Real-world clinical and cost-effectiveness of community clozapine initiation: mirror cohort study
Emma Butler, Toby Pillinger, Kirsten Brown, Faith Borgan, Alice May Bowen, Katherine Beck, Enrico D’Ambrosio, Lisa Donaldson, Sameer Jauhar, Stephen J. Kaar, Tiago Reis Marques, Robert A. McCutcheon, Maria Rogdaki, Fiona Gaughran, James H. MacCabe, Rosalind Ramsay, David Taylor, Paul McCrone, Alice Egerton, Oliver Howes
Abstract
Background Clozapine is the only drug licensed for treatment-resistant schizophrenia (TRS) but the real-world clinical and cost-effectiveness of community initiation of clozapine is unclear. Aims The aim was to assess the feasibility and cost-effectiveness of community initiation of clozapine. Method This was a naturalistic study of community patients recommended for clozapine treatment. Results Of 158 patients recommended for clozapine treatment, 88 (56%) patients agreed to clozapine initiation and, of these, 58 (66%) were successfully established on clozapine. The success rate for community initiation was 65.4%; which was not significantly different from that for in-patient initiation (58.82%, χ 2 (1,88) = 0.47, P = 0.49). Following clozapine initiation, there was a significant reduction in median out-patient visits over 1 year (from 24.00 (interquartile range (IQR) = 14.00–41.00) to 13.00 visits (IQR = 5.00–24.00), P < 0.001), and 2 years (from 47.50 visits (IQR = 24.75–71.00) to 22.00 (IQR = 11.00–42.00), P < 0.001), and a 74.71% decrease in psychiatric hospital bed days ( z = −2.50, P = 0.01). Service-use costs decreased (1 year: –£963/patient ( P < 0.001); 2 years: –£1598.10/patient ( P < 0.001). Subanalyses for community-only initiation also showed significant cost reductions (1 year: –£827.40/patient ( P < 0.001); 2 year: –£1668.50/patient ( P < 0.001) relative to costs prior to starting clozapine. Relative to before initiation, symptom severity was improved in patients taking clozapine at discharge (median Positive and Negative Syndrome Scale total score: initial visit: 80 (IQR = 71.00–104.00); discharge visit 50.5 (IQR = 44.75–75.00), P < 0.001) and at 2 year follow-up (Health of Nation Outcome Scales total score median initial visit: 13.00 (IQR = 9.00–15.00); 2 year follow-up: 8.00 (IQR = 3.00–13.00), P = 0.023). Conclusions These findings indicate that community initiation of clozapine is feasible and is associated with significant reductions in costs, service use and symptom severity.