Schizophrenia and potentially preventable hospitalizations in the United States: a retrospective cross-sectional study

BACKGROUND: Persons with schizophrenia may face barriers to high quality primary care due to communication difficulties, cognitive impairment, lack of social support, and fragmentation of healthcare delivery services. As a result, this group may be at high risk for ambulatory care sensitive (ACS) hospitalizations, defined as hospitalizations potentially preventable by timely primary care. The goal of this study was to determine if schizophrenia is associated with overall, acute, and chronic ACS hospitalizations in the United States (US). METHODS: We conducted a retrospective cross-sectional study. Hospitalization data for the US were obtained from the Nationwide Inpatient Sample for years 2003–2008. We examined 15,275,337 medical and surgical discharges for adults aged 18–64, 182,423 of which had a secondary diagnosis of schizophrenia. ACS hospitalizations were measured using the Agency for Healthcare Research and Quality’s Prevention Quality Indicators (PQIs). We developed logistic regression models to obtain nationally-weighted odds ratios (OR) for ACS hospitalizations, comparing those with and without a secondary diagnosis of schizophrenia after adjusting for patient, hospitalization, and hospital characteristics. RESULTS: Schizophrenia was associated with increased odds of hospitalization for acute ACS conditions (OR = 1.34; 95% CI: 1.31, 1.38), as well as for chronic ACS conditions characterized by short-term exacerbations. Schizophrenia was associated with decreased odds of hospitalization for diabetes mellitus long-term complications and diabetes-related lower extremity amputation, conditions characterized by long-term deterioration. CONCLUSIONS: Additional research is needed to determine which individual and health systems factors contribute to the increased odds of hospitalization for acute PQIs in schizophrenia.