[Review of functional impairment associated with acute illness in the elderly].

Hospitalization is a risk for elderly population, with a high probability of having adverse events. The most important one is functional impairment, due to its high prevalence and the serious impact it has on the quality of life. The main risk factors for functional decline associated with hospitalization are, age, immobility, cognitive impairment, and functional status prior to admission. It is necessary to detect patients at risk in order to implement the necessary actions to prevent this deterioration, with physical exercise and multidisciplinary geriatric care being the most important.