Swallowing interventions for the treatment of dysphagia after head and neck cancer: a systematic review of behavioural strategies used to promote patient adherence to swallowing exercises

Govender et al. BMC Cancer (2017) 17:43 DOI 10.1186/s12885-016-2990-x RESEARCH ARTICLE Open Access Swallowing interventions for the treatment of dysphagia after head and neck cancer: a systematic review of behavioural strategies used to promote patient adherence to swallowing exercises Roganie Govender1* , Christina H. Smith2, Stuart A. Taylor3, Helen Barratt4 and Benjamin Gardner5 Abstract Background: Dysphagia is a significant side-effect following treatment for head and neck cancers, yet poor adherence to swallowing exercises is frequently reported in intervention studies. Behaviour change techniques (BCTs) can be used to improve adherence, but no review to date has described the techniques or indicated which may be more associated with improved swallowing outcomes. Methods: A systematic review was conducted to identify behavioural strategies in swallowing interventions, and to explore any relationships between these strategies and intervention effects. Randomised and quasi-randomised studies of head and neck cancer patients were included. Behavioural interventions to improve swallowing were eligible provided a valid measure of swallowing function was reported. A validated and comprehensive list of 93 discrete BCTs was used to code interventions. Analysis was conducted via a structured synthesis approach. Results: Fifteen studies (8 randomised) were included, and 20 different BCTs were each identified in at least one intervention. The BCTs identified in almost all interventions were: instruction on how to perform the behavior, setting behavioural goals and action planning. The BCTs that occurred more frequently in effective interventions, were: practical social support, behavioural practice, self-monitoring of behaviour and credible source for example a skilled clinician delivering the intervention. The presence of identical BCTs in comparator groups may diminish effects. Conclusions: Swallowing interventions feature multiple components that may potentially impact outcomes. This review maps the behavioural components of reported interventions and provides a method to consistently describe these components going forward. Future work may seek to test the most effective BCTs, to inform optimisation of swallowing interventions. Keywords: Dysphagia, Head neck cancer, Swallowing exercises, Behavior change techniques, Adherence, Complex interventions * Correspondence: 1 University College London, Health Behaviour Research Centre & University College London Hospital, Head & Neck Cancer Centre, Ground Floor Central, 250 Euston Road, London NW1 2PQ, UK Full list of author information is available at the end of the article © The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Govender et al. BMC Cancer (2017) 17:43 Page 2 of 15 Background Swallowing difficulties (dysphagia), which affect 60 –75% of patients treated for head and neck cancer (HNC) [1], arise both from the presence of a tumour, and as a consequence of its treatment [2]. Dysphagia is a major patient concern after cancer treatment due to the detrimental impact on patients’ quality of life (QOL) [3]. Improvement of swallowing function and earlier restoration of eating and drinking after surgery or chemoradiation treatments may be achieved with swallowing rehabilitation exercises [4, 5]. Despite this, nonadherence to swallowing exercises in this population is reported to be high [6]. The World Health Organization report defines patient adherence as “the extent to which a person’s behaviour corresponds with agreed recommendations from a health care provider” [7]. This report highlights that adherence is influenced by multiple factors, and that increasing adherence to treatment could have a greater impact on health than trying to improve the efficacy of the treatment to which patients are encouraged to adhere. Adopting this perspective transforms the concept of patient adherence from a peripheral marker of study quality into a concept central to the intervention. The Medical Research Council’s “complex intervention” guidelines highlight that multiple components at different levels may interact to bring about desired health outcomes [8]. Effectiveness of swallowing exercise interventions are determined not just by the exercises but also the broader ‘behaviours of those delivering and receiving the intervention’ (p.979). Complex interventions that take place as pragmatic trials under real-world conditions [9] are influenced by context factors; PROBLEM High prevalence of dysphagia after HNC treatments. GOAL Optimise post-treatment swallowing function. IMPLEMENTATION • • Policy-Patients seen as part of a multidisciplinary cancer care pathway. Health Care System how interventions are implemented (where, by whom) and how patients may respond to this (uptake/adherence) [10]. Newer paradigms in systematic reviewing such as realist reviews focus on understanding how and why interventions work in some situations and not others, rather than simply investigating whether they do or do not work [11]. Sutcliffe and colleagues [12] argue the importance of recognising and identifying the critical components of complex interventions highlighting that outcomes of complex interventions cannot be solely ascribed to the primary content, in this case swallowing exercises. Traditional systematic reviews that focus exclusively on pooling effect sizes may overlook other aspects that influence outcomes. This limits our ability to differentially examine the evidence and to gather important information that may improve future interventions. The system in which the intervention takes place and the possible interactions that may occur can be represented as a logic model [13] (Fig. 1). Swallowing exercise interventions for patients with HNC are normally implemented by trained professionals such as speech therapists within a healthcare setting, and as part of a wider cancer care pathway. The content of the intervention tends to be focused on type, timing and intensity of different swallowing exercises. Accordingly, previous reviews have been largely concerned with these exercise parameters. Langmore and Pisegna [14] suggest that exercises such as the Shaker (head lift exercise) and Mendelsohn manoeuvre (larynx elevation exercise) have good efficacy in improving swallowing function. A general review of interventions to improve eating and drinking after HNC [15] concluded PARTICIPANTS: Patient (...truncated)