According to a study published in Neurology, some people report a decline in their memory before the decline is large enough to appear on standardized tests. This subjective cognitive decline is associated with an increased risk of developing dementia in Black and Latinx people.

In the study, subjective cognitive decline was rated according to the number of problems people reported from a list of ten items, including difficulty remembering things they just read or heard; inability to remember a short list of items; and stopping in the middle of saying something because they can’t remember the right word.

The study involved 4,043 participants, average age of 75 years, who did not have dementia or mild cognitive impairment but did report some level of subjective cognitive decline at the start of the study. A total of 1,713 were Latinx, 1,267 were Black, and 1,063 were White.

The participants were followed for an average of 5 years and given tests of their cognitive skills to find out who developed dementia. 

The research found that people with more problems with subjective cognitive decline at the beginning of the study were more likely to develop dementia during the course of the study. 

Latinx people with higher scores for subjective cognitive decline were 8% more likely to develop dementia than Latinx people with lower scores. Black people with higher scores were 10% more likely to develop dementia than Black people with lower scores.

“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,” said Silvia Chapman, PhD, Columbia University Medical Center. “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. 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.”