Influence of length of hospital stay on mortality after discharge in older patients with acute medical diseases

OBJECTIVE: To analyse whether hospital length of stay is associated with mortality at six months after discharge in the elderly. METHODS: An observational longitudinal study of patients surviving at hospital discharge. A binary logistic regression analysis was performed to study factors related to extended stay (> 12 days). The relationship between mortality at 6 months and length-of-stay quartiles was studied using a Cox regression analysis. RESULTS: 1180 patients were studied with a mean age of 86.6 years (standard deviation: 6.9). The median length of stay was 8 days (interquartile range: 5-12). Six-month mortality was 26.1%. After adjusting for age, gender, main diagnosis, comorbidity, albumin at admission, functional deterioration at admission and functional and mental status at discharge, hospital stay above the median was associated with mortality at 6 months: 9-12 days, HR=1.79, 95% CI: 1.01-3.14; and > 12 days, HR=2.04, 95% CI: 1.19-3.53. CONCLUSIONS: Prolonged hospital stay is an independent risk factor for mortality at 6 months after discharge.