Older adults whose sleep duration varied over the course of a two-decade-long study were much more likely to develop cognitive decline compared with those whose sleep duration did not vary significantly, new research shows.
“Our finding tells us that maintaining healthy, consistent sleep habits long-term may be important in optimizing brain health as you age. So making sure that good sleep is a regular part of your life —not just on weekends, and not just on vacations — is important,” said Dr. Jeffrey Iliff, a professor of psychiatry and behavioral sciences and neurology at the University of Washington School of Medicine.
Iliff, who also conducts research at the VA Puget Sound Health Care System, led the investigation. Samantha Keil, formerly of UW and now a senior research fellow at Weill Cornell Medicine, was the paper’s lead author. They and colleagues report their findings today in the journal JAMA Network Open.
Previous research has suggested that sleep of short duration, less than six hours a night, increases the risk of cognitive decline. The new study also found this to be true. But the finding that variation of sleep duration appeared to affect cognitive decline is new.
I call cap on the study. Correlation is not causation and it could simply be that the things that caused mental decline, are also the reason for the poor sleep patterns.
My chronic anxiety ruins my sleep despite always giving myself over 8 hours of time to sleep.
My having to pee ruins mine. Then once I’m up the overthinking keeps me up. I try to have a catalog of unimportant shit to obsess over to make me fall back asleep.
Correlation is not causation
That’s addressed in the article:
It is unknown why short, or disturbed, sleep and cognitive decline appear linked, and the connections between these two processes are complex.
This is a more nuanced statement than “correlation is not causation” yet means pretty much the same thing. In medicine, the sciences, sociology, and personal anecdotal evidence, correlation and patterns are where research starts. Honest researchers understand the use and misuse of statistics (for both science and profit). Generally (with plenty of exceptions) once correlations are found the search for mechanisms can begin. So one could say “correlation can lead to causation,” and not be far wrong.
Did the study explicitly claim causation?
Yes, it’s in the summary above:
“Our finding tells us that maintaining healthy, consistent sleep habits long-term may be important in optimizing brain health as you age.”
Implying that poor sleep is directly causative instead of some underlying pathology being causative of both poor sleep and cognitive decline.
It says may be important, which is supported by the study. It may be, and this is good evidence to have when arguing for resources and funding for future research with more predictive power.
It doesn’t imply causality; that’s what you read. It presents the possibility of it, which is valid and completely normal in research.
If this does turn out to be true I’m so fucked
Chronic insomnia FTW. I for one absolutely love having things I’ve known and experienced first-hand for decades confirmed. I love this dystopia I live in!
Same, I’m not cut out for a world that wakes with the sun.
Was thinking the same for myself.
This isn’t surprising
