Cerebrovascular diseases in the context of type 2 diabetes mellitus: cognitive impairment and associated brain status and metabolic characteristics

A significant trend in modern medicine is heterogeneous cognitive impairment (CI). The extremely pressing issue of cerebro-metabolic health and CI, especially against the backdrop of type 2 diabetes mellitus (DM2), is currently the focus of neurology. Objective : to evaluate CI, as well as the associated brain status and metabolic characteristics in patients with various manifestations of cerebrovascular disease (CVD) against the background of type 2 diabetes mellitus. Material and methods . Patients with CVD (n=151) were divided into groups depending on the presence or absence of DM2. The first group (n=69; age – 63.0 [58.0; 69.0] years) consisted of patients with CVD combined with DM2. The second group consisted of 82 patients with isolated CVD (age – 62.5 [57.0; 68.0] years). Clinical and neurological examinations, neuropsychological testing, laboratory tests (including assessment of metabolic parameters and calculation of the triglyceride-glucose index – TyG index) and magnetic resonance imaging (MRI) of the brain were performed. Results . The worst cognitive function (CF) assessment results were recorded in patients with CVS and DM2: Montreal Cognitive Assessment (MoCA) score – 25 [23; 26] points versus 27 [25; 28] points (p<0.001), on the Addenbrooke's Cognitive Examination Scale III (ACE-III)– 87 [80; 89] points versus 90 [84; 94] points (p=0.002). During MRI, more significant changes in the form of white matter hyperintensity (WMH) on the Fazekas scale and other neuroimaging patterns were also noted in patients with DM2: Fazekas III brain damage in 23.2% of patients, Fazekas II in 36.2%, Fazekas II–III – in 59.4% (in patients without DM2 – 7.3; 19.5; 26.8% of observations, respectively; p<0,001). In patients with WMH, the presence of DM2 is associated with a decrease in CF: MoCA – 24 [22; 26] points versus 27 [25; 28] points (p=0.013); ACE-III – 87 [80; 89] points versus 92 [84; 95] points (p=0.012). The severity of CI is correlated with the level of TyG index. Combined cerebro-metabolic status (WMH and TyG index ≥4.825) in patients with CVD was accompanied by more severe CI, with 79.2% of individuals having MoCA <26. Conclusion . The combination of CVD and type 2 diabetes mellitus is characterised by an unfavourable cerebro-metabolic status in the form of significant damage to brain tissue and changes in carbohydrate/lipid metabolism parameters (glucose lipotoxicity) and is associated with more pronounced CI.