A higher sleep-derived Brain Health Score in midlife predicted better cognitive performance more than a decade later, according to study results published in Sleep.Researchers evaluated whether a sleep-derived Brain Health Score measured using electroencephalogram (EEG) data in midlife was associated with later cognitive performance among participants in the Framingham Heart Study. The analysis included participants (N=426) enrolled in the Sleep Heart Health Study who underwent at least 1 in-home polysomnography assessment and subsequent neuropsychological testing.

Among the participants, the mean (SD) age was 55.9 (8.2) years at polysomnography and 70.4 (8.1) years at cognitive testing; 55% were women, 86% were non-Hispanic White, the mean (SD) BMI was 27.7 (5.0) kg/m2, and 41% had a college education.

 

These findings add to the growing body of evidence linking sleep EEG features with cognitive function…

Each 1-SD higher Brain Health Score was associated with higher digital clock drawing test (b, 0.16; 95% CI, 0.06-0.26), memory (b, 0.14; 95% CI, 0.04-0.24), language (b, 0.13; 95% CI, 0.03-0.23), and executive function (b, 0.11; 95% CI, 0.02-0.20) scores at an average follow-up of 12.6 years.

These associations remained significant when the 8 participants diagnosed with dementia during follow-up were excluded. Similarly, findings remained robust after additional adjustment for potential mediators (adjusted b range, 0.09-0.15).

When 2 sleep assessments were evaluated separately, Brain Health Score calculated using the earliest assessment remained associated with digital clock drawing test (b, 0.15; 95% CI, 0.05-0.25), memory (b, 0.11; 95% CI, 0.01-0.21), language (b, 0.11; 95% CI, 0.01-0.21), and executive function (b, 0.10; 95% CI, 0.01-0.19) scores at a follow-up of 16.6 years. Associations using the latest assessment at an average follow-up of 11.7 years were smaller (b range, 0.06-0.12). However, when both Brain Health Scores were included in the same model, no associations remained significant.

Study limitations include the predominantly White study population, inability to account for baseline digital clock drawing test performance, potential residual confounding, and reliance on a single night of polysomnography data.The researchers concluded, “This study found that participants with a higher sleep-derived Brain Health Score in mid-to-late life had better digital clock drawing test performance, memory, executive function, and language scores on average 12.6 years later. These findings add to the growing body of evidence linking sleep EEG features with cognitive function and extend this work to suggest that integrated sleep EEG scores are also associated with future performance on both digital and traditional [neuropsychological] tests.”

Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.