Researchers have discovered a genetic marker for suicidal ideation. DNA analysis showed that the 102T/C polymorphism in 5-HT2a receptor gene is significantly associated with major depression. In this study, individuals were evaluated using the Hamilton Rating Scale for Depression. Results revealed that persons with a 102C/C genotype scored significantly higher (a high score on item three of the scale indicates suicidal ideation) than did individuals with T/C or T/T genotypes. In addition, serotonin receptor levels did not normalize after the depression was treated successfully (Muller, 2000a). Such findings suggest that individuals may be biologically predisposed to suicidal thoughts, versus the view of suicide as a character flaw. Perhaps if clients knew that their suicidal urges had a genetic component, they might seek help more readily.

Researchers, striving to identify an endocrine basis for suicide, have demonstrated that a dexamethasone suppression test can identify suicide risk. In a clinical study that spanned 15 years, 114 participants initially received 1 milligram of dexamethasone at 11 p.m. on day one, followed by three measurements of serum cortisol on day 2. The researchers looked at death records an average of more than 15 years later to determine the number of suicides in each group. Of the 56 individuals in the cortisol-suppressor group, 45 participants were still alive and 11 were dead, including one suicide. In the cortisol-nonsuppressor group, 40 of the 58 participants were still alive and 18 were dead, including six suicides. Researchers concluded that the participants in the cortisol-nonsuppressor group experienced a hyperarousal of the hypothalamic–pituitary–adrenal (HPA) axis that affected the brain’s ability to modulate stress states. Disturbances in the regulation of anxiety and aggression due to increased levels of cortisol placed the participants at an increased risk for suicide (McNamara, 2004a).

The relationship among serotonin and postsynaptic frontal cortices’ binding sites, 5-HIAA (a metabolite of serotonin normally found in spinal fluid), and serum
cholesterol has been the focus of research studies. Results concluded that the presence of increased binding sites decreases the availability of serotonin for regulation of aggressive behavior. Low fluid levels of 5-HIAA predict short-range suicide risk, thereby supporting the serotonin hypothesis of suicide risk. Low levels of cholesterol suggest low serotonin availability and reduced inhibition of aggressive behavior (Mericle, 1997; Sadock & Sadock, 2003).

Teenage suicide may be associated with abnormalities of protein kinase C. Postmortem brains of teenage suicide victims revealed a significant decrease in protein kinase C activity in the prefrontal cortex and hippocampus compared with postmortem brains of teenagers who were free of psychiatric illness and did not commit suicide. Researchers believe that protein kinase C may be a target for therapeutic intervention in clients with suicidal behavior (Stong, 2004).

Studies show that suicidal behavior is familial, but the risk factors for transmission from parent to child are unclear. Researchers are attempting to clarify the difference between the development of a mood disorder, which tends to run in families, and the development of suicidal behavior. They are investigating genetic data and neurobiologic factors (eg, endophenotypes) believed to precipitate behaviors (eg, impulsive aggression or cortical responses to stress) that result in suicidal behavior (Kennedy, 2004).

Studies also have focused on suicidal behavior among twins and adoptees (Sadock & Sadock, 2003). According to the studies of twins, suicide among identical twins was significantly higher (11.3%) than suicide among fraternal twins (1.8%). A Danish–American adoption study revealed that adoptee suicide victims experiencing a situational crisis or impulsive suicide attempt or both had more biologic relatives who had committed suicide than did members of the control group.

Of all the perceptions we experience, none has more profound significance than the perceptions we hold regarding our view of who we are and how we fit into the world. This internal view of personal existence is called “the self.” According to the Theory of Self, “the self” tries to maximize its own self-esteem, seeks pleasure, and avoids pain. The maintenance, protection, and enhancement of “the self” may be the basic motive for behavior. “The self” takes precedence over the physical body as individuals often sacrifice physical comfort and safety for psychological satisfaction.

In healthy individuals there is a constant assimilation of new ideas and expulsion of old ideas through life. “The self” continuously guards against perceived threats. If “the self” remains in a defense mode, feelings
of disappointment, guilt, shame, depression, or anxiety may occur. Chronic negative feelings result in low self esteem, cognitive distortions, and irrational beliefs. Social psychologists believe suicide occurs when “the self” is unsuccessful at achieving self-actualization or psychological satisfaction (McNamara, 2004b).

The term parasuicide describes individuals who engage in self-inflicted injury or mutilation but usually do not wish to die. Self-inflicted injury is often associated with childhood trauma. It is a coping method used to deal with situations that produce feelings of rejection, anger, helplessness, and guilt. Self-inflicted injury represents an attempt to relieve tension or bear intolerable emotional pain when everything else fails. This behavior may be an attempt to communicate hurt to others, exert control in an out-of-control life, or to experience a pleasurable analgesic effect as opiates are released into the body after trauma (Starr, 2004; Tumolo, 2005).

Clients who self-inflict generally claim to experience no pain and state they are angry at themselves or others. The incidence of self-injury in the psychiatric setting has been estimated to be more than 50 times that of self-injury in the general population. Self-injury occurs in approximately 30% of clients who abuse substances orally and 10% of clients who abuse intravenous substances before admission to a substance-abuse unit (Johnston, 2002; Sadock & Sadock, 2003).

Although controversy exists over its classification (ie, impulse control disorder, mood disorder, obsessive–compulsive disorder, or tic disorder), trichotillomania (TTM), or compulsive hair pulling, is a form of self-injury that may affect as many as 3% of the U.S. population. Compulsive hair pulling affects young children, adolescents, and adults alike. Persons with TTM most often pull hair from the scalp, but may also pull hair from the eyebrows, eyelashes, pubis, and body (Whitaker, Wolf, & Keuthen, 2003). Individuals who exhibit this behavior claim that they experience an increasing sense of tension immediately before pulling out the hair, followed by pleasure, gratification, or relief. Pulling of hair may continue until external events, self-loathing, or soreness intervenes or an elusive “just-right” feeling is achieved. Physical disfigurement and the inability to control one’s behavior can lead to shame and isolation, as well as avoidance of needed health care services. The social consequences to self-esteem resulting from the hair loss may precipitate depression, contribute to the use of alcohol or drugs to cope with feelings, or place the client at risk for suicidal behavior (Buchanan, 2002; King & Scahill, 1998).

Additional psychosocial factors or motives believed to precipitate suicidal behavior have been identified and explained. Briefly summarized, these factors may include:

Euthanasia, defined as a health care provider’s deliberate act to cause a client’s death, and physician-assisted suicide (PAS), defined as the imparting of information or means to enable suicide to occur, have become controversial issues in the health care industry (Sadock & Sadock, 2003). The increase in human longevity, development of modern medical technology, and use of life-support systems have created an ethical dilemma for health care providers who are often confronted with their responsibility to relieve pain and suffering as well as their obligation to preserve life. Nurses who provide palliative care for dying clients have difficulty distinguishing among allowing, hastening, or causing death when their only goal is to help clients die with peace and dignity (Schwartz, 2002).

In 1997, voters in the state of Oregon approved a Death With Dignity Act. This act applies to adults diagnosed with a terminal illness that is expected to cause death within 6 months. It requires a client to make two oral requests and one written request to a physician and to wait at least 15 days after the initial oral request before receiving a prescription for lethal drugs. A second physician’s opinion is required to verify the initial diagnosis; that the client is capable of and did make an informed decision; and that the decision was made voluntarily. Factors affecting client requests in Oregon for assistance with suicide included pain, fatigue, dyspnea, loss of independence, and poor quality of life (Kirk, 1998; Libow, 2000).

Individuals intent on self-destructive behavior are able to obtain information through books such as Final Exit, a 1991 publication by the Hemlock Society. In 1993, the Hemlock Society held a suicide workshop in San Francisco attended by homosexual males infected with the human immunodeficiency virus (HIV). Internet resources also provide information to educate people on how to commit suicide.

Regardless of the situation, nurses are ethically bound to protect clients who are at risk for self-harm, with the assumption that nurses will do nothing to harm or shorten the lives of clients in their care. The question, though, is raised: “Is it ethical to participate in physician-assisted suicide?” Caring for clients who make such a request may conflict with a nurse’s personal moral beliefs. Although a nurse has the right to choose whether to participate, the nurse may not be aware of a client’s request and therefore become an unknowing participant in PAS.

Knowlton (1998) also discusses the controversy of PAS after a survey of surgical and medical residents who were asked questions such as “Should physicians act on patient requests to die, or should they address patient needs through other measures?” and “What factors other than patient suffering influence requests for assisted death?” The conclusion was reached that further investigation is imperative so that care of severely ill clients is derived from explicit clinically and ethically sound principles of medicine and not based on uncertain motive, incorrect information, or prejudicial attitudes.

Libow (2000) discusses an alternative to PAS, the establishment of a palliative care and ethics team. Such a team would be available to help ease the last days of clients and provide support for family members.