Unrecognized delirium is prevalent among older patients admitted to general medical wards and lead to higher mortality rate

Abstract

© 2016, Medical Association of Thailand. All rights reserved. Objective: Delirium is a syndrome associated with high mortality that often goes undetected by healthcare providers. There has been limited evidence regarding the consequences of under-recognition of delirium on patient outcomes. The present study aimed to investigate the rate of under-recognized delirium and explore the effect of unrecognized delirium on patient mortality. Material and Method: A cohort of older patients aged 70 years or more who developed delirium during admittance to general medical wards at Siriraj Hospital between January and March 2009 was retrospectively investigated. A diagnosis of delirium was made by geriatricians applying DSM-IV criteria. Medical records were reviewed to identify recognition of delirium by physicians and nurses. Factors affecting mortality were investigated using univariate and multivariate logistic regression models. Results: Of 110 patients who developed delirium, 57.3% of cases were identified as delirium by physicians, with only 14.5% of cases having their delirium documented in the discharge summary. Rate of delirium recognition among nurses was 61.8%, with a comprehensive nursing care plan developed in only 13.6% of cases. Patients with delirium that went unrecognized by attending physicians had a mortality rate of 38.3%, compared to 15.9% for the recognized delirium group (p = 0.008). In multivariate analysis, unrecognized delirium was identified as an independent risk factor for death with adjusted OR of 5.16 (95% CI 1.45-18.29). Conclusion: Rate of unrecognized delirium by healthcare providers in this study was high, but comparable to previous studies. Moreover, under-recognition of delirium was found to lead to higher mortality. Routine screening for delirium and implementation of a proactive care plan by nurses for older patients admitted to general medical wards might be a strategy for improving this common and preventable medical condition and for lowering delirium-related mortality rates.