Predictors of Hospital Length and Cost of Stay in a National Sample of Adult Patients with Psychotic Disorders

Background: Psychiatric inpatient admissions are very costly to the health service system and highly distressing to patients diagnosed with schizophrenia. Despite its importance to the service system, no recent study has documented rates of psychiatric hospital admission, nor has current research explored variation in the rates of admission, length of hospital stay and costs of stay. This study uses a nationally representative dataset to identify regional differences in rates of adult acute psychiatric care admissions, length of stay and costs, in the years 2003 to 2011. The relationship between patient-level characteristics, insurance source, and hospital-level characteristics on the length of hospitalization among adult patients was also examined.

Methods: Secondary data analysis included a subsample of 677,684 adult patients with a primary diagnosis of schizophrenia and other psychotic disorder(s) from the 2003 – 2011 Healthcare Cost and Utilization Project’s (HCUP) Nationwide Inpatient Sample (NIS). The nationally representative survey design and census data were used to construct rates of hospitalization in four U.S. geographic regions. Multilevel models examined variation in patients’ hospitalization length of stay and costs in relation to individual-level (age, sex, race, median income, primary payer source, and problem severity) and hospital-level characteristics (geographic region, location, control or ownership, teaching status, and bed size). 

Results: Mean rate of hospitalization was 140 per 100,000 age-adjusted population. Rates differed dramatically by region with the Northeast having a rate of 219 per 100,000, with the Midwest, South, and West having rates of 167, 112, and 122 per 100,000, respectively. Patients’ race and primary payment source were significantly associated with their time and costs of hospitalization.  African American patients had higher rates of admission but shorter length and lower cost of stay.  Longer hospital stay was associated with being Asian and Native American versus white; higher versus lower severity of illness; and use of Medicaid and Medicare versus private insurance. Hospital-level characteristics of region and control/ownership were significantly related to patients’ length and costs of hospitalization, with Northeastern and public hospitals having higher length and cost of stay.  Additional hospital characteristics associated with longer hospital stay included larger bed size, urban location, and public hospital ownership. 

Conclusions and Implications: There are strong regional and payer source differences in the use of hospitalization to treat schizophrenia and other psychotic disorders. Striking are the higher rates and longer lengths of hospitalizations among adults in the Northeast and differences in rates and length of stay for African Americans compared to white patients.  Future research should investigate the appropriateness of acute care service use from an overuse (Northeast) and underuse (South) perspective. Furthermore, public payers and hospitals had longer hospital stay in these restrictive settings, suggesting either underfunding of public community care resources or excessive cost cutting by private providers. These analyses raise important questions for understanding how health reform affects adult acute care use. Further information on examined hospitalization predictors and implications for mental health and hospital policy initiatives will be discussed.