Residential facilities are increasingly used as a resource for dependent older adults and a high percentage of patients with dementia die there. Information about the leading medical causes and exposures to risk factors of mortality in institutionalized older patients with dementia could guide the development of clinical management interventions. The data of 387 institutionalized adults aged over 60, diagnosed with dementia, was analyzed retrospectively. Information about sociodemographic, comorbidities, quality of life and leisure and free time variables was collected in a survey answered by caregivers; after 19 months, information was collected on the result variable (living vs. deceased). A multivariate logistic regression model was created to determine the factors associated with mortality, which were: age (odds ratio (OR)=1.986; 95% confidence interval (CI): 1.229–3.209); diabetes (OR=2.322; 1.350–3.996); hypertension (OR=1.695; 1.044–2.752); diseases of the genitourinary system (OR=2.455;1.419–4.248), worsening of health over last twelve months (OR=1.653; 1.018–2.685) and not performing passive (OR=1.616; 0.968–2.700) or social (OR=2.242; 1.170–4.299) leisure activities. Besides age, the number of comorbid illnesses and the inability to perform leisure activities predicted mortality in institutionalized adults with dementia. These predictors might be useful clinical markers for identifying patients at increased risk for mortality.