Heart conditions such as heart failure and atrial fibrillation may not only be tied to stroke but also to cognitive decline and brain injury, according to a recent Scientific Statement from The American Heart Association.
In the statement, published in Stroke, investigators addressed the relationship between cardiovascular disease and brain health. Conditions such as heart failure (HF), atrial fibrillation (AF), and coronary heart disease (CHD) have been associated with cognitive decline and brain injury, including structural changes and impaired cognitive function. The statement discussed the interdependence between heart and brain health, primarily through shared risk factors such as hypertension, diabetes, and obesity.
Mechanistically, cardiovascular disease may lead to reduced cerebral perfusion, chronic inflammation, and microvascular damage, all contributing to cognitive impairment. HF with reduced ejection fraction (HFrEF) has been linked to brain injury and cognitive decline, likely caused by diminished cerebral blood flow and neuroinflammation. Although cognitive dysfunction appears to be more frequent in HFrEF, it may also be present in those with HF with preserved ejection fraction (HFpEF). In 2014, HF had a prevalence of 27 per 1,000 individuals, with an estimated lifetime risk of about 25%. A broad systematic review reported that 43% of participants in HF cohorts experienced cognitive impairment.
AF, the most common sustained arrhythmia, is associated with an increased risk of stroke and cognitive decline. Even in the absence of overt clinical symptoms, AF may be linked to cerebral microhemorrhages and reduced cardiac output, both of which may contribute to brain injury and cognitive dysfunction. A comprehensive meta-analysis found that AF was linked to a 39% higher risk of cognitive impairment in the general population.
CHD is also a contributor to cognitive impairment, primarily through its effects on cerebral microcirculation. The statement detailed that atherosclerosis, vascular inflammation, and disruption of the blood-brain barrier could be associated with conditions such as vascular dementia and Alzheimer's disease. Irregular blood flow altered blood components, and abnormalities in the heart and blood vessel walls can increase the likelihood of thromboembolic stroke, occurring at a rate of up to 2.23 events per 100 person-years in patients with HF, compared with 1.17 events per 100 person-years in those without HF (P < .01).
Full disclosures can be found in the published statement.