Recent research has shown that events such as heart attacks or angina pectoris can accelerate the loss of cognitive abilities.
Previous studies investigating the relationship between blood circulation problems and cognitive decline usually focused on events affecting blood flow to the brain. However, few of these studies have investigated the long-term links between coronary heart disease and cognitive decline.
A recent study looked closely at cognitive decline before and after coronary heart disease. The authors explained: "Accelerated cognitive decline occurred after the onset of heart disease, not before it". They claimed that their results highlighted the long-term relationship between heart disease and cognitive decline.
According to Dr. Wuxiang Xie, the lead author of the study, it is important to detect memory loss as early as possible, treat it and delay its progress, as no drug against dementia is available yet. He further explained: "Even the smallest changes in cognitive functions can increase the risk of dementia in the long run".
Dr. Xie's research team believes that the new study is one of the largest cognitive decline studies before and after diagnosed coronary heart disease.
For their analysis, the researchers used the English Longitudinal Study of Aging (ELSA) and evaluated the data of 7,888 participants aged 50 and over. The ELSA project collected data from study participants twice a year from 2002 to 2017. At the beginning of the study, there was no history of coronary heart disease and no diagnosis of dementia or Alzheimer's disease.
Dr. Xie's research team excluded in its evaluations all participants who had not completed all cognitive tasks or who had suffered a stroke during the average observation period of twelve years.
In the follow-up period of the ELSA project, the participants had to complete three cognitive function tests performed by the researchers in 8 waves. The tests dealt with verbal memory, semantic memory and sense of time.
During the study phase, 5.6% of the participants had angina pectoris or even a heart attack. The tests showed a faster loss of cognitive abilities in each of the affected persons than in participants without coronary heart disease.
Respondents who developed angina had a faster loss of sense of time, while participants with heart attacks had a faster loss of verbal memory and semantic memory.
The authors of the current study explained: "We discovered that after the onset of coronary heart disease, there was a high degree of association with faster loss of cognitive function. This was not the case with cognitive changes in the years before the event and with short-term changes afterward."
On the occasion of the discoveries, the researchers suspect that reduced oxygen supply to the brain is the most likely reason for the link between coronary heart disease and accelerated cognitive decline. Therefore: "Patients who have suffered a heart attack or angina pectoris should be under special observation in the years following diagnosis," said Dr. Xie.
Xie W et al., Cognitive Decline Before and After Incident Coronary Events. Journal of the American College of Cardiology. 2019; 73(25): 3041-3050