Hepatitis C in the Direct Acting Antiviral Era. The Potential for Benefit Wider than a Viral Cure

Abstract

Background & Aims

The introduction of Direct-Acting Antivirals (DAAs) transformed Hepatitis C (HCV) treatment, despite this the uptake of DAAs remains lower than required to meet the WHO 2030 HCV elimination target. The perception of HCV cure as solely a clinical outcome, may explain the reticence to enthusiastically accept DAAs by the key risk group, people who use drugs. Interferon-based treatment was suggested to be able to deliver important outcomes for patients in addition to a viral cure: social redemption, a shift from a stigmatised identity and support for recovery.

The overall aim of this thesis is to consider if simplified DAAs may be able to deliver these transformative outcomes.

Methods

This thesis utilised several research methods to answer the research questions identified.

A scoping review was conducted to map the existing literature on the non-clinical benefits from HCV treatment in relation to a recovery journey. From this review a hypothesis was generated describing the mechanism through which DAAs may deliver on the transformative outcomes observed in the Interferon-era.

The hypothesis that DAAs could support recovery was tested using a quasi-experimental study method. OST prescribing data was used as a surrogate measure of recovery and people receiving DAAs compared to a control group who spontaneously clear the virus.

A systematic review was conducted to consider the types of actions, interventions and treatments that can support a shift from a stigmatised identity and how this knowledge can be applied to HCV care.

Qualitative and observational data was collated, and a thematic analysis undertaken to provide rich data describing the views, meaning, and values of receiving DAA treatment by patients within NHS Tayside.

Finally, the programme of work turned from looking at how HCV treatment can support recovery journeys to consider how recovery networks can be harnessed to reach people for HCV testing. A feasibility study was conducted to investigate if respondent driven sampling (RDS) may be a viable recruitment method to reach a hidden population.

Results

Our scoping review suggests that the key non-clinical outcomes evident in the Interferon-era may be delivered in the age of DAAs through the theoretical construct of the Social Identity Model of Recovery (SIMOR). The review found that identity change is a constituent part of increasing recovery capital.

The quasi-experimental study of real-world outcomes for patients receiving HCV care in NHS Tayside found that DAA treatment may not confer additional recovery benefits and highlights the limit of the current DAA treatment model in terms of recovery journeys.

The systematic review found that social support is an important aspect of a recovery journey and that HCV treatment services should focus on improving links to wider community resources.

This finding was further strengthened in the thematic analysis of qualitative and observational data which found that after treatment with DAAs individuals reduced the number of active users within their social network and reconnected with family members, building recovery capital. However, individuals remained socially isolated in the context of the wider community which further highlights the need for HCV services to support links to community resources to deliver the social inclusion people desire.

Finally, our feasibility study into the viability of using RDS in recovery networks to reach those at historical risk of HCV demonstrated that it is not an effective tool to reach this hidden population.

Conclusions

DAA treatment has the potential to support important non-clinical outcomes. Receiving DAA treatment can provide the opportunity to rebuild relationships, shift social networks and undertake social activities that improve health and wellbeing, building recovery capital. However, no intervention alone can fully deliver these transformations. We need to challenge the way we conceptualise and design HCV pathways of care to consider how to further integrate with wider community supports and services to provide outcomes people who inject drugs desire.

Date of Award	2024
Original language	English
Awarding Institution	University of Dundee
Supervisor	John Dillon (Supervisor) & Andrew Radley (Supervisor)