Abstract
Background: Insight into the effect of clozapine is limited by a lack of
controlling for confounding variables in current research. Our objective was
to investigate the association between clozapine prescribed at discharge,
following an inpatient episode, and risk of readmission into secondary
mental health services in patients with schizophrenia and schizoaffective
disorder, controlling extensively for confounding variables.
Methods: Clinical records from 3,651 patients were analysed in a
retrospective observational cohort study. Cox proportional-hazards
regression models were used to assess the risk of hospital readmission. A
series of sensitivity analyses were also conducted. Propensity score
methods were used to address confounding-by-indication.
Results: Patients on clozapine (n=202) had a reduced risk of readmission
compared to patients on other antipsychotics (adjusted hazard ratio=0.79;
95% CI: 0.64-0.99; P=0.043). Clozapine also had a protective effect on
risk of readmission when compared to olanzapine (adjusted hazard ratio 0.76; 95% CI 0.60-0.96; P=0.021). The effect size remained consistent
after adjusting for an array of possible confounders, as well as using
propensity scores to address confounding-by-indication. A statistically
significant result was also noted in all but two sensitivity analyses.
Conclusion: Our findings suggest that clozapine is associated with a
reduced risk of readmission into secondary mental health services.
controlling for confounding variables in current research. Our objective was
to investigate the association between clozapine prescribed at discharge,
following an inpatient episode, and risk of readmission into secondary
mental health services in patients with schizophrenia and schizoaffective
disorder, controlling extensively for confounding variables.
Methods: Clinical records from 3,651 patients were analysed in a
retrospective observational cohort study. Cox proportional-hazards
regression models were used to assess the risk of hospital readmission. A
series of sensitivity analyses were also conducted. Propensity score
methods were used to address confounding-by-indication.
Results: Patients on clozapine (n=202) had a reduced risk of readmission
compared to patients on other antipsychotics (adjusted hazard ratio=0.79;
95% CI: 0.64-0.99; P=0.043). Clozapine also had a protective effect on
risk of readmission when compared to olanzapine (adjusted hazard ratio 0.76; 95% CI 0.60-0.96; P=0.021). The effect size remained consistent
after adjusting for an array of possible confounders, as well as using
propensity scores to address confounding-by-indication. A statistically
significant result was also noted in all but two sensitivity analyses.
Conclusion: Our findings suggest that clozapine is associated with a
reduced risk of readmission into secondary mental health services.
Original language | English |
---|---|
Pages (from-to) | 449-458 |
Number of pages | 10 |
Journal | Journal of Psychopharmacology |
Volume | 33 |
Issue number | 4 |
Early online date | 8 Jan 2019 |
DOIs | |
Publication status | Published - 1 Apr 2019 |
Keywords
- Clozapine
- atypical antipsychotics
- readmission
- schizoaffective disorder
- schizophrenia