Heart attack tied to decline in cognitive function later in life

Myocardial infarction (MI) was associated with a rapid decline in cognitive function, such as global cognition, executive function, and memory, years after the event, according to a study presented at ISC 2022.

“It’s important to know that cognitive decline is a possibility after a heart attack, so physicians are both managing patients’ heart disease and looking for signs of dementia following a heart attack … For too long, we have thought about and addressed heart disease and brain disease as two separate conditions, and based on our study’s findings and other research, I don’t think we’re going to be able to keep doing that as we learn more,” said lead author Dr Michelle Johansen from the Johns Hopkins University School of Medicine in Baltimore, Maryland, US.

“[W]e believe that there is some degree of cognitive ageing that is to be anticipated [even] in patients who do not have an MI. However, we wanted to investigate … the impact of an acute MI on cognition soon after the event and in the long term,” Johansen noted.

The researchers conducted a pooled analysis of six longitudinal cohort studies* involving 31,377 participants (median age 60 years, 56.0 percent female) who had no history of MI and dementia based on the first cognitive assessment. Global cognition, executive function, and memory scores were used to measure cognitive performance, in which higher scores indicate better performance. [ISC 2022, abstract P68]

At a median follow-up of 6.4 years, 1,047 participants had at least one MI event, while 30,330 participants remained free of MI.

Participants with MI showed a significant decline in global cognition and executive function during follow-up after their first MI event compared with those who did not experience an MI (-0.15 and -0.14 points/year, respectively; p<0.0001 for both).

With regard to participants with available data on memory outcome, those with MI also demonstrated a decline in memory in the years following their first MI event compared with those who did not have MI (-0.13 points per year; p=0.005).

Of note, the researchers found no significant association between the effect of MI soon after the event and the decline across all cognitive outcomes (p=0.33 for both global cognition and executive function; and p=0.08 for memory).

Results showed that participants who had a second MI event demonstrated a yearly significant change in cognitive function after the initial MI (-0.13 points; p<0.0001), which was anticipated, Johansen noted.

However, there was no statistical difference between pre- and post-decline in cognition among those who had a second MI event (-0.15 points/year; p=0.15), suggesting that “the accelerated cognitive decline associated with the initial MI is not explained by recurrent MI events,” said Johansen.

“Incident MI was associated with a faster decline in global cognition, memory, and executive function over the years following the MI event compared with those who did not have an MI, even after adjustment for important potential confounders,” Johansen concluded.

“We need to realize that what’s going on in the heart and brain are related. Managing risk factors to prevent a heart attack is actually good for your brain as well … [Therefore,] I would suggest that future research should consider subclinical infarct, hypoperfusion, inflammation, and shared risk factors in the investigatory model,” she added.

*Atherosclerosis Risk in Communities Study (ARIC), Multi-Ethnic Study of Atherosclerosis (MESA), Coronary Artery Risk Development in Young Adults Study (CARDIA), Cardiovascular Health Study (CHS), Framingham Offspring Study (FOS), and Northern Manhattan Study (NOMAS)