A new analysis identifies long-term hypertension as a possible explanation for why black people are more likely than white people to develop dementia later in life.

"The study results suggest that blacks' higher cumulative blood pressure levels contribute to black-white differences in later-life cognitive decline," say lead author Deborah Levine, M.D., M.P.H., and colleagues.

The Michigan Medicine researchers analyzed pooled cohort data from more than 19,000 participants over a median follow-up of 12 years. They compared participants' blood pressure levels, along with three cognitive measures: global cognition, memory and executive function. Black individuals had faster declines in global cognition and memory than white individuals, differences that were equivalent to 2.5 to 4 years of cognitive aging, researchers say.

When the researchers adjusted for cumulative mean systolic blood pressure levels, though, the racial differences in cognitive decline were no longer statistically significant.

Paper cited: "Association Between Blood Pressure and Later-Life Cognition Among Black and White Individuals." JAMA Neurology. DOI: 10.1001/jamaneurol.2020.0568