Comparative Evaluation of Metabolic, Cardiovascular, and Radiological Parameters in Alzheimer’s Disease and Vascular Dementia Patients with and without Type 2 Diabetes Mellitus

Background: Dementia, including Alzheimer’s disease and vascular dementia, is a growing global health concern. Type 2 diabetes mellitus (T2DM) increases the risk of dementia, yet the mechanisms linking these conditions remain unclear. This study evaluates metabolic, cardiovascular, cognitive, and radiological differences in dementia patients with and without T2DM. Methods: A cross-sectional study was conducted at a tertiary care hospital, involving 60 dementia patients (30 with T2DM and 30 without T2DM). Metabolic markers (blood glucose, glycated hemoglobin, lipid profile, and C-reactive protein [CRP]), cardiovascular parameters (blood pressure and electrocardiogram findings), cognitive performance (Mini-Mental State Examination [MMSE] and Montreal Cognitive Assessment [MoCA]), and brain structure changes (magnetic resonance imaging [MRI]-based atrophy scales) were assessed. Results: Dementia patients with T2DM exhibited significantly higher body mass index, waist-to-hip ratio, low-density lipoprotein, triglycerides, and CRP levels compared to non-T2DM patients ( P < 0.001). Cognitive impairment was more severe in the T2DM group, with lower MMSE ( P = 0.004) and MoCA scores ( P < 0.001). MRI findings revealed greater medial temporal atrophy ( P = 0.002) and parietal atrophy ( P = 0.008) in T2DM dementia patients, while non-T2DM dementia patients exhibited more severe white matter lesions ( P = 0.008). Regression analysis identified CRP as the strongest predictor of cognitive function (β = −0.4783, P < 0.001), with glycated hemoglobin showing a near-significant association with MMSE ( P = 0.052). Conclusion: T2DM in dementia is linked to greater metabolic dysfunction, inflammation, and cortical atrophy, leading to greater impairment in cognitive function. CRP was the strongest predictor, highlighting inflammation as a key therapeutic target.