Risk for major adverse CV events elevated with type 2 diabetes, cognitive impairment

Adults with type 2 diabetes and cognitive impairment are more likely to experience major adverse cardiovascular events, stroke or CV mortality compared with those without cognitive impairment, according to study findings.

In an analysis of data from the REWIND trial, participants who scored 1.5 standard deviations below their country’s geometric mean on the Montreal Cognitive Assessment and the Digit Symbol Substitution Test were more likely to experience major adverse CV events, making cognitive impairment a potential predictor for CV health outcomes.

“These findings highlight the relevance of cognitive function as an important risk factor for CV outcomes and suggest that patients with cognitive impairment should be offered proven cardioprotective therapies to mitigate their future risk of CV outcomes,” Hertzel C. Gerstein, MD, MSc, professor and population health institute chair in diabetes research and care at McMaster University and Hamilton Health Sciences in Ontario, Canada, told Healio.

Researchers collected data from 8,772 REWIND participants with type 2 diabetes who completed both the Montreal Cognitive Assessment and the Digit Symbol Substitution Test at baseline, 2 years, 5 years and their final trial visit. The Montreal Cognitive Assessment is a 30-item questionnaire assessing seven cognitive domains. The Digit Symbol Substitution Test presents nine symbols above blank squares, with a key corresponding each symbol to a number. Participants must place the correct number in each square in a spvan of 2 minutes. Scores on each test were standardized based on the participant’s country. Adults with a score 1.5 standard deviations below the mean score in their country were defined as having country-standardized substantive cognitive impairment. Those who had a mean score on both tests combined 1.5 standard deviations below their country’s mean were defined as having substantive cognitive impairment based on the geometric mean. Primary outcomes were incident major adverse CV events, incident stroke and CV mortality.

The findings were published in The Journal of Clinical Endocrinology & Metabolism.

Of the study cohort, 10.3% had substantive cognitive impairment and 6% had substantive cognitive impairment based on the geometric mean. Participants with substantive cognitive impairment did not have a significantly increased risk for major adverse CV events after adjusting for albuminuria, estimated glomerular filtration rate and retinopathy. However, in a fully adjusted model, those with substantive cognitive impairment based on the geometric mean had an increased risk for major adverse CV events compared with those without cognitive impairment (adjusted HR = 1.38; 95% CI, 1.09-1.77; P = .009).

Participants with substantive cognitive impairment (aHR = 1.35; 95% CI, 1.11-1.64; P = .002) and substantive cognitive impairment based on the geometric mean (aHR = 1.54; 95% CI, 1.22-1.93; P < .001) had an increased risk for either stroke or CV death compared with adults without cognitive impairment.

“These findings are consistent with other research suggesting that low cognitive scores on cognitive tests were a risk factor for a cardiovascular outcome,” Gerstein said. “This research extended those findings by using a composite measure of cognitive scores and prespecifying a threshold labeled substantive cognitive impairment. It also reported a novel way of combining the cognitive scores by calculating their geometric mean.”

For more information:

Hertzel C. Gerstein, MD, MSc, can be reached at gerstein@mcmaster.ca.