A pre-existing anxiety disorder significantly increases the risk of subsequent onset of suicidal thoughts and suicide attempts, according to an article in the November issue of Archives of General Psychiatry.

Suicidal thoughts and suicide attempts are strong risk factors for completed suicides, according to background information in the article. Mood disorders such as depression, substance abuse disorders, and schizophrenia are well-established risk factors for suicidal thoughts and suicide attempts but, the authors suggest, because anxiety disorders often co-exist with these mental disorders, the impact of anxiety disorders on risk for suicidal thoughts and suicide attempts has been difficult to assess.

Jitender Sareen, M.D., F.R.C.P.C., of the University of Manitoba, Winnipeg, and colleagues analyzed data from interviews of a random sampling of people from the Netherlands to determine whether anxiety disorders are risk factors for subsequent suicidal thoughts or attempts. In two follow-up assessments, one year and three years following the baseline interview, the researchers examined whether anxiety disorders at baseline were associated with incidence of suicidal thoughts or suicide attempts.

At the first (one-year) and second (three-year) follow-up periods, there were 41 and 44 new cases of suicidal ideation, respectively (total of 85 new cases at either assessment), and 24 and 15 new cases of suicide attempts, respectively (total of 39 new cases).

After adjusting for other mental disorders and other social factors, the researchers found that the presence of anxiety disorder more than doubled the risk of suicidal thoughts or attempts for the 7,076 participants in the baseline interview.

For the 4,796 people who participated in all three interviews, the presence of anxiety disorders at baseline more than doubled the risk of subsequent suicidal thoughts and more than tripled the risk of subsequent suicide attempts. “Further analysis demonstrated that the presence of any anxiety disorder in combination with a mood disorder was associated with a higher likelihood of suicide attempts in comparison with a mood disorder alone,” the authors reported.

“This is the first study to demonstrate that a pre-existing anxiety disorder is an independent risk factor for subsequent onset of suicidal ideation [thoughts] and attempts,” the authors concluded. “Moreover, the data clearly demonstrate that co-morbid anxiety disorders amplify the risk of suicide attempts in persons with mood disorders. Clinicians and policymakers need to be aware of these findings, and further research is required to delineate whether treatment of anxiety disorders reduces the risk of subsequent suicidal behavior.”