Thomas RJ, Kim H, Maillard P, DeCarli CS, Heckman EJ, Karjadi C, Ang T, Au R. Digital sleep measures and white matter health in the Framingham Heart Study. Explor Med 2021; 2: 256-267. DOI: 10.37349/emed.2021.00045
Impaired sleep quality and oxygenation are common sleep pathologies. This study assessed the impact of these abnormalities on brain white matter (WM) integrity in an epidemiological cohort, the Framingham Heart Study. Magnetic resonance imaging (MRI) was used to assess WM integrity and wearable digital devices to assess sleep quality.
Stable sleep is positively associated with WM health; increased fractional anisotropy (FA), p=0.03 and decreased mean diffusivity (MD), p=0.01. The sleep fragmenting biomarker, periodicity (eLFCNB) was associated with reduced FA p=0.05 and increased MD p=0.0046.
Healthy brain aging is dependent on the integrity of both grey and WM. Sleep pathology-related mechanisms can cause direct injury to the brain, especially the WM tracts and increase the risk of “WM dementia”. Sleep quality assessed by a novel digital analysis and sleep hypoxia was associated with WM injury. As sleep pathology is highly treatable and diagnostic assessments increasingly are easy to access and minimally burdensome for patients, targeting sleep to improve brain health could be considered at the population level.