Suicide risk factors after depression vary by sex

NEW YORK (Reuters Health) - Factors that predict suicidal behavior after major depression differ between men and women, according to study findings published in the American Journal of Psychiatry.

"Sex differences in suicidal behavior have long been recognized," Dr. Maria A. Oquendo, of Columbia University, New York, and colleagues write. "Studies have shown that men have higher suicide rates, while women are at higher risk for suicide attempts," they note.

The researchers examined if there were differences between men and women in the risk factors associated with suicidal behavior in a study involving 184 women and 130 men seeking treatment for a major depressive episode. The patients were diagnosed with major depression or bipolar disorder, and were evaluated at 3 months, 1 year and 2 years after discharge.

The team hypothesized that aggression, hostility, and history of substance misuse would increase the risk of suicidal behavior among the men, while depressive symptoms, childhood history of abuse, fewer perceived reasons for living, and borderline personality disorder would increase the risk among the women.

Overall, 4 patients committed suicide and 48 attempted suicide during the follow-up period. This represented 16.6 percent of the study group. Women were almost twice as likely as men to attempt suicide during follow-up.

For men, a previous suicide attempt, family history of suicidal acts, past drug use, cigarette smoking, borderline personality disorder and early parental separation increased the risk of a future suicidal act by at least threefold.

For women, the risk of a future suicide attempt was six times greater among those who had made a previous attempt. Each prior attempt increased the future risk by threefold. The risk of future suicidal acts for women was also increased by suicidal thoughts, lethality of past attempts, hostility, subjective depressive symptoms, fewer perceived reasons for living, an additional diagnosis of borderline personality disorder and cigarette smoking.

Further analysis of the significant predictors among the men revealed cigarette smoking and family history of suicidal acts as the most robust predictors of future suicidal acts. However, "early separation from family, borderline personality disorder, and past drug abuse were no longer predictive," Oquendo's group reports.

Additional analysis of the women's significant predictors revealed that previous attempts, suicidal thoughts, and smoking were independently associated with suicide risk, they note. Factors that were no longer significant included multiple suicide attempts, borderline personality disorder, greater subjective depression, fewer perceived reasons for living, and hostility.

The researchers conclude that this information may improve the evaluation of suicide risk in depressed patients "and guide future research on suicide assessment and prevention."

SOURCE: American Journal of Psychiatry, January 2007.