Cost-effectiveness of a patient-centred approach to managing multimorbidity in primary care: a pragmatic cluster randomised controlled trial

Conference:

SAPC ASM 2018 - London

Talk Code:

5E.1

Presenter:

Joanna C Thorn

Co-authors:

Mei-See Man[1,2], Peter Bower[3], Bruce Guthrie[4], Katherine Chaplin[1], Daisy Gaunt[2], Sara Brookes[2], Bridie Fitzpatrick[5], Caroline Gardner[3], Sandra Hollinghurst[1], Victoria Lee[3], John McLeod[4], Stewart Mercer[5], Chris Salisbury[1]

Author institutions:

[1]Centre for Academic Primary Care University of Bristol, [2]Bristol Randomised Trials Collaboration University of Bristol, [3]Centre for Primary Care University of Manchester, [4]Population Health Sciences Division University of Dundee, [5]Institute of Health and Wellbeing University of Glasgow

Problem

Patients with multiple health conditions are often managed in a disjointed fashion in primary care, with clinic appointments offered separately for each condition. The 3D intervention was developed as a means of improving the system of care; patients receiving the intervention were offered comprehensive review appointments with a named GP, alongside nurse appointments and pharmacist review. This study aimed to determine the cost-effectiveness of the complex 3D intervention.

Approach

Patients with three or more long-term conditions in participating GP practices in three UK sites were randomly assigned to receive the 3D intervention or usual care. A cost–utility study was conducted alongside the 3D effectiveness trial. The EQ-5D-5L health-related quality of life instrument was completed by participants at baseline, 9 months and 15 months post-randomisation, and quality-adjusted life years (QALYs) were derived. Data were collected on the costs of delivering the intervention and training, and the use of health services in primary care, community care, secondary care, and social care for the primary analysis from the perspective of the NHS and personal social services (PSS). All participants were analysed as randomised, with missing data imputed using chained equation multiple imputation methods. Costs and outcomes (both discounted at 3.5% in the final three months) were combined to calculate an incremental cost-effectiveness ratio (ICER), and the probability of the intervention being cost-effective at a range of societal willingness-to-pay thresholds was assessed. Sensitivity analyses excluding participants who died, and using undiscounted costs and outcomes, were conducted to assess the impact of potential sources of uncertainty.

Findings

797 participants were randomised to be offered the 3D intervention, while 749 participants were randomised to receive usual care. Very small increases were found in both QALYs (adjusted mean QALY difference 0.007 [-0.009 to 0.023]) and costs (adjusted mean difference £126 [£-739 to £991]) in the intervention arm from the perspective of the NHS/PSS after 15 months of follow-up. The ICER was £18,499, with a 50.8% chance of being cost-effective at a willingness-to-pay threshold of £20,000 per QALY (55.8% at £30,000 per QALY). The sensitivity analyses suggested similar results.

Consequences

The small differences in costs and outcomes were consistent with chance, and the uncertainty was substantial; therefore, the evidence for the cost-effectiveness of the 3D approach from the NHS/PSS perspective should be considered equivocal and interpreted with caution. Implementation of the intervention is likely to be achieved at relatively low cost, although individual practices may consider that the disruption of setting up a new system outweighs the potential benefits. Given the equivocal nature of the cost-effectiveness results, they should be considered in conjunction with evidence from the participants themselves about satisfaction with the intervention, and with other process outcome measures to inform a decision on implementation.

Submitted by:

Joanna Thorn

Funding acknowledgement:

This project was funded by the National Institute for Health Research Health Services and Delivery Research Programme (project number 12/130/15). The views and opinions expressed in this report are those of the authors and do not necessarily reflect those of the NIHR, the NHS or the Department of Health.