Predictors of in-hospital mortality among older patients.

OBJECTIVE: The objective of this study was to determine predictors of in-hospital mortality among older patients admitted to a geriatric care unit. INTRODUCTION: The growing number of older individuals among hospitalized patients demands a thorough investigation of the factors that contribute to their mortality. METHODS: This was a prospective observational study implemented from February 2004 to October 2007 in a tertiary university hospital. A consecutive sample of 922 patients was evaluated for possible inclusion in this study. Patients hospitalized for palliative care, those who declined to participate, and those with incomplete data were excluded, resulting in a group of 856 patients aged 60 to 104 years. Bivariate and multivariate analyses were performed to determine associations between in-patient mortality and gender, age, length of stay, number of prescribed medications and diagnoses at admission, history of heart failure, neoplastic disease, immobility syndrome, delirium, infectious disease, and laboratory tests at admission (serum albumin and creatinine). RESULTS: The overall mortality rate was 16.4%. The following factors were associated with higher in-hospital mortality: delirium (OR=4.13, CI=2.65-6.44, P<.001), neoplastic disease (OR=3.38, CI=2.11-5.42, P<.001), serum albumin levels at admission < 3.3 mg/dL (OR=3.23, CI=2.03-5.13, P<.001), serum creatinine levels at admission > or = 1.3 mg/dL (OR=2.39, CI=1.53-3.72, P<.001), history of heart failure (OR=1.97, CI=1.20-3.22, P=.007), immobility (OR=1.84, CI=1.16-2.92, P =.009), and advanced age (OR=1.03, CI=1.01-1.06, P=.019). CONCLUSIONS: This study strengthens the perception of delirium as a mortality predictor among older inpatients. Cancer, immobility, low albumin levels, elevated creatinine levels, history of heart failure and advanced age were also related to higher mortality rates in this population.