Study Finds Sleep Troubles Associated with Cognitive Impairment in Later Life

A study from the American Academy of Sleep Medicine indicates that trouble falling asleep was the primary symptom of insomnia that predicted cognitive impairment 14 years later, according to the press release.

The study authors examined data from the Health and Retirement Study, which included 2496 individuals who were at least 51 years of age. In 2002, the participants reported the frequency of insomnia symptoms, whereas in 2016, the participants' cognition was evaluated as part of the Harmonized Cognitive Assessment Protocol. The study was further operationalized with a comprehensive neuropsychological battery evaluating episodic memory, executive function, language, visuoconstruction, and processing speed, according to the study authors.

"While there is growing evidence for a link between insomnia and cognitive impairment in older adults, it has been difficult to interpret the nature of these associations given how differently both insomnia and cognitive impairment can present across individuals," said lead author Afsara Zaheed, a graduate student in clinical science within the department of psychology at the University of Michigan, in the press release. "By investigating associations between specific insomnia complaints and cognition over time using strong measures of cognitive ability, we hoped to gain additional clarity on whether and how these different sleep problems may lead to poor cognitive outcomes."

The findings showed that the symptom of having trouble falling asleep that was recorded in 2002 was linked to cognitive impairment in 2016. The study results showed a link between frequent bouts of having trouble falling asleep with worse episodic memory, executive function, language, processing speed, and visuospatial performance in later years. The results also showed that links between sleep patterns and cognition later on were partially explained by both depressive symptoms and vascular diseases in 2014 for all domains except episodic memory, which was only partially explained by depressive symptoms, according to the study authors.

"These results are important given the lack of currently available treatments for late-life cognitive disorders, like Alzheimer's disease and other dementias," Zaheed said in the press release. "Sleep health and sleep behaviors are often modifiable. These results suggest that regular screening for insomnia symptoms may help with tracking and identifying people with trouble falling asleep in mid-to-late life who might be at risk for developing cognitive impairments later in life. Additional intervention research is needed to determine whether intervening on insomnia symptoms can help prevent or slow the progression of cognitive impairments in later life."

REFERENCE

Having trouble falling asleep predicts cognitive impairment in later life. EurekAlert! Published June 9, 2021. Accessed June 11, 2021. https://www.eurekalert.org/pub_releases/2021-06/aaos-htf060921.php