Protocol for the Babybreathe trial (A randomised controlled trial of a complex intervention to prevent return to smoking postpartum)

Conference:

SAPC ASM 2020 - cancelled due to pandemic

Talk Code:

F.7

Presenter:

Tess Harris

Co-authors:

Caitlin Notley, Linda Bauld, Michael Ussher, Richard Holland, Felix Naughton, Wendy Hardeman, Dan Smith, Allan Clarke, David Turner, Sharon Duneclift, Vicky Gilroy.

Author institutions:

St George's University of London, University of East Anglia, University of Edinburgh, University of Stirling, University of Leicester, Cambridge Community Services NHS Trust, Institute of Health Visiting

Problem

22% of women report smoking in the year before pregnancy. Around half quit smoking during pregnancy, but up to 76% return to smoking within 6 months. There is currently no routine support preventing relapse. Sustained smoking abstinence has significant health benefits for mothers, minimising long-term smoking harm. Furthermore, maternal smoking is the primary source of infant/child second hand smoke exposure and a substantial cause of child morbidity and mortality. “BabyBreathe” successfully developed by our team through an MRC PHIND project, is a novel, complex intervention, offering a combination of face-to-face, digital and tailored support to postpartum women. Study aim: to undertake a randomised controlled trial (RCT) with internal pilot, comparing BabyBreathe with usual care, assessing long-term smoking abstinence for mothers who have recently given birth and have stopped smoking during pregnancy, or during the 12 months prior to pregnancy.

Approach

The study design is an RCT with internal pilot trial, including economic evaluation and process evaluation. We will recruit 880 pregnant women who quit smoking for or during pregnancy identified through their routine midwife or health visitor appointments across four areas of the UK (Norfolk, London, Scotland, the North East). We will run an internal pilot study, with clear stop/go criteria, to test recruitment systems. We will definitively test the real-world effectiveness of BabyBreathe intervention in comparison with usual care, by comparing smoking abstinence at 12-month follow-up between trial groups. We will undertake a cost-effectiveness analysis of BabyBreathe in comparison with usual care, based on healthcare resource use of mother and infant (from NHS, social care and broader family perspectives) and health related quality of life. We will undertake a mixed-methods process evaluation to assess delivery, implementation, fidelity and contamination and to identify mechanisms of action, by exploring which intervention components may be particularly effective, for which women, in which contexts.

Findings

Trial start date Spring / Summer 2020, total duration 39 month: 3m study set up, 15m recruitment, 12-15m follow-up; 6m analysis and dissemination. Details around planned recruitment strategies and intervention delivery will be shared.

Consequences

As a definitive trial, the short-term anticipated impact if the intervention is found to be effective and cost-effective, will be recommendations for change in healthcare policy and practice for supporting postpartum relapse prevention. The anticipated impact of our intervention will be significant improvements in smoking relapse rates, resulting in improved health outcomes for mothers, increased smoking cessation for partners and reduced second-hand smoke for babies and families.

Submitted by:

Teresa J. Harris

Funding acknowledgement:

Public Health Research Programme, National Institute for Health Research