Incidence and risk factors of vascular dementia in Thai stroke patients.

BACKGROUND:Besides disability in stroke survivors, vascular cognitive impairment (VCI) can prevent these patients from living independently. The purpose of this study is to look for the incidence and risk factors of vascular dementia in Thai patients with stroke. METHODS:Adults patients with ischemic stroke were prospectively included. Cognitive assessment was performed at 3-6 months after stroke onset. Montreal Cognitive Assessment (MOCA)- Thai version was used to evaluate cognitive function, with the cutoff point of 24/25 of MOCA to define cognitive impairment/normal cognition. Vascular mild cognitive impairment (VMCI) and vascular dementia (VAD) were diagnosed in those with cognitive impairment. Epidemiologic data, Apolipoprotein E (ApoE) status, and stroke characteristics were compared between patients with and without VAD. RESULTS:There were 180 patients with the mean age of 65 years. Median time after stroke onset to have cognitive assessment was 6 months. Ninety patients (50%) had VMCI. VAD was diagnosed in 49 patients (27%). Mean Thai version of mental state examination (TMSE) and MOCA scores in patients with VAD were 20 and 12, respectively. Multivariate analysis showed that older age (OR 4.994, 95%CI 1.602-15.565, p-value = 0.006), lower education (OR 10.306, 95%CI 3.162-33.586, p-value < 0.001), history of stroke (OR 4.959, 95%CI 1.036-23.741, p-value = 0.045) and moderate to severe cerebral white matter lesions (OR 5.555, 95%CI 1.710-18.041, p-value = 0.004) were associated with VAD. ApoE 4 allele was found in 25% of the patients, but the presence did not show any association with the increased risk of VAD. CONCLUSIONS:VAD occurred in 27% of the stroke patients. Older age, low education level, history of stroke, and the presence of moderate to severe white matter lesions were associated with the increased risk of VAD.