FRIDAY, April 24, 2026 (HealthDay News) -- Optimal sleep duration is associated with better executive function, with a significantly higher impact of optimal sleep among those with focal epilepsy, according to a study published online April 22 in Neurology.
Xin You Tai, D.Phil., from the University of Oxford in the United Kingdom, and colleagues conducted an analysis of the prospective U.K. Biobank cohort study to examine the relationship between sleep and cognition and dementia risk in patients with focal epilepsy compared to healthy controls and patients with stroke. The sample included 482,207 participants, aged 38 to 72 years, without dementia at baseline and a nested imaging subsample of 42,345 participants.
The researchers found that in the control, focal epilepsy, and stroke groups, optimal sleep duration (six to eight hours) was associated with better executive function. Compared with controls, individuals with focal epilepsy, but not those with stroke, had a significantly higher impact from optimal sleep. There was an association seen for nonoptimal sleep with worse executive function up to eight years before diagnosis of focal epilepsy. Compared with healthy controls with optimal sleep, individuals with focal epilepsy and nonoptimal sleep had an increased risk for developing dementia (hazard ratio, 5.15); the risk was lower for individuals with stroke with poor sleep (hazard ratio, 3.48). Optimal versus nonoptimal sleep modified the dementia risk in individuals with focal epilepsy, with a significantly greater improvement versus healthy controls, while the stroke group exhibited no significant difference.
"Our study suggests getting optimal sleep may be especially beneficial to cognition and dementia risk in people with focal epilepsy," Tai said in a statement.
Several authors disclosed ties to the pharmaceutical industry.