The impact of clozapine initiation and cessation on psychiatric hospital admissions and bed days: a mirror image cohort study
Clozapine is the most effective medication for the positive symptoms of treatment-refractory schizophrenia. Although clozapine use is associated with fewer admissions, less is known about the impact of clozapine cessation on hospitalisation.
The aims of this study were to investigate whether clozapine-reduced psychiatric inpatient admissions and bed days, and investigate patient factors associated with these changes from a sample of 1906 people commenced on clozapine.
All people commencing clozapine during an acute hospitalisation over a 10-year period in Queensland, Australia, were included in this retrospective cohort study. A mirror image design was used to compare psychiatric bed days and hospitalisations 2 years before and after clozapine treatment, and the impact of clozapine continuation or early cessation. Changes in psychiatric bed days and hospitalisations were analysed using linear regression, adjusting for the duration on clozapine, sex, age, indigenous status, country of origin and time to clozapine commencement.
There was a significant reduction in bed days (29.55 days vs 24.46 days, p < 0.001) and admissions (2.27 vs 1.87 < 0.001) associated with clozapine commencement. This remained significant among clozapine continuers, but not among those with early cessation. Longer duration on clozapine was associated with greater reductions in psychiatric bed days and admissions. Age, sex and time to clozapine commencement, indigeneity and country of origin did not impact outcomes.
Longer clozapine therapy led to a greater reduction in psychiatric bed days and hospitalisations. Early cessation was associated with a return to pre-clozapine levels of bed days and admissions.
KeywordsClozapine Hospitalisation Admission Cessation Schizophrenia Mirror image
Compliance with ethical standards
Ethics approval was granted by the Metro South Human Research Ethics Committee HREC/15/QPAH/400.
Conflict of interest
The authors declare that they have no conflict of interest.
- Galletly C, Castle D, Dark F, Humberstone V, Jablensky A, Killackey E, Kulkarni J, Mcgorry P, Nielssen O, Tran N (2016) Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for the management of schizophrenia and related disorders. Aust N Z J Psychiatry 50:410–472CrossRefGoogle Scholar
- Howes OD, Mccutcheon R, Agid O, De Bartolomeis A, Van Beveren NJ, Birnbaum ML, Bloomfield MA, Bressan RA, Buchanan RW, Carpenter WT, Castle DJ, Citrome L, Daskalakis ZJ, Davidson M, Drake RJ, Dursun S, Ebdrup BH, Elkis H, Falkai P, Fleischacker WW, Gadelha A, Gaughran F, Glenthoj BY, Graff-Guerrero A, Hallak JE, Honer WG, Kennedy J, Kinon BJ, Lawrie SM, Lee J, Leweke FM, Maccabe JH, Mcnabb CB, Meltzer H, Moller HJ, Nakajima S, Pantelis C, Reis Marques T, Remington G, Rossell SL, Russell BR, Siu CO, Suzuki T, Sommer IE, Taylor D, Thomas N, Ucok A, Umbricht D, Walters JT, Kane J, Correll CU (2017) Treatment-resistant schizophrenia: treatment response and resistance in psychosis (TRRIP) working group consensus guidelines on diagnosis and terminology. Am J Psychiatry 174:216–229CrossRefGoogle Scholar