Cost-Effectiveness of Financial Incentives to Promote Adherence to Depot Antipsychotic Medication: Economic Evaluation of a Cluster-Randomised Controlled Trial

• Published in: PloS one 2015-10, Vol.10 (10), p.e0138816-e0138816
• Main Authors: Henderson, Catherine, Knapp, Martin, Yeeles, Ksenija, Bremner, Stephen, Eldridge, Sandra, David, Anthony S, O'Connell, Nicola, Burns, Tom, Priebe, Stefan
• Format: Article
• Language: English
• Subjects: Adhesion; Analysis; Antipsychotic agents; Antipsychotic Agents - economics; Antipsychotic Agents - therapeutic use; Antipsychotics; Bipolar disorder; Care and treatment; Clusters; Cost analysis; Cost-Benefit Analysis; Costs; Data collection; Dentistry; Drugs; Economic incentives; Economics; Evaluation; Female; Health care; Health care costs; Health services; Humans; Incentives; Intervention; Life assessment; Male; Medical ethics; Medication Adherence; Mental disorders; Mental health care; Monetary incentives; Motivation; Neurosciences; Patient compliance; Patients; Political science; Primary care; Psychiatry; Psychosis; Psychotic Disorders - drug therapy; Psychotropic drugs; Public health; Randomization; Randomized Controlled Trials as Topic; Schizophrenia; Studies; Substance abuse treatment; Teams
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0138816

Offering a modest financial incentive to people with psychosis can promote adherence to depot antipsychotic medication, but the cost-effectiveness of this approach has not been examined. Economic evaluation within a pragmatic cluster-randomised controlled trial. 141 patients under the care of 73 teams (clusters) were randomised to intervention or control; 138 patients with diagnoses of schizophrenia, schizo-affective disorder or bipolar disorder participated. Intervention participants received £15 per depot injection over 12 months, additional to usual acute, mental and community primary health services. The control group received usual health services. Main outcome measures: incremental cost per 20% increase in adherence to depot antipsychotic medication; incremental cost of 'good' adherence (defined as taking at least 95% of the prescribed number of depot medications over the intervention period). Economic and outcome data for baseline and 12-month follow-up were available for 117 participants. The adjusted difference in adherence between groups was 12.2% (73.4% control vs. 85.6% intervention); the adjusted costs difference was £598 (95% CI -£4,533, £5,730). The extra cost per patient to increase adherence to depot medications by 20% was £982 (95% CI -£8,020, £14,000). The extra cost per patient of achieving 'good' adherence was £2,950 (CI -£19,400, £27,800). Probability of cost-effectiveness exceeded 97.5% at willingness-to-pay values of £14,000 for a 20% increase in adherence and £27,800 for good adherence. Offering a modest financial incentive to people with psychosis is cost-effective in promoting adherence to depot antipsychotic medication. Direct healthcare costs (including costs of the financial incentive) are unlikely to be increased by this intervention. ISRCTN.com 77769281.