[Brain tractography in type 1 and 2 diabetes and cognitive impairment]

To study conductive white matter pathways in patients with type 1 and type 2 diabetes with- and without cognitive impairment.

The study included 85 patients with type 1 and 95 patients with type 2 diabetes who were divided into those who had normal cognitive functions and those with cognitive impairment. The groups were comparable in age and duration of the disease. Screening of cognitive functions was performed using the Montreal Scale for the Evaluation of Cognitive Function (MoCA-test). Brain MRI was performed on 1.5 Tesla system. All statistical analyses and data processing were performed using Statistica (Statsoft) software (version 10) on Windows 7/XP Pro operating systems.

The study revealed the prevalence of mild and moderate cognitive impairment in type 1 diabetes, medium and severe in type 2 diabetes, which were mainly manifested by memory, attention and optical-spatial disorders. Intergroup analysis of the brain tractography did not show any difference in the integrity of tracts in type 1 and type 2 diabetes, but the most significant risk factors of pathway impairment were identified. They include arterial hypertension (H=6.602833, p=0.0368), degree of polyneuropathy (H=15.30420, p=0.0005), degree of nephropathy (H=9.993923, p=0.0068), degree of retinopathy (H=8.445891, p=0.0376) for type 1 diabetes and age (H=7.381742, p=0.0607), (H=8.359127, p=0.0391) for type 2 diabetes. Cholesterol level contributes to the risk in both types (H=4.009380, p=0.0452; H=4.057357, p=0.0440; H=6.454558, p=0.0111). The corticospinal and commissural tracts are most susceptible to damage.

There are no significant differences in axial cerebral tract diffusion in patients with type 1 and type 2 diabetes with- and without cognitive impairment. However, the most important risk factors for white matter structure damage, namely, arterial hypertension, diabetic complications, cholesterol levels and age, are verified.