Multifactorial Approach to Dementia, Multicentric Study

The goal of this observational study is to assess the role of narcisistic personality disorder and life stressful events in conversion rate to dementia, using a three tier approach along three research lines employing subjects with dementia in retrospective assessment, and normal subjects no yet developing demetia in prospective follow up. The main question\[s\] it aims to answer are: * narcisistic personality disorder as risk factor for conversion to dementia * life stressful events as risk factor for conversion to dementia Participants will be assessed with a complete neurocognitive battery, brain images studies, laboratory analysis, and sociodemographic profile, including depression and comorbidities.