# Karolinska: healthy sleep tied to larger brain volume in 54,017 people with cardiometabolic disease

- Published: 2026-11-05 09:47 UTC
- Section: Life & Health › Neurotechnology
- Tags: healthy sleep and brain health, cardiometabolic disease and cognition, type 2 diabetes and dementia risk, UK Biobank sleep study, brain MRI gray matter volume, sleep score insomnia snoring, Karolinska Institutet study
- URL: https://realtech.media/news/rt-bd6f1a7f5e0335d645116478_karolinska_healthy_sleep/

**An observational UK Biobank analysis found that adults with diabetes, heart disease or stroke and healthy sleep had higher cognitive scores and larger brain volumes than poor sleepers.**

![Karolinska: healthy sleep tied to larger brain volume in 54,017 people with cardiometabolic disease](https://sgzwpqqelzmajkcubgkl.supabase.co/storage/v1/object/public/rt-media/2026/11/0c61e3a1322aad0c.jpg)
*Bobjgalindo, Wikimedia Commons, CC BY-SA 4.0*

Researchers at Karolinska Institutet analysed data from 408,977 adults in the UK Biobank. They report in the Journal of the American Heart Association, published on 4 November 2026, that people with cardiometabolic diseases (CMDs) and a healthy sleep pattern had higher cognitive scores and larger brain volumes than people with CMDs and poor sleep [1]. At baseline, 54,017 participants (13.2%) had at least one CMD, a group that includes type 2 diabetes, heart disease and stroke [1].

## Study design and sleep score

CMDs were identified from medical records, medication use and medical history. Sleep was assessed with a composite score based on five factors: sleep duration, chronotype, insomnia symptoms, snoring and daytime sleepiness. Participants were classed as having a healthy, intermediate or poor sleep pattern [1].

A subsample of 34,913 people underwent brain magnetic resonance imaging. The measures included volumes of total brain, gray matter, white matter and hippocampus, as well as white matter hyperintensities. The authors used linear regression models to examine the joint status of CMD (yes or no) and sleep against global and domain-specific cognitive scores and the imaging measures [1]. The study is observational.

## Cognitive and MRI results

Among people with CMDs, those with healthy sleep scored higher than those with poor sleep on global cognition (β=0.02, 95% CI 0.01–0.05), verbal and numeric reasoning (β=0.07, 95% CI 0.01–0.12) and processing speed (β=0.07, 95% CI 0.04–0.10) [1].

The imaging analysis showed the same direction. In people with CMDs, healthy sleep versus poor sleep was associated with larger total brain volume (β=0.22, 95% CI 0.08–0.35), gray matter volume (β=0.23, 95% CI 0.09–0.36) and white matter volume (β=0.19, 95% CI 0.05–0.33) [1]. According to the Karolinska Institutet release, the link between sleep and brain structure was more pronounced in people with these conditions than in those without them.

The authors conclude that healthy sleep may attenuate the associations of CMDs with poorer cognitive performance and markers of brain atrophy, and describe sleep as a modifiable factor [1]. Abigail Dove of the Aging Research Center at Karolinska Institutet said the findings suggest that healthy sleep may help offset some of the adverse consequences of cardiometabolic disease for the brain. Because the design is observational, the results show an association and do not establish cause.

## Sources

1. [Journal of the American Heart Association](https://doi.org/10.1161/JAHA.126.051940)
2. [EurekAlert](https://www.eurekalert.org/news-releases/1150136)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-bd6f1a7f5e0335d645116478_karolinska_healthy_sleep/