Background: Adults with type 2 diabetes mellitus (T2DM) frequently report poor sleep quality. However, the impact of poor sleep, which may exacerbate brain changes in T2DM patients, is unclear. Study aim was to evaluate sleep symptoms and the relationship between sleep quality and brain changes in T2DM using high-resolution magnetic resonance imaging (MRI) procedures.

Methods: Brain MRI images were collected from 17 T2DM patients (age 55.8 ± 7.0 years, 7 males) and 52 controls (age 55.7 ± 1.8 years, 32 males) using a 3.0-Tesla MRI scanner. Sleep symptoms were assessed with the Pittsburgh Sleep Quality Index (PSQI) and images evaluated using gray matter density (GMD) maps. Statistical analysis included partial correlations and ANCOVA (covariates: age, sex).

Results: T2DM patients showed worse sleep symptoms compared to controls (7.2 ± 4.0 vs. 3.6 ± 2.0; p<0.001). There were negative correlations between GMD (including frontal cortices, hippocampi, and cerebellum) and sleep quality (lower density in persons with higher PSQI/worse sleep) [left cerebellum GMD vs. PSQI, r = -0.742, p = 0.002; right GMD vs. PSQI, r = -0.722, p = 0.002].

Conclusion: Adults with T2DM show reduced GMD negatively correlating with increased sleep disturbance symptoms. Potential mechanisms are unclear, but may involve altered glucose metabolism or hypoxic-induced processes. Efforts to improve sleep quality may help mitigate brain changes in T2DM patients.

C. Cabrera-Mino: None. B. Roy: None. M.A. Woo: None. R. Kumar: None. S.E. Choi: None.


National Institute of Nursing Research (1R01NR017190-01A1)

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