Associations of medical comorbidity, psychosis, pain, and capacity with psychiatric hospital length of stay in geriatric inpatients with and without dementia.

ABSTRACT Background: Geriatric psychiatry hospital beds are a limited resource. Our aim was to determine predictors ofhospital length of stay (LOS) for geriatric patients with dementia admitted to inpatient psychiatric beds. Methods: Admission and discharge data from a large urban mental health center, from 2005 to 2010 inclusive,were retrospectively analyzed. Using the resident assessment instrument - mental health (RAI-MH), anassessment that is used to collect demographic and clinical information within 72 hours of hospital admission,169 geriatric patients with dementia were compared with 308 geriatric patients without dementia. Predictorsof hospital LOS were determined using a series of general linear models. Results: A diagnosis of dementia did not predict a longer LOS in this geriatric psychiatry inpatient population.The presence of multiple medical co-morbidities had an inverse relationship to length of hospital LOS – agreater number of co-morbidities predicted a shorter hospital LOS in the group of geriatric patients who haddementia compared to the without dementia study group. The presence of incapacity and positive psychoticsymptoms predicted longer hospital LOS, irrespective of admission group (patients with dementia comparedwith those without). Conversely, pain on admission predicted shorter hospital LOS.