Suicide Prevention in Cancer Patients: Analysis of the Scientific Literature
Introduction
Every year, approximately 800,000 people worldwide die by suicide, meaning that one person is lost to suicide every 40 seconds. These figures are more than 20 times higher when suicide attempts are considered, meaning that a suicide attempt occurs every 2 seconds [1]. Various risk factors for suicide are known. In a meta-analysis conducted by J. C. Franklin and colleagues, 16 categories of predictors of suicide were identified, including physical illness, with cancer representing one of its subcategories [2]. Several sources indicate that cancer is the only physical illness that increases the risk of suicide [3, 4].
Indeed, a cancer diagnosis and the uncertainty surrounding treatment and recovery represent a major challenge for patients and their physical and mental well-being. A study involving patients with various types of cancer found that more than 50% experienced various physical impairments, and as many as 100% of respondents reported experiencing pain [5]. A study by M. R. Gopalan and colleagues revealed that 41.7% of cancer patients had mental disorders [6]. The suffering experienced by cancer patients is further compounded by the fact that most patients with incurable cancer feel that they are a burden to their loved ones [7].
In some cases, a person experiencing severe suffering begins to consider suicide as one possible way of ending that suffering. Statistics on suicidal ideation among cancer patients vary. A Canadian study reported that 6% of patients with cancer had suicidal thoughts [8], compared with 15.3% in a Chinese study [9]. In a Spanish population study involving patients with advanced cancer, the proportion was even higher, at 25.24%.
Various suicide risk factors have been identified among cancer patients, including older age, lower educational level, unmarried status, living in a rural area, comorbid psychiatric disorders, head and neck cancer, lung cancer, stage IV cancer, atheism, and poor functional status [10–13].
It is important to note that cancer is the second leading cause of death worldwide. The number of cancer diagnoses is expected to increase by 70% over the next 2 decades [14]. Studies conducted in various countries indicate that cancer patients have a higher risk of suicide than the general population. One study found that the suicide rate among cancer patients was almost twice that of the general population [10].
For example, a study conducted in Lithuania showed that patients with advanced cancer had a 3-fold higher risk of suicide than the general population, with the greatest risk occurring within 3 months after diagnosis [15]. A study conducted in England found that the risk of suicide among cancer patients was twice that of the general population and remained elevated for as long as 15 years after diagnosis [16].
Given the high prevalence of cancer and the number of suicides associated with it, suicide prevention strategies for cancer patients are necessary to protect this vulnerable group. Evidence-based suicide prevention strategies are available, including psychological and pharmacological treatment of depression, reducing access to means of suicide, and implementing suicide prevention programs in schools [17]. However, strategies specifically intended for cancer patients have not yet been comprehensively analyzed.
The aim of this article is to review the scientific literature addressing suicide prevention among cancer patients and to discuss potential approaches to suicide prevention in this patient population.
Methods
The literature search was conducted in 2 databases: PubMed and the Cochrane Collaboration.
Articles were included in the literature review if they met the following criteria: the article was written in English; the publication date was January 1, 2007 or later; the population examined in the study consisted of cancer patients; and the subject investigated was suicide prevention (Table 1).
A combination of 3 keywords was used for the article search: cancer, suicide, prevention. In the PubMed database, with the Humans restriction applied, 227 articles were identified, of which 18 met the inclusion criteria. Seven articles were identified in the Cochrane Collaboration database, of which 2 were eligible; both duplicated articles identified in PubMed.
After evaluating suicide prevention strategies for the general population [17], additional searches were conducted in both databases using various combinations of the following keywords: cancer, suicide, prevention, education, social, networks, television, screening, screen, access, means, internet, depression, psychotherapy, antidepressants, physical, activity. An additional 39 eligible articles were identified and included in the literature review (Table 1).
Table 1. Criteria
| Criterion | Inclusion Criteria | Exclusion Criteria |
|---|---|---|
| Article publication date | 2007–2017 | Articles published earlier |
| Language | English | Other languages |
| Population examined in the study | Cancer patients | Other study populations |
| Subject investigated in the study | Suicide prevention | Other factors |
Results
Suicide Risk Factors
To implement potential interventions aimed at preventing suicide among cancer patients, it is important to identify suicide risk factors (SRFs). Various SRFs among cancer patients are described in the literature. Based on our analysis of the literature, we identified 2 groups of SRFs. The first group consisted of SRFs that cannot be actively modified or can only be influenced to a limited extent. These factors were further divided into disease-related and non-disease-related factors. The second group consisted of SRFs that can be actively influenced. These factors were divided into physical and psychosocial factors. Through various interventions, reducing the second group of SRFs could also contribute to suicide prevention.
Sociodemographic and Clinical SRFs
Sociodemographic SRFs
Sex. One of the non-modifiable SRFs is sex. Male sex is an SRF both in the general Lithuanian population and among cancer patients [16, 18]. The scientific literature indicates that among individuals with suicidal thoughts, the highest number of suicide attempts occurred among men who had difficulty making decisions regarding treatment and daily activities [8]. It is important to note that although men die by suicide more frequently than women, the risk of suicide increases after a cancer diagnosis in both men and women [15].
Age. Another important SRF among cancer patients is age. Several studies have shown that older age increases the risk of suicide among cancer patients [15, 16, 19]. However, for example, a study of patients with gynecological cancer found that younger age at diagnosis was associated with an increased risk of suicide [20].
Marital Status. It is also important to consider whether a person is married. Scientific studies have shown that unmarried individuals have a higher risk of suicide [12, 16, 21, 22].
Religion. Religiosity is also considered potentially important when assessing SRFs among cancer patients. A study involving 400 cancer patients found a statistically significant association (p=0.01), with higher suicidality among non-religious cancer patients [13].
Other Factors. Suicide risk is also influenced by other sociodemographic factors, such as education, employment status, and place of residence. A higher risk of suicide among cancer patients is associated with lower educational attainment, unemployment, and living in a small town or rural area [12, 21]. Among cancer patients, a correlation has also been identified between being White and a higher risk of suicide [16].
Read more in Onkologija, No. 1 (22), 2018.
Kamilė Pociūtė¹, Giedrė Bulotienė, PhD²
¹ Vilnius University Faculty of Medicine
² National Cancer Institute
