Photo: Abdülkadir Vardi, Unsplash
Nathan Cross
“Insomnia is a sleep disorder, but it’s primarily a psychological disorder where you’re perceiving that your sleep has a negative impact on you in the daytime,” he says. “And we found that it was only in those with the daytime complaint who had the deficiency in memory performance.”
Cross was also part of a follow-up study published in SLEEP showing that those whose sleep quality worsened between 2019 and 2022 were also more likely to experience memory decline.
Although these studies don’t prove that bad sleep is among the causes of dementia, they do show a direct link between chronic insomnia and memory loss, which can lead to conditions such as Alzheimer’s disease. They also add to a growing body of research that suggests that insomnia is associated with a significant risk of dementia.
Cross, now a research fellow at the University of Sydney, Australia, says that there is a lot more to unpack with the sleep-dementia link. And he believes that new improvements in technology will help make that happen.
“A lot of the blood-based biomarkers are much better at predicting who’s at risk for cognitive decline, and I think the link between those and sleep is going to be really important,” he says. “Even tools like MRI are constantly improving, and I think we’ll soon understand more about the brain-structure changes related to sleep.”