Three-year mortality of delirium among elderly inpatients in consultation–liaison service

ObjectiveThe purpose of this study is to assess 3-year mortality in delirious patients receiving consultation–liaison service in a general hospital setting.MethodsWe consecutively enrolled inpatients 65 years of age and older that were referred for psychiatric consultation (N=614) from 2002 to 2006. One hundred and seventy-two patients were diagnosed with delirium. The exact date of death was based on the registration data from the Department of Health, Executive Yuan, in Taiwan and was used to calculate the mortality rate and time to death (days) after psychiatric consultation. Furthermore, the 1-year, 2-year and 3-year mortality rates of delirious patients were compared to mortality rates of nondelirious patients. Factors (e.g., age, length of hospital stay, gender, physical illness, use of antipsychotics) were analyzed by using the Cox proportional hazard model to identify possible associations with mortality.ResultsDelirious patients had a higher mortality rate each year than nondelirious patients. After analysis, 1-year mortality was significantly higher in the delirious group than in the nondelirious group (P=.043), but 2-year and 3-year mortality rates were not significantly different when comparing the delirious and nondelirious groups (P=.149; P=.439). In the Cox proportional hazard regression analysis, 1-year mortality in delirious patients was significantly associated with older age and length of hospital stay (P<.001), but not with gender, physical comorbidity or use of antipsychotics.ConclusionThese results suggest that elderly delirious inpatients in psychiatric consultation service had significantly higher mortality than nondelirious inpatients, especially in the first year after consultation. Clinical physicians should pay close attention to delirious patients, especially those with mortality-related risk factors, in order to reduce mortality in these patients.