Cost-Effectiveness of a Specialist Smoking Cessation Package Compared with Standard Smoking Cessation Service for People with Severe Mental Illness in England: A Trial-Based Economic Evaluation From the SCIMITAR+ Study

Abstract

Background: The declining smoking prevalence in the general population is not reflected among people with severe mental illness (SMI) who smoke. Clinically and cost-effective strategies specific to this population are needed. Methods: A pragmatic two-arm parallel group individually randomised controlled trial was carried out to compare an SMI bespoke smoking cessation (BSC) intervention with usual care (UC). Eligible participants were adult smokers with bipolar affective disorder, schizoaffective disorder or schizophrenia and related illnesses from 16 primary care and 21 secondary care mental health sites in England, UK. Simple randomisation was used following a computer-generated random number sequence masking the allocation but it was not concealed post-randomisation. Total costs, including smoking cessation cost, healthcare and social services costs, and quality-adjusted life years (QALYs), derived from EQ-5D-5L, were used to calculate incremental cost-effectiveness ratio at 12 months post-randomisation. Findings: Between October 2015 and December 2016, 261 participants were randomised to UC group, and 265 to BSC group. After adjustment, the mean total costs in BSC group were £270 (95% CI -£1,690 to £1,424) lower than in UC group while the mean QALYs were 0.026 (95% CI -0·008 to 0·045) higher, leading to BSC dominating UC (95% CI -£339,590 to £295,805 per QALY gained). Interpretation: The cost of BSC did not increase overall costs, indicating a positive effect in health, but a longer time horizon is needed to conclude the impact of quitting on costs and health related gains. Trial Registration: The trial registration number is ISRCTN72955454. Funding Statement: National Institute for Health Research Health Technology Assessment Programme (11/136/52). Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: Ethical approval was granted by NRES Committee Yorkshire & The Humber-Leeds East REC (19/03/2015, ref: 15/YH/0051).