Although discouraged in available treatment guidelines, combination antipsychotic prescribing (CAP) is a common practice in the treatment of schizophrenia. Patient characteristics may be associated with this type of treatment. A dataset (N = 363) derived from parallel randomised controlled trials was interrogated to identify factors associated with the receipt of CAP, and a logistic regression analysis was used to predict the occurrence of CAP. Significant predictors of CAP were longer illness, low global functioning score and high treatment adherence rating. Co-prescribed patients received a higher combined dose.
Addington, D., Addington, J., Schissel, B. ( 1990) A depression rating scale for schizophrenics. Schizophr Res3: 247-251.
2.
American Psychiatric Association (1994) Diagnostic and Statistical Manual of Mental Disorders, fourth ed (DSM-IV) . Washington, DC: APA .
3.
Barbui, C., Nose, M., Mazzi, M., Thornicroft, G., Schene, A., Becker, T., et al. (2006) Persistence with polypharmacy and excessive dosing in patients with schizophrenia treated in fourEuropean countries. Int Clin Psychopharmacol21: 355-362.
4.
Barnes, T. ( 1989) A rating scale for drug-induced akathisia. Br J Psychiatry154: 672-676.
5.
Bazire, S. ( 2005) Psychotropic Drug Directory. Wiltshire: Five Pin Ltd. Bingefors, K, Isacson, D , Lindström, E ( 2003) Dosage patterns of antipsychotic drugs for the treatment of schizophrenia in Swedish ambulatory clinical practice: a highly individualized therapy. Nord J Psychiatry57: 263-269.
6.
BNF (2007) British National Formulary . London: BMJ Publishing Group.
7.
Botts, S., Hines, H., Littrell, R. ( 2003) Antipsychotic polypharmacy in the ambulatory care setting, 1993-2000. Psychiatr Serv54: 1086.
8.
Chakos, M., Glick, I., Miller, A., Hamner, M.Miller del, D., Patel, J., Tapp, A., Keefe, R., Rosenheck, R. ( 2006) Baseline use of concomitant psychotropic medications to treat schizophrenia in the CATIE trial. Psychiatr Serv57: 1094-1101.
9.
Chong, M-Y., Tan, CH, Fujii, S., Yang, S-Y., Ungvari, GS, Si, T., et al. (2004) Antipsychotic drug prescription for schizophrenia in East Asia: rationale for change. Psychiatry Clin Neurosci58: 61-67.
10.
Correll, C., Kane, J., O’Shea, D., Razi, K., Malhotra, A. ( 2003) Antipsychotic polypharmacy in the treatment of schizophrenia . [abstract] Schizophr Res60: 37.
11.
Correll, C., Frederickson, A., Kane, J., Manu, P. ( 2007) Does antipsychotic polypharmacy increase the risk for metabolic syndrome. Schizophr Res89: 91-100.
12.
Curtis, J., Capp, K. ( 2003) Administration of ’as needed’ psychotropic medication: a retrospective study. Int J Ment Health Nurs12: 229- 234.
13.
Ganguly, R., Kotzan, JA, Miller, LS, Kennedy, K., Martin, BC ( 2004) Prevalence, trends, and factors associated with antipsychotic polypharmacy among Medicaid-eligible schizophrenia patients, 1998- 2000. J Clin Psychiatry65: 1377-1388.
14.
Guy, W. (revised 1976) ECDEU Assessment Manual for Psychopharmacology . Washington: US Govt. Printing Office.
15.
Hamann, J., Ruppert, A., Auby, P., Pugner, K., Kissling, W. ( 2003) Antipsychotic prescribing patterns in Germany: a retrospective analysis using a large outpatient prescription database. Int Clin Psychopharmacol18: 237-242.
16.
Haro, JM, Edgell, ET, Frewer, P., Alonso, J., Jones, PBthe SOHO Study Group (2003) The European Schizophrenia Outpatient Health Outcomes Study: baseline findings across country and treatment. Acta Psychiatr Scand107(Suppl. 416): 7-15.
17.
Harrington, M., Lelliott, P., Paton, C., Okocha, C., Duffett, R., Sensky, T. ( 2002) The results of a multi-centre audit of the prescribing of antipsychotic drugs for in-patients in the UK. Psychiatr Bull26: 414-418.
18.
Haw, C., Stubbs, J. ( 2003) Combined antipsychotics for ‘difficultto-manage’ and forensic patients with schizophrenia: reasons for prescribing and perceived benefits. Psychiatr Bull27: 449-452.
19.
Hayward, P., Chan, N., Kemp, R., Youle, S., David, A. ( 1995) Medication self-management: a preliminary report on an intervention to improve medication compliance. J Ment Health4: 511-517.
20.
Heinrichs, D., Hanlon, T., Carpenter, W. ( 1984) The Quality of Life Scale: an instrument for rating the schizophrenic deficit syndrome. Schizophr Bull10: 388-398.
21.
Hodgson, R., Belgamwar, R. ( 2006) Off-label prescribing by psychiatrists. Psychiatr Bull30: 55-57.
22.
Hogan, T., Awad, A., Eastwood, R. ( 1983) A self-report scale predictive of drug compliance in schizophrenics: reliability and discriminative validity. Psychol Med13: 177-183.
23.
Janssen, B., Weinmann, S., Berger, M., Gaebel, W. ( 2004) Validation of polypharmacy process measures in inpatient schizophrenia care. Schizophr Bull30: 1023-1033.
24.
Jones, PB, Davies, L., Barnes, TRE, Murray, RM, Dunn, G., Hayhurst, KP, et al. (2006) Randomised controlled trial of effect on quality of life of prescription of second generation (atypical) versus first generation antipsychotic drugs in schizophrenia. Arch Gen Psychiatry63: 1079-1087.
25.
Kay, S., Fishbein, A., Opler, L. ( 1987) The Positive and Negative Syndrome Scale (PANSS) for schizophrenia . Schizophr Bull13: 261-276.
26.
Kreyenbuhl, J., Valenstein, M., McCarthy, JF, Ganoczy, D., Blow, FC ( 2006) Long-term combination antipsychotic treatment in VA patients with schizophrenia. Schizophr Res84: 90-99.
27.
Lelliott, P., Paton, C., Harrington, M., Konsolaki, M., Sensky, T., Okocha, C. ( 2002) The influence of patient variables on polypharmacy and combined high dose of antipsychotic drugs prescribed for in-patients. Psychiatr Bull26: 411-414.
28.
Leslie, DL, Rosenheck, RA ( 2001) Use of pharmacy data to assess quality of pharmacotherapy for schizophrenia in a national health care system: individual and facility predictors. Med Care39: 923-933.
29.
Lewis, SW, Barnes, TRE, Davies, L., Murray, RM, Dunn, G., Hayhurst, KP, et al. (2006a) Randomised controlled trial of effect on quality of life of prescription of clozapine versus other second generation (atypical) antipsychotic drugs in resistant schizophrenia. Schizophr Bull32: 715-723.
30.
Lewis, SW, Davies, L., Jones, PJ, Barnes, TRE, Murray, RM, Kerwin, R., Taylor, D., Hayhurst, KP, Markwick, A., Lloyd, H., Dunn, G. ( 2006b) Randomised controlled trials of conventional antipsychotic versus new atypical drugs, and new atypical drugs versus clozapine, in people with schizophrenia responding poorly to, or intolerant of, current drug treatment . Health Technol Assess10: iii-iv, ix-xi, 1-165.
31.
Miller, A. ( 2005) Polypharmacy in schizophrenia: science, art, and fiction . Current Psychosis Ther Rep3: 61-67.
32.
Milton, J., Lawton, J., Smith, M., Buckley, A. ( 1998) Hidden high-dose antipsychotic prescribing: effects of p.r.n. doses. Psychiatr Bull22: 675-677.
33.
Nice (2002a) Guidance on the Use of Newer (atypical) Antipsychotic Drugs for the Treatment of Schizophrenia . London: National Institute for Health & Clinical Excellence.
34.
Nice (2002b) Core Interventions in the Treatment and Management of Schizophrenia in Primary and Secondary Care. London: National Institute for Health & Clinical Excellence.
35.
RCPsych (2006) Consensus statement on high-dose antipsychotic medication. In: Council Report CR138. London: Royal College of Psychiatrists1-51.
36.
Rey, M., Schulz, P., Costa, C., Dick, P., Tissot, R. ( 1989) Guidelines for the dosage of neuroleptics. I: Chlorpromazine equivalents of orally administered neuroleptics. Int Clin Psychopharmacol4: 95-104.
37.
Rijcken, C., Monster, T., Brouwers, J., de Jong-van den Berg, L. ( 2003) Chlorpromazine equivalents versus defined daily doses: how to compare antipsychotic drug doses. J Clin Psychopharmacol23: 657-659.
38.
Schulz, P., Rey, M., Dick, P., Tissot, R. ( 1989) Guidelines for the dosage of neuroleptics. II: Changing from daily oral to long acting injectable neuroleptics. Int Clin Psychopharmacol4: 105-114.
39.
Sim, K., Su, A., Chan, YH, Shinfuku, N., Kua, EH, Tan, CH ( 2004a) Clinical correlates of antipsychotic polytherapy in patients with schizophrenia in Singapore. Psychiatry Clin Neurosci58: 324-329.
40.
Sim, K., Su, A., Fujii, S., Yang, S-Y., Chong, M-Y., Ungvari, GS, et al. (2004b) Antipsychotic polypharmacy in patients with schizophrenia: a multicentre comparative study in East Asia. Br J Clin Pharmacol58: 178-183.
41.
Simpson, G., Angus, J. ( 1970) A rating scale for extrapyramidal side effects . Acta Psychiatr Scand45: 11-19.
42.
SPSS Inc. (2002) SPSS for Windows Release 11.5. Chicago, Ill., US: SPSS Inc.
43.
Tabachnick, B., Fidell, L. ( 1996) Using Multivariate Statistics, third ed. New York: Harper Collins.
44.
Tapp, A., Wood, A., Secrest, L., Erdmann, J., Cubberley, L., Kilzieh, N. ( 2003) Combination antipsychotic therapy in clinical practice . Psychiatr Serv54: 55-59.
45.
Taylor, D., Mace, S., Mir, S., Kerwin, R. ( 2000a) A prescription survey of the use of atypical antipsychotics for hospital inpatients in the United Kingdom. Int J Psychiatry Clin Pract4: 41-46.
46.
Thompson, C. ( 1994) The use of high-dose antipsychotic medication: consensus statement. Br J Psychiatry164: 448-458.
47.
Woods, S. ( 2003) Chlorpromazine equivalent doses for the newer atypical antipsychotics. J Clin Psychiatry64: 663-667.
48.
Yorston, G., Pinney, A. ( 2000) Chlorpromazine equivalents and percentage of British National Formulary maximum recommended dose in patients receiving high-dose antipsychotics . Psychiatr Bull24: 130-132.
49.
Yusufi, BZ, Mukherjee, K., Aitchison, K., Dunn, G., Page, E., Barnes, TRE ( 2005) Inter-rater reliability of the antipsychotic non-neurological side effects scale (ANNSERS). Abstract. Schizophr Bull31: 574.
50.
Yuzda, MSK ( 2000) Combination antipsychotics: what is the evidence . J Inform Pharmacother2: 300-305.
