Psychiatr Q (2006) 77:203–209
The Impact of Psychiatric Comorbidity on General
Hospital Length of Stay
Sara K. Bressi, M.S.W., Ph.D. ·
Steven C. Marcus, Ph.D. · Phyllis L. Solomon, Ph.D.
Published online: 7 September 2006
Springer Science+Business Media, Inc. 2006
Abstract Medical inpatients often suffer from comorbid psychiatric illness, which has been
shown in previous studies to be associated with longer hospital stays. The present analysis
used a large representative dataset to examine the impact of patient demographic and clinical
characteristics on the relationship between psychiatric comorbidity and hospital length of
stay. Analyses showed the existence of a psychiatric comorbidity predicted longer hospital
stays for medical inpatients. However, in comparison to previous research, this effect was
attenuated in this sample. Patients with mental disorders who were elderly, on Medicare,
and those with schizophrenia or mood disorders were especially at risk for slightly longer
lengths of stay.
Keywords Length of stay
Psychiatric comorbidity among general medical inpatients is common, with prevalence rates
ranging from 15% to 50% [1–3]. Prior research in the U.S. and abroad indicates these patients
incur hospital stays that are two to ten days longer than patients without mental disorders
[4–8]. Unfortunately, these studies are limited because they were based on unrepresentative
samples drawn from mostly academic medical facilities. Some of these studies have iden-
tiﬁed patient groups particularly at risk for increased length of stay, including those with
depression, organic brain syndromes, cognitive impairment, and substance abuse disorders
S. K. Bressi, M.S.W., Ph.D. (
Assistant Professor, Bryn Mawr Graduate School of Social Work and Social Research, 300 Airdale
Road, Bryn Mawr, PA 19010
S. C. Marcus, Ph.D.
Research Associate Professor, University of Pennsylvania, School of Social Policy and Practice
P. L. Solomon, Ph.D.
Professor, University of Pennsylvania, School of Social Policy and Practice, Department of Psychiatry