Objective: The authors identified patient characteristics that increased risk of hospital admission among adults with schizophrenia.
Methods: A total of 1,460 participants in the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) clinical trial were followed from the time they began a randomized trial of medication to first schizophrenia-related hospital admission.
Results: In 869 person-years of follow-up, 203 patients were hospitalized. Increased risk of hospital admission was associated with early age (≤ 17 years) of first antipsychotic treatment (adjusted hazard ratio [AHR]=2.16, 95% confidence interval [CI]=1.49-3.11), psychiatric hospitalization in past year (AHR=2.99, CI=2.23-4.00), having had DSM-IV alcohol (AHR=1.56, CI=1.16-2.10) or drug (AHR=1.50, CI=1.13-2.00) use disorders in the past five years, and baseline severe symptoms according to the Clinical Global Impressions Scale (AHR=1.54, CI=1.04-2.27), presence of tardive dyskinesia (AHR=1.55, CI=1.07-2.23), a high score on the positive symptoms subscale of the Positive and Negative Syndrome Scale (AHR=1.52, CI=1.07-2.15), and low social function (AHR=1.45, CI=1.03-2.04). As compared with olanzapine, the drugs quetiapine (AHR=2.14, CI=1.39-3.31), perphenazine (AHR=1.80, CI=1.11-2.94), and ziprasidone (AHR=2.70, CI=1.64-4.44) were associated with increased hospitalization risk. Risperidone was associated with a lower hospitalization risk than quetiapine (AHR=1.50, CI=1.01-2.22) and ziprasidone (AHR=1.89, CI=1.19-3.01).
Conclusions: Efforts to lower hospital admission risk among individuals with schizophrenia should focus on history of early onset, recent inpatient admission, severe positive symptoms, poor social function, high global illness severity, and comorbid substance use disorders and on selection of an appropriate antipsychotic medication.