Some people report a decline in their memory that isn’t significant enough to be measured by standard tests. Known as subjective cognitive decline, this condition is defined by the Centers for Disease Control and Prevention as “the self-reported experience of worsening or more frequent confusion or memory loss” and is associated with increased odds of developing dementia later in life. A new study now shows that the risk may be greater for Black and Latino people.
“Previous studies showing that subjective cognitive decline increased the risk for developing dementia were done with mainly white participants, and the studies that did include Black and Latino people had conflicting results and generally did not follow people over time,” said the new study’s author, Silvia Chapman, PhD, of Columbia University Medical Center in New York City, in an American Academy of Neurology news release. “Our results highlight the importance of carefully evaluating any memory concerns for all of these groups and underscore the potential benefit of screening older adults for subjective cognitive decline.”
Published in the American Academy of Neurology, the study involved 4,043 people with an average age of 75. At the start of the study, participants had neither dementia nor mild cognitive impairment but reported some degree of subjective cognitive decline. The participants included 1,713 Latino people, 1,267 Black people and 1,063 white people.
These groups were asked to rate their subjective cognitive decline according to the number of problems from a list of 10 that they reported experiencing. These included difficulty remembering things they had just read or heard, inability to remember a short list of items, and stopping mid-sentence due to difficulty remembering the right word for something.
After following participants for an average of five years, researchers found that those who reported higher levels of subjective cognitive decline at the start of the study were more likely to develop dementia during the subsequent years. What’s more, every additional point on the 10-point scale was linked with an 8.5% higher risk of developing dementia, which is “roughly comparable to the effect of two years of aging,” according to Chapman.
Compared to people of their race with lower scores, Latinos and Black people with higher subjective cognitive decline scores were, respectively, 8% and 10% more likely to develop dementia.
“These results show that subjective cognitive decline may serve as an early marker of dementia and support the idea that subjective cognitive decline contributes information beyond standard memory testing,” Chapman said.