Introduction. This study evaluates the progression of dementia and identifies prognostic risk factors for dementia. Methods. A group of 80 Brazilian community residents with dementia (34 with Alzheimer's disease and 46 with vascular dementia) was assessed over the course of 2 years. Data were analyzed with Cox regression survival analysis. Results. The data showed that education predicted cognitive decline (HR = 1.2; P < .05) when analyzed without controlling for vascular risk factors. After the inclusion of vascular risk factors, education (HR = 1.32; P < .05) and hypertension were predictive for cognitive decline (HR = 38; P < .05), and Alzheimer's disease diagnosis was borderline predictive (P = .055). Conclusion. Vascular risk factors interacted with the diagnosis of vascular dementia. Education was a strong predictor of decline.