Relation of Family History of Suicide to Suicide Attempts in Alcoholics

In 1983 I reported (1) that, among a consecutive series of 5,845 psychiatric inpatients, a history of attempted suicide was found in significantly more of the 243 patients who had a family history of suicide than in the 5,602 patients who did not have a family history of suicide. A family history of suicide was found to significantly increase the probability of a suicide attempt across psychiatric diagnoses. However, the psychiatric hospital in which that study took place did not have a substance abuse program and did not routinely admit alcoholic patients. Thus, whether a family history of suicide is a risk factor for suicidal behavior in alcoholic patients was not examined in that study and, to my knowledge, has not been reported in the literature. Therefore, the purpose of this study was to examine whether a family history of suicide is associated with attempts at suicide by alcoholics. The hypothesis tested was that a family history of suicide would be significantly more common among alcoholics with a history of attempted suicide than among alcoholics who had never attempted suicide.

Method

The subjects were a consecutive series of 333 alcoholics seen in the Substance Abuse Treatment Program at the Department of Veterans Affairs, New Jersey Health Care System, East Orange Campus; 36 were outpatients, and 297 were inpatients. The inclusion criteria were a DSM-IV diagnosis of alcohol dependence and identification of alcohol as the subject’s drug of first choice. Each patient completed a semistructured interview about sociodemographic variables, lifetime history of attempts at suicide, and completed suicide or attempts at suicide in first- or second-degree relatives. A suicide attempt was defined as a self-destructive act with some intent to end one’s life that was not self-mutilatory in nature and that required medical evaluation. The information from the patient was supplemented by collateral information from medical records and treating mental health professionals. After complete description of the study to the subjects, written informed consent was obtained.

In the statistical analysis the chi-square test with Yates’s correction was used.

Results

Of the 333 alcohol-dependent patients, 124 had attempted suicide at some time and 209 had never attempted suicide. Twenty of the 124 alcoholics who had attempted suicide were female, compared with nine of the 209 who had never attempted suicide (χ²=12.24, df=1, p<0.0001). There was no significant difference for age or marital status. Of the 124 alcoholics who had attempted suicide, 43 were African American, eight were Hispanic, and 73 were Caucasian, compared with 119, 14, and 76, respectively, among the 209 who had never attempted suicide (n.s.).

Nineteen of the 124 alcoholics who had attempted suicide had a family history of suicide, compared with nine of the 209 alcoholics who had never attempted suicide (χ²=10.88, df=1, p<0.001). Eighteen other alcoholics who had attempted suicide had a first- or second-degree relative who had attempted suicide, compared with 15 other alcoholics who had never attempted suicide (χ²=3.91, df=1, p=0.05).

Discussion

In the present study it was found, as hypothesized, that a family history of suicide was present in significantly more alcohol-dependent patients who had attempted suicide than among alcohol-dependent patients who had not attempted suicide. Among the alcoholics who had attempted suicide, 15.3% had a first- or second-degree relative who had committed suicide, compared to 4.3% among the alcoholics who had never attempted suicide. This result is consistent with findings in studies of other groups of patients. For example, Murphy and Wetzel (2) found that 14% of 127 patients seen after a suicide attempt had a family history of suicide.

Although the most highly significant finding was for a family history of suicide, there was also a significant difference between the alcoholics who had or had not attempted suicide in the history of suicide attempts in a first- or second-degree relative. When a family history of either completed suicide or an attempt at suicide was considered, the rates of a family history of suicidal behavior were 29.8% for the alcoholics who had attempted suicide and 11.5% for the alcoholics who had never attempted suicide. This high percentage is consistent with Murphy and Wetzel’s finding (2) that 34% of suicide attempters with primary affective disorder had a family history of suicide or attempted suicide.

Suicidal behavior is an important problem among alcoholics. Studies show that, as in the present study, up to one-third of alcoholics attempt suicide at some time (3). Another finding of this predominantly male study from a veterans’ hospital was that significantly more of the alcoholics who had attempted suicide were female. However, other studies from diverse clinical settings have also shown a significant excess of women among alcoholics who attempt suicide (3).

Many of the clinical characteristics of alcoholics who attempt suicide have now been described. They include having lower socioeconomic status, being female, beginning heavy drinking at an early age, having antisocial personality disorder, abusing illicit drugs, and having other associated comorbid axis I psychiatric disorders—particularly depression (4–9). The results of the present study suggest that a family history of suicide might also be included among the risk factors for an attempt at suicide among alcoholics. In some instances, such a history may indicate an alcoholic relative who committed suicide (8).

Received Feb. 17, 2000; revision received June 2, 2000; accepted July 17, 2000. From the Psychiatry Service, Department of Veterans Affairs, New Jersey Health Care System. Address reprint requests to Dr. Roy, Psychiatry Service (116A), Department of Veterans Affairs, New Jersey Health Care System, 385 Tremont Ave., East Orange, NJ 07019; [email protected] (e-mail).