Suicide (cont.)

Can the risk for suicide be inherited?

There is growing evidence that familial and genetic factors contribute to the risk for suicidal behavior. Major psychiatric illnesses, including bipolar disorder, major depression, schizophrenia, alcoholism and substance abuse, and certain personality disorders, which run in families, increase the risk for suicidal behavior. This does not mean that suicidal behavior is inevitable for individuals with this family history; it simply means that such persons may be more vulnerable and should take steps to reduce their risk, such as getting evaluation and treatment at the first sign of mental illness.

Does depression increase the risk for suicide?

Although the majority of people who have depression do not die by suicide, having major depression does increase suicide risk compared to people without depression. The risk of death by suicide may, in part, be related to the severity of the depression. New data on depression that has followed people over long periods of time suggests that about 2% of those people ever treated for depression in an outpatient setting will die by suicide. Among those ever treated for depression in an inpatient hospital setting, the rate of death by suicide is twice as high (4%). Those treated for depression as inpatients following suicide ideation or suicide attempts are about three times as likely to die by suicide (6%) as those who were only treated as outpatients. There are also dramatic gender differences in lifetime risk of suicide in depression. Whereas about 7% of men with a lifetime history of depression will die by suicide, only 1% of women with a lifetime history of depression will die by suicide.

Another way of thinking about suicide risk and depression is to examine the lives of people who have died by suicide and see what proportion of them were depressed. From that perspective, it is estimated that about 60% of people who commit suicide have had a mood disorder (e.g., major depression, bipolar disorder, dysthymia). Younger persons who kill themselves often have a substance abuse disorder in addition to being depressed.