Suicide is the act of intentionally taking one’s own life. The study of suicide is essential because suicide is so pernicious and claims the lives of numerous people yearly. Those attempting suicide are experiencing a tremendous amount of psychological pain, and are likely to feel a great deal of hopelessness about their future.

Epidemiology of Suicide

Even though suicide in the United States has dropped from the 9th-leading cause of death in 1996 to the 11-leading cause of death in 1999, it remains a persistent problem. More than 30,000 people die each year by suicide, and more than 84 people commit suicide each day. The national rate of suicide is 10.7/100,000, meaning that of every 100,000 people in the United States, 10.7 take their own lives. However, the number of suicides may be underestimated due to underreporting. Suicide is underreported for a number of reasons, including fear of stigma and of legal complications. It can also be difficult to distinguish a suicide from an accidental death.

Although women attempt suicide more often, more men die by suicide. The rate for women is 4.1 /100,000 each year, and the rate for men is nearly four times as much, at 17.6/100,000. This gender difference involves the type of suicide method used. Men tend to use more lethal methods, whereas women are more likely to use less lethal methods, which provide more opportunity for rescue or resuscitation.

In general, the rate of suicide increases with age. The age group that commits the largest number of suicides is that of people 65 years of age and older, at a rate of 15.9/100,000. However, 15- to 24-year-olds are also at high risk; in this age group, suicide is the third-leading cause of death, following only to accidents and homicide. The suicide rate for 15- to 24-year-olds is 10.3/100,000, and every year 4,000 people between the age of 15 and 24 years die by suicide.

The rate of suicide varies among different ethnic groups. In the United States, Whites have substantially higher rates of suicide than African Americans, although the rate for African Americans has been increasing. White men older than 65 years have the highest rate of suicide (37/100,000), and African-American women tend to have the lowest rate (2/100,000). The rate for African-American men has been increasing over time and is 11.4/100,000. Hispanics have a lower rate of suicide than Whites, and the rate for Native Americans tends to vary, but is extremely high in some regions.

Causes and Contributors

No single risk factor causes a person to commit suicide, and people who attempt suicide usually exhibit a number of risk factors. A strong predictor of future suicidal behavior is previous suicidal behavior. People who have attempted suicide before are up to eight times more likely to attempt suicide again. Individuals with a history of suicidal behavior in the family are also at greater risk for suicide, due, in part, to the influence of as-yet-unidentified genes.

There are a number of other risk factors to consider. One is the presence of one or more mental disorders. Many people who die by suicide meet the diagnostic criteria for at least one mental disorder. Disorders that are most associated with suicidal behavior are mood disorders and substance abuse disorders. Personality disorders are also related to an increased risk of suicide. A biological risk factor associated with suicidal behavior is reduced serotonin levels. Serotonin has clearly established links to suicide and is the primary neurotransmitter implicated in suicide risk. Suicidal behavior is also often correlated with cognitive biases or distortions in which people are likely to hold a negative view of the self, the world, and the future. Some people who are suicidal also have deficits in their interpersonal problem-solving skills, impulse control problems, and impaired coping abilities.

Social factors also are related to suicidal behavior. A lack of social support, which may be related to poor social skills, isolation, and loss of relationships, may play a role in the suicidal process. Negative life events are related to suicidal behavior such that suicides are more likely to occur during stressful than nonstressful times. Having close relationships and a supportive environment can be a protective factor against suicide. It has been found that a history of child abuse is related to a greater number of suicide attempts, particularly in adolescence.

Warning Signs and Predictors

The need for assessment of risk in suicide is crucial. By identifying individuals who are at risk for suicide, interventions can be conducted to help prevent a tragedy. As stated previously, a strong predictor of future suicidal behavior is more than one previous suicide attempt. Other considerations that can be easily assessed are whether the person thinks about and desires suicide, and has a plan and has prepared to actually attempt suicide. Individuals who have thought about suicide, but do not have a plan, and have at least two other risk factors as described should be considered at least at moderate risk for suicide. Individuals who have had multiple suicide attempts in the past, or who have a plan and are prepared to attempt suicide, should be considered to be at least at moderate risk in the presence of any additional risk factor. Therefore, when trying to establish an individual’s risk for suicide, it is important to evaluate his or her current suicidal thoughts and plans in addition to all risk factors that may be present.

Preventative Steps and Treatment

With regard to treatment, a solid empirical base does not exist in the suicidality literature. A common treatment approach for a person who is suicidal is hospitalization. However, there is not strong empirical support for the effectiveness of hospitalization. Psychotropic medications are used with some suicidal patients to help stabilize their moods. Many studies indicate that techniques involving cognitive-behavioral therapy and problem solving are safe and effective for suicidal people. Sometimes therapists also work with suicidal clients on skill building and personality development.

Suicide and Chronic Physical Illness

Although it is true that physical illness increases the risk of suicidal behavior, and is in fact a risk factor for suicide, it would be incorrect to assume that having a terminal illness causes suicidality. The majority of people diagnosed with a terminal illness do not attempt suicide. The risk for suicide is elevated among people with particular illnesses. Cancer patients and those with neurological disorders commit the largest number of suicides among the physically ill.

It is not the physical illness that increases people s inclinations to suicidal behavior per se. What is more likely is that the factors associated with a physical illness lead to increased suicidal behavior. These factors can include a number of stressful issues that a patient experiences through the course of an illness. Many people have difficulties before they are diagnosed because they are worried about the possibility of having a disease. Once people are diagnosed, they have to confront the reality that they have a disease and are faced with anxiety about cures, prognosis, and financial issues. After their diagnostic period, many people worry about the success of their treatment and have social problems such as loss of income. These new doubts, fears, and worries could lead to a crisis reaction, possibly precipitating suicidal behavior.

There are a number of other factors associated with an increased risk of suicide among the physically ill. Often it is possible for physical illness to contribute to other physical, psychological, and social problems. Included in these problems are pain, the loss of ability to work, social limitations, and pressure for payment from financial support agencies. When people are ill, they often experience changes in their perceptions of their self and relationships with significant others. These perceptions of changes, as well as actual changes, can also contribute to suicidal behavior.

Suicide kills many every year. In the United States nearly 30,000 people die every year by suicide, with the most at-risk people being White men older than 65 years. Although no single risk factor causes a person to commit suicide, there are a number of risk factors associated with suicidal behavior. These risk factors include age, sex, psychiatric diagnosis, a history of a previous suicide attempt, a history of child abuse, stressful life events, lack of social support, impulsivity, cognitive distortions, and active suicidal thoughts and behaviors. Although some treatments have been found to be helpful for people with suicidal ideations, there is no one reliable treatment that has been proven to be effective. Though the research is limited, cognitive-behavioral therapy is building a reputation as a treatment of choice for suicidal symptoms. Most people with physical illnesses do not commit suicide. However, suicidal behavior is strongly related to physical illness, and is related in particular to cancer and neurological illnesses. The correlation between suicide and physical illness is likely due to the stressors associated with a physical illness as opposed to the physical illness itself.


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