[Delirium in elderly inpatients. An 18 month follow-up].

Delirium usually hardens care during hospitalization and increases morbidity during hospital stay and after discharge. The objective of this study was to describe the prevalence of delirium in elderly inpatients in a Buenos Aires hospital, its morbidity and mortality during hospital stay and the next 18 month follow-up. Patients aged 70 or older admitted to internal medicine unit between September 2005 and May 2006 were enrolled. Delirium was assessed with the Spanish version of Confusion Assessment Method. Demographic data, cause of admition and length of stay, destination after discharge and mortality were registered. A new evaluation was made 18 months after discharge. We evaluated 194 patients and 74 were excluded. Of the 120 included, 52 (43.3%) presented delirium. We found significant differences between patients with and without delirium in previous placement in nursing home (17.3% vs. 1.5%; p < 0.002), dementia (40.4% vs. 8.8%; p < 0.001), median activity of daily living (5 vs. 6; p < 0.001), length-of-stay (7 vs. 5; p = 0.04) and mortality rate (21.2% vs. 1.5%; p < 0.001). Evaluation 18 months later showed differences between patients with and without delirium in median of activity of daily living (1/6 vs. 5/6), patients living in nursing homes (27.5% vs. 7.9%), estimated survival 35.3% (CI 95%: 24-49%) at day 569 and 49% (CI 95%: 32.9-65.4%) at day 644. The difference between survival curves was statistically significant (p = 0.027). Delirium increases morbidity and mortality during hospital stay. Elderly with delirium are at risk of worsening disability and of becoming dependent after discharge and it is a risk factor for higher mortality during the following months after discharge.