Cardiovascular Health and Cognitive Decline: What Is the Connection?

Cerebrovascular Structure and Function in Young Adults

Wilby Williamson, BMBS, Sports and Exercise Medicine Physician and Clinical Research Fellow in Cardiovascular Medicine at the University of Oxford, United Kingdom, and colleagues conducted a cross-sectional, observational study to examine relationships between modifiable cardiovascular risk factors and cerebrovascular structure, function, and white matter integrity in young adults. The study included 125 adults ages 18 to 40 without clinical evidence of cerebrovascular disease. Participants had a mean age of 25, and 49% were women.

The researchers assessed patients’ cerebral vessel density, caliber, and tortuosity and brain white matter hyperintensity lesion count. In a subgroup of 52 participants, they assessed cerebral blood flow.

The researchers determined for each participant how many of eight modifiable risk factors were at recommended levels (ie, BMI < 25, highest tertile of cardiovascular fitness or physical activity, alcohol consumption < eight drinks per week, nonsmoker for more than six months, blood pressure on awake ambulatory monitoring < 130/80 mm Hg, a nonhypertensive diastolic response to exercise [ie, peak diastolic blood pressure < 90 mm Hg], total cholesterol < 200 mg/dL, and fasting glucose < 100 mg/dL).

On average, participants had six of the eight modifiable cardiovascular risk factors at recommended levels.

In multivariable models, cardiovascular risk factors were associated with cerebrovascular structure and the number of white matter hyperintensities. “For each additional modifiable risk factor categorized as healthy, vessel density was greater by 0.3 vessels/cm³, vessel caliber was greater by 8 μm, and white matter hyperintensity lesions were fewer by 1.6 lesions. Among the 52 participants with available data, cerebral blood flow varied with vessel density and was 2.5 mL/100 g/min higher for each healthier category of a modifiable risk factor,” Dr. Williamson and colleagues said.

The findings suggest that “some individuals may be starting to diverge to different risk trajectories for brain vascular health in early adulthood,” the researchers said. The study was exploratory, however, and follow-up studies are needed to determine the clinical significance of these findings, they said.

“The magnitude of changes was generally much less than would be expected to produce clinical symptoms such as cognitive impairment or gait difficulty,” said Drs. Saver and Cushman. The changes, however, “may portend more substantial abnormalities later in life,” they said. “Even during the late-life period, when septuagenarians become octogenarians, cardiovascular health is associated with substantial differences in cognitive trajectory and dementia onset.”

—Jake Remaly

Suggested Reading

Samieri C, Perier MC, Gaye B, et al. Association of cardiovascular health level in older age with cognitive decline and incident dementia. JAMA. 2018;320(7):657-664.

Saver JL, Cushman M. Striving for ideal cardiovascular and brain health: It is never too early or too late. JAMA. 2018; 320(7):645-647.

Williamson W, Lewandowski AJ, Forkert ND, et al. Association of cardiovascular risk factors with MRI indices of cerebrovascular structure and function and white matter hyperintensities in young adults. JAMA. 2018;320(7):665-673.