Factors associated with length of hospitalization among people with serious mental illness

Background: Prior studies has documented that length of hospitalization is associated with clinical and socio-demographic characteristics of patients (Spencer et al., 2008). Little is known about the association between facility characteristics and length of hospitalization. This study examines the extent to which facility factors affect length of hospitalization among people with serious mental illness (SMI).

Methods: Pennsylvania Inpatient Discharge Data and American Hospital Association data from 2006 was obtained. The sample consisted of 46,211 adults with SMI (Schizophrenia and Affective Disorders) from 111 inpatient facilities in Pennsylvania. Diagnosis was obtained from ICD-9 codes on discharge records. Regression models, which included patient, facility, and regional characteristics, were employed to explain differences in length of stay.

Results: About 26% of the sample had more than one discharge during the 2006 study period (n = 12,539). The sample had on average 11 days (SD = 6.4) of hospitalization. People with schizophrenia stayed longer than people with affective disorders (15.5 days vs. 8.7 days, respectively). Results from the regression models showed that facilities having a greater number of discharges had on average longer lengths of stay (b=0.62, p<.0001). Furthermore, Medicare recipients were more likely to stay longer than other payer groups (p<.001). The model explained 73% of the variance in length of stay.

Conclusion: Length of hospitalization among people with SMI is related to the total number of facility discharges (which is related to the size of the facility) and payer type.