations. The American Heart Association Guidelines contain the Association’s official clinical practice recommendations.