Cost Evaluation of Risperidone Compared With Olanzapine Matthew J. Byerly, M.D. Mary Weber, Ph.D. Deean Brooks, B.S. Sara Beth Casey, M.D. Sheila Elliot Jason Hawkins, Pharm.D.
This study evaluated costs associated with risperidone and olanzapine treatment for schizophrenia. Data were collected from the Department of Veterans Affairs computerized database nine months before and nine months after patients began continuous treatment with risperidone (N=23) or olanzapine (N=47). Both agents were associated with significant reductions in psychiatric hospitalization costs. Median increases in Dr. Byerly, Dr. Weber, and Dr. Casey are affiliated with the department of psychiatry of the University of Texas Southwestern Medical Center at Dallas, 5959 Harry Hines Boulevard, Professional Office Building 1, Suite 600, Dallas, Texas 75390-9101 (e-mail,
[email protected]). Ms. Brooks is with the department of psychiatry of the University of Arkansas for Medical Sciences in Little Rock. Ms. Elliot and Dr. Hawkins are with the Department of Veterans Affairs Medical Center in Little Rock. A version of this article was presented at the annual meeting of the American Psychiatric Association held May 15 to 20, 1999, in Washington, D.C. 742
antipsychotic costs were significantly higher for patients treated with olanzapine ($1,892) than for those treated with risperidone ($733). Mean dosages were 3.5 mg per day for the risperidone group and 18 mg per day for the olanzapine group. Although both treatments were associated with similar reductions in costs of psychiatric inpatient and outpatient care, it was significantly less expensive to prescribe risperidone than olanzapine. (Psychiatric Services 54:742–744, 2003)
R
isperidone and olanzapine, the most frequently prescribed antipsychotic medications in the United States, account for 31.1 percent and 25.2 percent, respectively, of all new antipsychotic prescriptions (1). These agents are more expensive than conventional antipsychotics, which restricts their use by some health care agencies. However, the superior efficacy of risperidone and olanzapine may be a factor in the results of studies that indicate cost savings or cost neutrality associated with these
PSYCHIATRIC SERVICES
agents compared with conventional antipsychotics (2,3). Clear differences in the efficacy or tolerability of risperidone compared with olanzapine have yet to be demonstrated. For example, in one study olanzapine was associated with fewer treatment-emergent adverse events than risperidone (4). However, Conley and Mahmoud (5) found that adverse events were more commonly associated with olanzapine treatment during a head-to-head trial when these agents were used at dosages consistent with clinical practice in the United States. It is possible that comparing the costs of treatment will better indicate the relative benefits of the two agents. Few studies have compared costs of the newer antipsychotic medications in a head-to-head manner. In one retrospective study, the average daily acquisition costs varied from $2.91 to $4.31 for risperidone and from $4.22 to $6.29 for olanzapine. No statistical comparisons of these costs were provided, nor were correlations drawn between use of these medications and other health service
♦ http://psychservices.psychiatryonline.org ♦ May 2003 Vol. 54 No. 5
Table 1
Changes in costs for patients treated with either risperidone or olanzapine at a Department of Veterans Affairs medical centera Median change ($) Mean change ($) Risperidone Risperidone
Olanzapine
Type of cost
Mean
SD
Mean
SD
Psychiatric hospitalization Psychiatric outpatient care Antipsychotic treatment
7,809 208 760
14,668 318 440
8,791 193 1,831
22,026 331 1,270
a b
Median 0 192 733
Olanzapine
Lower to upper quartile Median
Lower to upper quartile
pb
–8,422 to 0 0 to 257 378 to 1,076
–19,224 to 0 0 to 321 1,079 to 2,737
ns ns
