Heart failure has been linked to detrimental changes in the brain, says new research published recently in the European Heart Journal. The condition may occur due to ischemic heart disease or high blood pressure, and affects about three percent of all adults.
As heart failure has been linked to depression and cognitive impairment, Professor Osvaldo Almeida of the University of Western Australia, and colleagues investigated whether this is specifically due to the heart failure itself, or one of its causal factors.
They analysed data on 35 heart failure patients, 56 ischemic heart disease patients without heart failure, and 64 healthy people with neither condition. All were aged 45 years or above and had no obvious cognitive impairment. Magnetic resonance imaging (MRI) scans of the participants’ brains were assessed.
This is the first study of cognitive changes in heart failure to include patients with ischemic heart disease.
Participants with heart failure had a lower volume of grey matter in many areas of the brain than the other two groups. These patients also had lower scores on short- and long-term memory, had longer reaction speeds, and took longer to complete a reasoning task.
Professor Almeida explains, “What we found in this study is that both ischemic heart disease and heart failure are associated with a loss of cells in certain brain regions that are important for the modulation of emotions and mental activity. Such a loss is more pronounced in people with heart failure. Health professionals and patients need to be aware that problems caused by heart disease are not limited to the heart.”
In their paper, the researchers conclude, “Adults with heart failure have worse immediate and long-term memory and psychomotor speed than controls without ischemic heart disease.”
This could make it more difficult for patients to comply with complicated treatment regimes, they warn, stating, “Our findings are consistent with the possibility that patients with heart failure may have trouble following complex management strategies, and, therefore, treatment messages should be simple and clear.”
They add that further studies will have to be done to uncover the process by which heart failure leads to loss of brain cells, to see whether the problems become worse over time, and to discover whether patients could benefit from cognitive rehabilitation.
Natasha Stewart of the British Heart Foundation commented: “Heart failure can affect people in very different ways. More research is needed to confirm the effect on mental processes, so that treatment can be targeted to look after patients in the best possible way.
“The biggest implication of this research is that patients may find it difficult to stick to treatment regimes and forget to take their medication. It is important to speak to your doctor about what is best for you. Together you can find a way to make your meds a part of your daily routine so that they are less easily forgotten.”
Responding to the study, Dr. Christiane Angermann and colleagues at the University of Wurzburg, Germany, say that links between cardiovascular disease and dementia have been observed for decades. In fact, the label “cardiogenic dementia” was first used in 1977.
Smaller studies on humans have investigated the issue, with inconsistent results. A few animal studies have also been carried out, and these studies showed changes to the brain after a heart attack.
Another potential cognitive problem among heart failure patients is an inability to decide what to do if their condition changes. For example, a patient who has a cognitive problem and experiences sudden weight gain may not think to notify their physician. Their condition could worsen over time, resulting in an avoidable trip to the emergency room.
Richard S. Isaacson, MD, a neurologist at the University of Miami School of Medicine, recommends that patients bring a family member or caregiver to doctor appointments to help understand the treatment regime and the importance of taking medication consistently.
“People with heart failure are going to have trouble understanding because their thinking skills are not as strong as they used to be,” Isaacson says. “They often have multiple medical problems and difficulty understanding what they can do to help themselves.”
He supports the use of handouts to explain heart failure and its treatments, to help remind patients of what they need to do and why.
Cognitive and brain changes associated with ischaemic heart disease and heart failure. Almeida, O. P. et al. The European Heart Journal, February 1, 2012. doi:10.1093/eurheartj/ehr467
Cognition matters in cardiovascular disease and heart failure. Angermann, C. E., Frey, A.. and Ertl, G. The European Heart Journal May 29, 2012 doi:10.1093/eurheartj/ehs128