Background
Preserving autonomy and control at the end of life can be named as one of the last cornerstones of quality of life in situations of unbearable suffering, despite high quality palliative care [
1‐
5]. Between 1958 and 1967 Cicely Saunders achieved improved care and support for the dying patient [
6]. The development in the field of hospice and palliative care has significantly improved the situation of people at the end of life [
7‐
10]. A “good death” at home without pain after a long and fulfilled life, with the dying person being at peace with the environment and having at least some control over the events remains a desire for most people [
4,
11,
12]. However, the final weeks or days in human life still remain the greatest challenge for all persons involved (family members, informal caregivers and professional staff) [
13]. Unbearable suffering, despite palliative and therapeutic possibilities, leads to requests for ending a patient`s life prematurely. Many aspects of suffering have little in common with symptom control or the use of advanced medicine [
14]. Spiritual pain, symptom clusters, bleeding and open wounds, change of body image, social exclusion, and loss of the sense of life are forms of suffering beyond symptom control [
14,
15].
Hence, over the past 20 years voluntary stopping of eating and drinking (VSED) at the end of life has been discussed as one possibility among several to preserve autonomy, to retain control, and to hasten death without infringing the fundamental ethical principles of Western society [
14,
16,
17]. But, the wish to end one’s life prematurely seems to be incomprehensible for people who have never been confronted with unbearable suffering in their family or social environment. Moral conflicts of clinicians and nurses lead to the fact that VSED remains a marginal topic in the field of palliative care [
18‐
20]. In addition, there is the assumption among some healthcare professionals that VSED leads to more suffering and additional strain for the patient [
21]. Furthermore, food intake is associated with a high social value and is considered as a symbol of social participation. Therefore, stopping eating and drinking can be misunderstood by family members as denial [
21]. As Schwarz pointed out: [
22]
“The desire for a hastened death regularly occurs, but such thoughts are frequently kept secret by patients unless clinicians specifically inquire”. But it is not uncommon that terminally ill cancer patients ask their caregivers for assisted or hastened death [
23‐
25]. Within the scientific community and in research the possibility of a hastened death is often not taken into account [
8]. These aspects may explain why VSED has hardly been examined in the past 20 years, but still remains a legal option in some Western societies [
17,
26].
Our understanding of palliative care is based on the definition from the World Health Organization (WHO) [
27,
28]. Against this background, to fully understand what it means to die remains concealed unless we are affected by death [
29]. Professionals have to develop attitudes that will be of help, in a holistic manner, for the persons concerned [
30]. Therefore, not only is symptom control of central importance, but so is protecting the patient’s autonomy and the ability to maintain control as final aspects of quality of life. In the context of professional palliative care, VSED is highly relevant and therefore requires further analysis.
The international perspective shows that options to hasten death have been a political topic only in some countries where VSED is regarded as a legal possibility to hasten death. For example, comprehensive discussions where lead in Oregon (USA) and the Netherlands [
17,
31,
32]. Switzerland can be called a “right-to-die” society [
32]. Commercial organizations such as DIGNITAS (established in 1998) and EXIT (established in 1982) offer assisted suicide to die with dignity. In 2013 personal rights in Switzerland were strengthened by a further amendment. In this context it can be assumed that the topic of assisted suicide will gain relevance in society and healthcare. Despite the long debate about suicide, it is surprising that VSED so far has not been a topic of debate in Swiss society.
Against this background, in 2012 a mapping review was conducted to explore the phenomenon of VSED [
33]. Knowledge about ways to end one’s life prematurely and clarifying the role of VSED helps caregivers respond to patients’ requests in a professional manner. In the context of the “End of Life National Research Programme NRP 67” in Switzerland, the exploration and explanation of VSED is essential as demand is made for increased knowledge in the areas of “dying processes and provision of care”, “decisions, motives and attitudes”, “regulations and proposals for action”, and “cultural concepts and social ideals” [
34]. Analysis of the current scientific knowledge reveals gaps in the existing research. Therefore, it is necessary to conduct a ‘systematic search and review’ in order to use the current scientific knowledge as a basis for further empirical work. The present article is the first ‘systematic search and review’ about VSED.
Methods
A systematic search and review [
35] was performed to give a comprehensive overview about VSED as an option to hasten death in adults with decision-making capacity at the end of life. This includes (1) clarifying the definition, the prevalence and magnitude, and the ethical aspects and moral standards of VSED, (2) exploring the experience of patients, family members and healthcare professionals with VSED, (3) explaining the physiological processes during VSED and (4) identifying accurate interventions for healthcare professionals to support patients during the process of VSED.
We conducted a systematic literature search for English and non-English articles according to the PRISMA guideline [
36] in the following databases: PubMed (1947–2013), EBSCOhost CINAHL (1981–2013) and Ovid PsycINFO (1967–2013). Database searches were completed between October 2012 and March 2013. Prior to that, a pre-search for sensitizing relevant key words was performed independently by two assistants. The PubMed search was developed by one author (NI), checked by a second author (AF), and translated for use in other databases. The PubMed search string can be viewed in Additional file
1. All database search strings contained both controlled vocabulary and free text words representing the concept of VSED at the end of life. An additional search was performed in the internet using Google Scholar. Furthermore, we checked all reference lists of the included articles for additional published research.
Research articles were included if they report on VSED and adults with decision-making capacity at the end of life, as well as family members and healthcare professionals who have experience with VSED. Furthermore, articles met the inclusion criteria if they described the physiological process during VSED and supporting interventions by healthcare professionals. As VSED is an ethically controversial issue, discussion contribution papers were also included. Articles were excluded if they focused on VSED indirectly, referred to patients in vegetative states or patients with an inability to eat and drink because of disease, patients with artificial nutrition, and when VSED was politically motivated (e.g. hunger strikes). Newspaper articles and commentary letters to the editor of journals were also excluded, because they were regarded as information not contributing to our research questions.
Two authors (NI and AF) independently screened the titles and abstracts for eligibility. Full reports were obtained if the abstracts met our inclusion criteria or when no abstract was available. The full-text of relevant articles were read independently by two authors (NI and AF) to check for inclusion. Disagreements were resolved by discussion. Data were primarily extracted by one author (NI) and checked by the second author (AF) using a data extraction sheet classified with respect to design, objective, sample, measures, analysis and results/case description.
Because the included articles used a wide variety of descriptive and quantitative methods, we evaluated them according to general criteria for quantitative research as described by Coughlan et al. [
37]. There was no uniform rating scale and the articles were coded according to two criteria proposed by Whittemore [
38] when using diverse empirical sources: methodological rigour and data relevance on a 2-point scale (1 = low; 2 = high). Based on the data, evaluation articles with low rigour or relevance were not excluded, but rather considered as trends.
Data synthesis was performed in narrative form typically used for ‘a systematic search and review design’ [
35].
Discussion
The aim of this systematic search and review was to gain a comprehensive insight into voluntary stopping of eating and drinking as an option to hasten death in adults with decision-making capacity at the end of life. The intensive examination of the literature shows that the subject under study has been marginally researched and that there is no scientific basis on which VSED could be explained in all of its dimensions. Therefore, recommendations for its practice in the palliative care setting could not be drawn.
One aim of the present study was to clarify the definition and magnitude of VSED. Based on the available literature, a definition could be sketched, but important basic research to precisely depict the subtleties of VSED as a concept in a comprehensive manner is missing. The available articles can indeed be described as heterogeneous and inconclusive. They represent a patchwork rather than a picture. VSED can be defined as an action by a competent, capacitated person, who voluntarily and deliberately chooses to stop eating and drinking with the primary intention to hasten death because unacceptable suffering persists [
14,
20,
31,
41]. But what does it mean if a “capacitated person” at the end of life is experiencing unbearable suffering? The definition of VSED described above seems to be clear, but the difference as compared to other forms of voluntary renunciation of food and fluid intake requires further investigation. Explaining the magnitude of VSED poses a problem as this concept is mainly discussed in the available literature [
17,
19,
20,
43] in the context of active and passive euthanasia. In our analysis it became clear that in the debate on VSED a fine line exists concerning the ethical conflict between respect for patients and beneficence.
In exploring how patients, family members and healthcare professionals experience VSED, it becomes obvious that the most positive aspect of VSED consists in the preservation of the patients’ autonomy and control regarding their own life. As studies in the palliative setting show, the aspects of autonomy and self-control play an increasingly important role [
4,
45]. In addition, there is little evidence that VSED is considered as an alternative way to hasten death among healthcare professionals in palliative and hospice care in Oregon [
19]. Specific conclusions about the significance of VSED from the perspective of patients, family members and healthcare professionals cannot be made at this point as qualitative studies are still missing. However, it is clear in the debate that physicians are not absolutely necessary to perform VSED, but the situation of the target patients for VSED with unbearable suffering necessarily requires palliative care treatment. This is a contradiction in terms, because on the one hand VSED can be performed independently by patients, but on the other hand the persons concerned need intense and excellent medical and palliative care support [
14,
31]. The active discussion on VSED varied depending on the cultural and regional context. Since VSED is regulated legally in Oregon and the Netherlands, this has mainly been considered in these regions. Thus, this leads inevitably to a cross-regional bias. The authors of this study concluded that the decision for hastened death has to be respected if it is not influenced by mental health problems. For this reason VSED can be interpreted as a patient’s decision against life-sustaining measures.
Objective measures of VSED were not possible to assess, because studies on physiological processes during VSED are missing.
Interventions for healthcare professionals to support patients during the process of VSED could not be identified. Contrary to the recommendations in the included articles, we think that the issue of suicide, euthanasia and hastened death should not be regarded as a last-resort option. They have to be discussed early with the affected persons and not in the last days of life. If options of prematurely ending one’s life are known beforehand, VSED is an expression of autonomy and control, and therefore a sign of the patient’s competence.
Limitations
The benefit of this work consists in the fact that it offers the first ‘systematic search and review’ on the topic of VSED. Compared to other reviews, this article provides the basis for further empirical research. The limitation of this review lays less in the methodological execution, but rather the availability of relevant literature. As shown in the results, VSED is nearly unexplored. Since the synthesis of results is mainly based on narrative reviews, case reports and a few survey studies, the results must be treated with caution and potential risk of bias about the topic should be taken into account. From the literature it became clear that the ethical and legal aspects of VSED require a more detailed analysis in the dependence of the respective settings.
Conclusions
The existing evidence concerning VSED at the end-of-life is intertwined by the authors of the included articles to such a degree that a clear and independent appraisal of the available literature cannot be guaranteed. The evidence can be described as continuous interweaving of published articles. In this respect, we conclude that the evidence was artificially reproduced over time through repeated citations of narrative reviews without new insights based on original studies. The demand expressed by Bernat et al. [
16] with regard to phenomenological studies, that is qualitative studies on the subject and a systematic examination of physiological processes during VSED, has hardly been fulfilled. Recommended steps for further research on VSED are:
(1)
Extended qualitative research is needed for theory-building, especially studies based on Grounded Theory. Furthermore, observational studies and qualitative expert interviews based on qualitative theories, as well as representative epidemiological studies, are necessary to determine the extent and distribution of VSED.
(2)
Based on the findings supportive care interventions for patients and family members need to be developed.
(3)
The development of clinical guidelines is required and recommendations should consider cultural and social requirements.
In summary, it can be stated that the importance of VSED for patients is obvious, because they get an additional option to hasten death. VSED reflects all 12 principles of a ‘good death’, which was defined by the Debate of the Age Health and Care Study Group and involves, for example, to be able to retain control of what happens, to be able to leave when it is time to go, or the possibility to say good bye [
4].
Acknowledgements
We thank Prof. Dr. Beate Senn and Dr. Diana Staudacher for reviewing the manuscript and their useful inputs and comments.
Statement of adherence to the PRISMA guidelines
The authors of this article state that they have adhered to the PRISMA guidelines (2009) for systematic reviews and meta-analyses.
Competing interest
The authors declare that they have no competing interests. This research was funded by the Swiss Academy of Medical Sciences and the Käthe Zingg Schwichtenberg Foundation.
Authors’ contributions
The conception and design of the study were made by NI and AF. The manuscript was drafted by NI and AF and critically revised by DB. The final version of the manuscript for submission was approved by NI, DB, and AF.