To examine risk factors for prolonged hospital length of stay (LOS) in the oldest-old inpatients aged ≥ 90.
This retrospective cross-sectional study was performed in acute Geriatrics Department at Kaplan Medical Center. The target population was the oldest-old inpatients aged ≥ 90 hospitalized with acute illness. In total 1536 admissions of 987 patients admitted between January 2007 and December 2010 from the emergency room were included in the study. We retrieved from the electronic hospital records the following data: demographics, admission diagnosis, comorbidities, laboratory tests, drugs, functional and cognitive status, Charlson Comorbidity Index (CCI) score and age-adjusted CCI score.
The risk factors for a prolonged LOS were tube-feeding, consumption of ≥ 5 drugs, non-independent functional status, diagnosis of urinary tract infection (UTI), pneumonia and malignancy on admission, and comorbidities of congestive heart failure (CHF) and hypoalbuminemia. Multiple linear regression analysis found that UTI, hypoalbuminemia, elevated troponin, pneumonia, number of drugs, malignancy, CHF and number of comorbidities explain a higher risk for a longer LOS.
Hospital LOS in the oldest-old patients in acute geriatric ward was associated with admission diagnosis and comorbidities. Awareness of the risk factors for a longer LOS might contribute to reducing hospitalization stay and its related negative consequences. Accurate prediction of prolonged LOS in this age group of patients may be more challenging and require variables that were not included in our study. Future research is warranted.

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