Related Experiment Video
Updated: Jul 30, 2026

An Unpredictable Chronic Mild Stress Protocol for Instigating Depressive Symptoms, Behavioral Changes and Negative Health Outcomes in Rodents
Published on: December 2, 2015
A five-year study on the interactive effects of depression and physical illness on psychiatric unit length of stay
D M Sloan1, J Yokley, H Gottesman
1Department of Psychology, Case Western Reserve University, Cleveland, Ohio, USA.
Objective:
Previous research has shown that hospital length of stay among medical patients is significantly increased by comorbid mental illness, in particular depression. However, few studies have examined the length of stay effect of comorbid physical and mental illness among psychiatric patients.
Method:
The present study examined the effect of comorbid physical and psychiatric illness on hospital length of stay among 2323 psychiatric inpatient admissions over a 5-year period. Patients were grouped into seven diagnostic categories.
Results:
Average length of stay was significantly longer for patients with comorbid physical diagnoses (mean = 20.01 days) than for patients with no physical diagnoses (mean = 16.63 days). Analyses of the psychiatric categories revealed that the average length of stay for depressed patients was significantly greater for those with comorbid physical diagnoses (mean = 19.73 days) than for depressed patients with no comorbid physical diagnoses (mean = 13.96 days). No other psychiatric group evidenced a significant increase in length of stay for comorbid physical illness.
Conclusions:
Results suggest that comorbid physical diagnosis increases length of stay among psychiatric patients overall, with increased hospitalization stay for depressed patients, in particular.
Related Concept Videos
Dimensions of Health and Illness
Classification of Illness
An illness is a response to a disease in which the person's level of functioning is changed compared with a previous level. The general classification of illness includes acute and chronic.
Acute illness is severe and...
Depressive Disorders: Etiology
Biological Factors in Depression
Biological predispositions significantly influence the risk of developing depressive disorders. Genetic studies highlight the role of variations in the serotonin transporter...

