Hospitalization and Costs Lower with Aripiprazole

San Diego—A retrospective cohort analysis of medical and pharmacy claims data from 24 state Medicaid plans found that schizophrenia patients newly treated with the atypical antipsychotic (AA) aripiprazole had lower hospitalization rates and expenditures compared with other AAs with the exception of olanzapine. The results were presented during a poster session at the Psych Congress meeting. The poster was titled Comparison of Costs and Healthcare Utilization in Patients with Schizophrenia: Analysis of 24 State Medicaid Programs.

The economic burden of treating schizophrenia in the United States is estimated at $62.7 billion, including $22.7 billion in direct healthcare costs. AAs are considered the cornerstone of treatment. The study’s aim was to compare the costs and healthcare utilization of Medicaid patients with schizophrenia who are prescribed aripiprazole, risperidone, quetiapine, olanzapine, or ziprasidone.

The study included 254,619 single-eligible patients 18 to 64 years of age with schizophrenia who initiated new AA therapy from 2001 to 2007. Exclusion criteria included patients initiating on multiple antipsychotics, patients who were dually eligible in Medicaid and Medicare, and patients without continuous eligibility in Medicaid in the 6-month period before the index date and 1 year after the index date.

Patients were followed for 6 months before and 12 months after their first AA prescription. Generalized linear models in an intent-to-treat framework compared outcomes across AAs while factoring in baseline demographics, comorbidities, and disease severity. Aripiprazole was used as the reference drug for all comparisons. Patients taking aripiprazole (n=28,078) were younger, included fewer men, and had lower rates of preindex hospitalization rates versus the comparators. The mean time on treatment ranged from 161 to 190 days among AAs studied.

The primary outcome measures were inpatient and medical (inpatient plus outpatient) costs in the 12-month follow-up period. The rate of hospitalization and emergency department (ED) visits and the number of hospital admissions and ED visits were also assessed.

In the follow-up period, the results showed that hospitalizations occurred in 31.8% of the total patient population and annual costs averaged $6188. Patients taking aripiprazole had significantly lower hospitalization rates (26.8%) versus quetiapine (36.7%), risperidone (32.6%), and ziprasidone (32.1%), but not olanzapine (24.9%). Similar to hospitalization rates, aripiprazole was associated with significantly lower adjusted rates of ED visits and mental-health related visits (54.3% and 49.2%, respectively) compared with other antipsychotics except olanzapine (47.5% and 43.0%, respectively).

Unadjusted patient costs were considerably lower for aripiprazole ($4537) compared with quetiapine ($7281), risperidone ($6510), and ziprasidone ($5536), but not olanzapine ($5078).

Unadjusted total annual medical costs averaged $17,849 for all costs and $11,393 for mental-health related costs. Adjusted costs for patients on aripiprazole ($15,688) were significantly lower than olanzapine ($16,398) and quetiapine ($16,685), but not risperidone ($15,610) or ziprasidone ($15,984). Adjusted mental-health related costs were also lower for aripiprazole ($9846) compared with ziprasidone ($10,038), olanzapine ($10,171), and quetiapine ($10,222), but were $375 higher than for risperidone ($9471).

This study was supported by Bristol-Myers Squibb and Otsuka Pharmaceutical Co., Ltd.