The Physiological and Biochemical Outcomes Associated with a Reflexology Treatment: A Systematic Review

Hindawi Publishing Corporation Evidence-Based Complementary and Alternative Medicine Volume 2014, Article ID 502123, 16 pages http://dx.doi.org/10.1155/2014/502123 Review Article The Physiological and Biochemical Outcomes Associated with a Reflexology Treatment: A Systematic Review J. E. M. McCullough, S. D. Liddle, M. Sinclair, C. Close, and C. M. Hughes Institute of Nursing and Health Research, University of Ulster, Jordanstown Campus, Shore Road, Newtownabbey, County Antrim BT37 0QB, UK Correspondence should be addressed to C. M. Hughes; Received 21 November 2013; Accepted 10 March 2014; Published 5 May 2014 Academic Editor: Peter Mackereth Copyright © 2014 J. E. M. McCullough et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background. Reflexology is one of the top forms of complementary and alternative medicine in the UK and is used for healthcare by a diverse range of people. However, it is offered by few healthcare providers as little scientific evidence is available explaining how it works or any health benefits it may confer. The aim of this review was to assess the current evidence available from reflexology randomised controlled trials (RCTs) that have investigated changes in physiological or biochemical outcomes. Methods. Guidelines from the Cochrane Handbook of Systematic Reviews of Interventions were followed: the following databases were searched from inception to December 2013: AMED, CAM Quest, CINAHL Plus, Cochrane Central Register of Controlled Trials, Embase, Medline Ovid, Proquest, and Pubmed. Risk of bias was assessed independently by two members of the review team and overall strength of the evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation guidelines. Results. Seventeen eligible RCTs met all inclusion criteria. A total of 34 objective outcome measures were analysed. Although twelve studies showed significant changes within the reflexology group, only three studies investigating blood pressure, cardiac index, and salivary amylase resulted in significant between group changes in favour of reflexology. The overall quality of the studies was low. 1. Introduction Reflexology is considered to be a form of complementary and alternative medicine (CAM). CAM refers to treatments used either as an adjunct to, or instead of conventional medical care. The House of Lords Select Committee for Science and Technology [1] has placed reflexology in group two, categorised as therapies used mostly to complement conventional medicine. Its popularity has increased in recent years as the public seek more holistic ways to maintain good health and well-being [2]. In fact CAM is increasingly being considered as a safe and effective way of reducing the causes and impacts of pain and disease. Reflexology is one of the top six forms of CAM used in the UK [3] and, according to a survey by McDonough et al. [4], it is the second most popular form of CAM used in Northern Ireland. In 2007 a national survey in the USA reported that 38% of adults and 12% of children were using some form of CAM [5] and in the same year a Norwegian survey indicated that 5.6% of the population had used reflexology in the preceding twelve months [6]. In support, a national survey carried out in Denmark in 2005 showed that 21% of the population had used reflexology at some point in their lives and 6% had used it within the previous year [7]. In the UK there are thought to be over 40,000 complementary therapists and the sector is expected to grow by over 30% from £213 million in 2009 to £282 million by 2014 [8]. While the general population is spending large sums of money on CAM, health care professionals are reluctant to promote any benefits for such treatments. Reflexology has come under much criticism based predominantly on the dearth of high quality evidence supporting a clear scientific mechanism of action for the treatment. Most of the research carried out in this area has investigated the psychological outcomes from reflexology focusing on qualitative outcomes. Researchers have repeatedly shown that reflexology has a 2 Evidence-Based Complementary and Alternative Medicine Table 1: GRADE evaluation guidelines [29]. Study limitations Inconsistency Indirectness Imprecision Publication bias The quality of the evidence was downgraded if serious study limitations existed such as a lack of allocation concealment, lack of blinding, large loss to follow-up, or randomized trials stopped early for benefit or the selective reporting of outcomes. The quality of the evidence was downgraded if there was inconsistency in the results, for example, if studies showed varying or different effects of the same intervention. The quality of the evidence was downgraded if there was a level of indirectness in the studies, for example, if interventions had not been compared directly to one another or if the studies investigated a restricted version of the main review question in terms of population, intervention, or outcomes. The quality of the evidence was downgraded if the studies were imprecise in any respect, for example, if they included few participants and few events and thus had wide confidence intervals. The quality of the evidence was downgraded if some element of reporting bias was evident, for example, authors failed to report all the outcomes they set out to or perhaps only reported the positive findings of their study. positive effect on quality of life, stress, anxiety, and pain [9– 12]. However, few studies have attempted to correlate these results with any quantitative physiological or biochemical outcomes. To date six literature reviews of reflexology have been carried out [13–18] and three further reviews on reflexology for cancer care [19], pain and fatigue [2], and pain management [11] are also available. None of these have focused specifically on the quantitative aspect of the results available, although the overwhelming opinion from the authors is that there is not enough high quality RCTs to produce significant scientific data for recommending reflexology as an evidencebased treatment option. The exact mechanism of action of reflexology has yet to be confirmed; however, various theories have been proposed and Tiran and Chummun [20] have detailed many of the current theories in their paper. One of the earliest is the haemodynamic theory which suggests that reflexology stimulation enhances blood flow to the corresponding organ or body part [21]. The findings of an investigation using colour Doppler sonography [22] showed a significant effect on blood flow to the kidney during reflexology and an investigation by Jones et al. [3] displayed some evidence to support this theory. Recent research has also indicated that changes in the dermal layer structures and luminosity of the (...truncated)