Vascular risk-factor burden is associated with a substantially increased risk
for poor memory performance in individuals with coronary artery disease (CAD).

New research presented here at the American Association of Geriatric Psychiatry
2009 Annual Meeting showed that individuals with 5 vascular risk factors had
almost a 7-fold increased risk of having borderline or impaired verbal memory
measured by the California Verbal Learning Test, 2nd ed (CVLT–II).

"There was a very strong relationship between the number of cardiovascular risk
factors in these individuals and their degree of cognitive impairment," lead
investigator Krista Lanctôt, PhD, from Sunnybrook Health Sciences Centre, in
Toronto, Ontario, told Medscape Psychiatry.

Marker of Hippocampal Volume

According to Dr. Lanctôt, a high proportion of CAD patients experience cognitive
impairment, including verbal learning deficits. In addition, observational
studies have shown a link between cognitive impairment and cardiovascular risk
factors including hypertension, diabetes, and dyslipidemia.

However, while CAD may increase the risk of developing mild cognitive impairment
(MCI) or Alzheimer's disease (AD), the nature of this link is unclear, said Dr.
Lanctôt.

To determine whether the cumulative burden of vascular risk factors is
predictive of verbal memory deficits, researchers conducted a cross-sectional
study of 100 patients with a diagnosis of CAD who were undergoing cardiac
rehabilitation at a single center.

The average age of the study cohort was 64 years, and 78% of participants were
men. Subjects had a 50% or greater blockage of at least 1 coronary artery or a
history of prior myocardial infarction or revascularization.

Participants underwent an evaluation of vascular risk factors, including
hypertension, dyslipidemia, diabetes, and obesity, as well as exercise stress
testing and verbal memory assessment.

The researchers chose to measure verbal memory because it is widely considered
to be a marker of hippocampal volume. Dr. Lanctôt pointed out that a recent
study in a cohort of individuals with dementia with Braak stage 4 scores (a
measure of pathological burden of plaques and tangles) showed that the main
difference between subjects with and without cognitive impairment was
hippocampal volume.

Intervention Opportunity?

The results of the current study revealed that each vascular risk factor was
roughly equivalent to remembering 1 word fewer and that at a level of 5 vascular
risk factors individuals had a much greater risk of having a borderline or
impaired CVLT-II score compared with their counterparts with 2 or fewer vascular
risk factors.

"We were surprised at how tight the correlation was between the number of risk
factors and the risk of memory impairment. The good news is that many of these
factors are modifiable, and this may offer us an opportunity to intervene at an
earlier stage with a view to reducing the risk of MCI and possibly Alzheimer's
disease," said Dr. Lanctôt.

Based on these findings, she added, the team is planning a large, multicenter
interventional study of about 400 patients that will examine the impact of
reducing vascular risk factors on subsequent memory loss.

The study was funded by the Drummond Foundation and the Physician's Services
Incorporated Foundation.

American Association for Geriatric Psychiatry 2009 Annual Meeting: Abstract NR
32. Presented March 6, 2009.