July 2023
History of myocardial infarction may accelerate age-related cognitive decline
By Rebecca Jenkins
Incident myocardial infarction (MI) is associated with an accelerated long-term decline in cognition, memory and brain function, research finds, but not an acute decline at the time of the event.
The cohort study, published in JAMA Neurology, included 30,465 adults without a history of MI, stroke, or dementia at baseline, 1033 of whom went on to have one or more MI events during follow up (median 6.4 years).
The researchers found that incident MI was not associated with a sudden decrease in global cognition, memory, or executive function at the time of the event compared with no MI. However, there was a significantly faster rate of cognitive decline over time for adults who had an MI compared with those who did not.
Incident MI was associated with a −0.15 points per year decline in global cognition scores, a −0.13 points per year decline in memory scores and a −0.14 points per year in executive function scores.
‘The decline in global cognition after incident MI was equivalent to six to 13 years of cognitive aging, representing an important public health problem,’ the researchers wrote.
The research used data pooled from six large population-based US cohort studies, with the total cohort having a median age of 64 years and with women representing more than half the population.
The association was independent of clinical stroke and atrial fibrillation and not explained by a second MI event, the researchers added.
Race affected the association, with Black people more likely than White people to have an acute decline in global cognition at the time of the event but less likely to have a decline over the years after an MI.
The researchers also found a sex-specific effect, with women having less of a decline in global cognition than men but more of a decline in executive function.
Professor Craig Anderson, Director of Global Brain Health at The George Institute for Global Health in Sydney and Professor of Neurology and Epidemiology at the Faculty of Medicine, UNSW Sydney, said this paper provided a fresh perspective on the known link between cardiovascular risk factors and cognitive impairment and dementia.
Due to its large size and long follow-up period, the study had also addressed limitations of previous epidemiological studies and accounted for various confounding factors, such as early post-MI mood disturbance.
‘These data suggest having a heart attack triggers some systematic “stress” in the body, such as inflammation, that enhances pathological processes that affect brain health,’ he told Medicine Today.
Professor Anderson said the results were not strong enough to suggest that clinicians should increase their detection of cognitive impairment in their patients who have had a heart attack.
‘But they do re-enforce the importance of efforts aimed at lifestyle modification as part of cardiac rehabilitation and secondary prevention to improve quality of life and longevity in this high-risk patient group,’ he said.