“Cardiovascular diseases such as heart disease and stroke have been associated with an increased risk for cognitive impairment and dementia in older adults, but less is known about how having these diseases before age 60 impacts cognition and brain health over the course of life,” said study author Xiaqing Jiang, PhD, of the University of California, San Francisco. “Our study found that cardiovascular events earlier in life are associated with worse cognition, accelerated cognitive decline and poor brain health in middle age.” 3,146 participants were examined for the study.
Participants in the study, who ranged in age from 18 to 30 at the start, were followed for up to 30 years. At the end of the trial, they were on average 55 years old. Early cardiovascular disease was defined as having coronary heart disease, stroke, congestive heart failure, carotid artery disease, or peripheral arterial disease before the age of 60, and it afflicted 147 people, or 5% of the population. A first cardiovascular event was common at the age of 48.
Participants were given five cognitive tests after being observed for three decades. Global cognition, processing speed, executive function, delayed verbal memory, and verbal fluency were all tested in the assessments. On five out of five tests, people with early cardiovascular disease fared worse than those who did not. In a 10-minute recall test with scores ranging from zero to 15, people with early cardiovascular disease outperformed those without, with an average score of 6.4 vs an average score of 8.5.
In a global cognitive exam with a score range of zero to 30, those with early cardiovascular disease had an average score of 21.4, whereas those without cardiovascular disease had an average score of 23.9. A score of 26 or more is regarded usual, whereas a score of 22 is considered ordinary for those with mild cognitive impairment.
Six hundred participants got brain scans to assess white matter hyperintensities and white matter integrity. White matter hyperintensities are commonly associated with vascular damage to the brain’s white matter. Researchers discovered that early cardiovascular disease was associated with more white matter hyperintensities in the brain as well as higher white matter mean diffusivity, indicating a decrease in brain tissue integrity after controlling for cardiovascular risk factors such as diabetes and high blood pressure.
Researchers discovered that early cardiovascular disease was associated with a three times greater likelihood of accelerated cognitive decline over five years in participants who had two sets of cognitive tests 25 and 30 years into the study, with 13% of people with early cardiovascular disease experiencing accelerated cognitive decline compared to 5% of people who did not have the disease.
“Our research suggests that a person’s 20s and 30s are a crucial time to begin protecting brain health through cardiovascular disease prevention and intervention,” Jiang said. “Preventing these diseases may delay the onset of cognitive decline and promote a healthier brain throughout life.”