OBJECTIVE: The authors describe demographic data, the distribution of diagnoses, and comorbid psychoactive substance use in a large sample of patients involuntarily admitted to a psychiatric hospital from multiple crisis centers and explore the relative roles these variables may play in service utilization and admission rates. METHOD: Data on demographic characteristics and comorbid psychoactive substance use in 2,200 consecutive involuntary hospital admissions of 1,755 psychiatric patients were gathered. Pertinent demographic and comorbidity data at first admission for the 1,755 patients, 314 of whom were admitted more than once, were analyzed; then the data for the 1,441 single-admission patients and the data at first admission for the 314 patients who had multiple admissions were compared. Finally, the diagnostic distribution and comorbid psychoactive substance use in all 2,200 admissions were investigated, with attention to a subgroup of 88 high-risk patients (those with three or more admissions) who represented a total of 307 admissions. RESULTS: Specific demographic characteristics were represented in the patient group at a high level of statistical significance. The diagnosis of schizophrenia was significantly overrepresented. Schizophrenia and psychosis not elsewhere classified clustered in the subgroup with a high risk of readmission. CONCLUSIONS: The results suggest a specific profile for the patient with heightened risk of hospital admission: a young, unmarried, African American male who has schizophrenia without comorbid substance abuse. An effect size data analysis identified marital status and a diagnosis of schizophrenia as the variables associated with the greatest likelihood of admission. Unexpectedly, the impact of comorbid psychoactive substance use was relatively modest and showed a uniform distribution among diagnostic groups.Abstract Teaser