When people lose their train of thought, they sometimes refer to it as having a "senior moment."
But those moments are not so senior after all, and they actually have been rising sharply among young adults in recent years, a new study shows.
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The research, published Wednesday in the journal Neurology, cites a profound increase in cognitive disability among adults under 40 as a public health concern. The study defines cognitive disability as having "serious difficulty concentrating, remembering, or making decisions, due to a physical, mental, or emotional condition."
Overall, cognitive disability rose from 5.3% in 2013 to 7.4% in 2023. For adults under 40, rates jumped from 5.1% to 9.7%. In 2023, nearly 1 in 10 adults under 40 reported cognitive disability.
"I was shocked at first," study author Ka-Ho Wong, a research associate of neuroimmunology at University of Utah Health, said in a press release. "The younger population actually nearly doubled in terms of reporting cognitive disability."
Conversely, cognitive disability rates among people 70 and older dipped a bit, falling from 7.3% in 2013 to 6.6% in 2023.
The easy conclusion for the increase in cognitive issues among young people might be ripple effects from the COVID-19 pandemic. But the researchers do not believe this to be the case and even excluded self-reported data from 2020 because of stressors unique to that year.
The researchers hypothesized, instead, that job market insecurity and other economic factors might be partly to blame. Reduced stigma about talking about mental health issues also may account for some of the increased reporting in cognitive disability, the researchers said.
"The 18-to-39-year-old population might think that it is simply OK to talk about this," Wong said. "But does this account for all of this increase? Probably not, but we don't know. That's why we need further study."
A key note about the study: It looked at self-reported cognitive disability using more than 4.5 million responses to an annual phone survey of U.S. adults conducted by the Centers for Disease Control and Prevention. The survey asked people how often they were having trouble concentrating, remembering or making decisions because of physical, mental or emotional conditions.
These self-reports are not clinical diagnoses of mild cognitive impairment or dementia.
But even though self-reported cognitive disability "is not a clinically validated diagnosis, its rising prevalence carries important implications for public health," the researchers wrote.