The symbiosis of mind and heart

People aged 75 and over account for about one-third of heart attack patients, and more than half of them die in the hospital as a result of the infarction. So far it was not known whether the mental condition influences the prognosis of older heart attack patients.

Cognitive impairment directly affects mortality from heart disease

People aged 75 and over account for about one-third of heart attack patients, and more than half of them die in the hospital as a result of the infarction. So far it was not known whether the mental condition influences the prognosis of older heart attack patients.

The risks of dementia, Alzheimer's, confusion and delirium increase with age. Older people also have a much higher risk of suffering a heart attack. People aged 75 and over account for about one-third of heart attack patients, and more than half of them die in the hospital as a result of the infarction. So far it was not known whether the mental condition influences the prognosis of older heart attack patients. At the ESC 2018 in Munich, three current studies were presented which prove that the mental condition of older patients with coronary diseases is apparently more important for the clinical picture than previously assumed. The results lead to the recommendation to fundamentally test cognitive perception at a certain age in order to be able to carry out effective treatment management. 

Unknown brain damage in patients with atrial fibrillation

The Swiss Atrial Fibrillation Cohort Study (Swiss-AF) examined patients with atrial fibrillation for previously unknown brain damage and found that four out of ten patients were affected. Patients with atrial fibrillation have a significantly increased risk of stroke, which is why most are treated with blood thinners (oral anticoagulation). The increased risk of stroke is probably the main reason why patients also have an increased risk of cognitive dysfunction and dementia. However, the relationship between atrial fibrillation and dementia has also been shown in patients without prior stroke, which means that additional mechanisms must be involved. The aim of the prospective observational study was to demonstrate these mechanisms of cognitive decline in patients with atrial fibrillation and to measure the frequency of silent brain damage.

Between 2014 and 2017, 2,415 patients over 65 years of age with atrial fibrillation were enrolled in the study from 14 centers in Switzerland. All patients without contraindications received standardized magnetic resonance imaging of the brain. The images were then analyzed in a central core laboratory. The final analysis included 1,389 patients with atrial fibrillation without a history of stroke or transient ischemic attacks. 

It was found that four out of ten patients with atrial fibrillation had clinically undetected brain lesions that could be responsible for cognitive decline. These data will now be further analyzed to see whether patients with silent brain lesions also have impaired cognitive function. "Our results suggest that clinically undetected brain damage can explain the link between dementia and atrial fibrillation in stroke-free patients," said Co-Principal Investigator Professor David Conen of McMaster University, Hamilton, Canada.

Testing the mental condition of patients after their first heart attack

In this study by Beygui et al (2018) from France, the influence of mental condition on mortality risk was investigated in 600 patients aged >75 years after acute coronary syndrome (ACS).  The mental state was assessed with the Mini-Mental-State-Investigation (MMSE) and the Confusion-Assessment-Method (CAM). Both tests are routinely used for screening and assessing the severity of dementia or confusion in clinical and research settings.

The analysis revealed cognitive impairment in 174 (29%) patients. One year after their heart attack, patients with impaired mental function were more than twice as often dead as patients with a healthy mental condition. The mental confusion was also associated with an almost four-fold higher rate of bleeding complications in the hospital and a more than a two-fold higher risk of being hospitalized again with cardiovascular problems within three months of discharge.

The assessment of the mental condition at the bedside after admission allows further identification of high-risk patients in an already high-risk population and can be routinely considered by physicians in such patients. According to study author Professor Farzin Beygui of the Caen University Hospital, further studies are needed to assess whether cognitive impairment detection and subsequent specific management could lead to improved outcomes in older ACS patients. 

Routine tests for high blood pressure patients: clock drawing

The Heart-Brain study in Argentina evaluated the usefulness of the clock drawing test (hereafter clock test) compared to the mini-mental state examination (MMSE) test to detect cognitive impairment in 1,414 adults with average high blood pressure recruited from 18 cardiology centers in Argentina. The average blood pressure was 144/84 mmHg, the average age was 60 years and 62% of the subjects were women.

For the clock test, participants were asked to write the numbers of the clock in the correct position within the circle and then drag the hands to the clock indicating the time "twenty to four". The patients were classified as normal, moderate or severely cognitively impaired. The MMSE has 11 questions and generates a score of 30 that indicates no (24-30), mild (18-23), or severe (0-17) cognitive impairment. The researchers found a higher prevalence of cognitive impairment with the clock sign test (36%) compared to the MMSE test (21%). Three out of ten patients with a normal MMSE score had an abnormal clock test result. The differences in the results suggest that the clock test should be preferred to MMSE for the early detection of executive dysfunction in patients with hypertension.

"The ability to draw the numbers of a clock and a certain time is an easy way to find out if a patient with high blood pressure has a cognitive impairment," said study author Dr. Augusto Vicario of the Heart and Brain Department of the Cardiovascular Institute in Buenos Aires, Argentina. The development of dementia can thus be counteracted at an early stage. The results show that more than one-third of patients were at risk of developing dementia. The clock drawing test should be used as a routine screening tool for cognitive decline in patients with hypertension. Further studies are needed to determine whether lowering blood pressure can prevent progression to dementia in the long term.

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