Objective To investigate the influencing factors for vascular dementia (VD) after the first brain infarction attack in middle-aged and elderly patients.Methods A total of 213 patients aged 45-75 years who experienced the first brain infarction attack were enrolled, and according to the cognitive function at 3 months after the attack, these patients were divided into VD group and control group. The two groups were compared in terms of general data and examination results. The univariate and multivariate logistic regression analyses were used to screen out the influencing factors for VD, and the receiver operating characteristic (ROC) curve was used to investigate the diagnostic cut-off values of related indices.Results The logistic regression analysis showed that Hcy (OR=5.921, P<0.001), age (OR=6.030, P<0.001), infarct area (OR=1.372, P<0.001), brain atrophy (OR=5.226, P=0.003), leukodystrophy (OR=1.434, P=0.025), hypertension (OR=2.346, P=0.027), diabetes (OR=2.271, P=0.042), education level (OR=0.195, P<0.001), and rehabilitation exercise after discharge (OR=0.416, P=0.004) were independent influencing factors for VD after cerebral infarction; the cut-off values of Hcy, age, and infarct area were 18.08 μmol/L, 61.1 years and 5.67 cm², respectively.Conclusions In middle-aged and elderly patients experiencing the first brain infarction attack, high Hcy, old age, large infarct area, and comorbidities of brain atrophy, leukodystrophy, hypertension, and diabetes may increase the risk of VD, while high education level and rehabilitation exercise can reduce the incidence of VD.