Commonly Used Depression Questionnaire Can
ARLINGTON, Va. (Dec. 2, 2013) Patients who reported frequent thoughts of death or self-harm as part of a standard questionnaire used in depression treatment were at increased risk of subsequent suicide attempt and suicide death. Researchers found that a response to a single question on the Patient Health Questionnaire (PHQ-9) predicted increased risk of a later suicide attempt or death over a period of several months. The research is presented in the December issue of Psychiatric Services, a journal of the American Psychiatric Association.
Suicide accounts for some 38,000 deaths each year and there are some 600,000 non-fatal suicide attempts each year resulting in emergency department visits. Because there is no evidence to date that any screening test accurately identifies people in the general population who are at risk of suicide, the U.S. Preventive Services Task Force and others do not recommend such screening.
A research team from Seattle’s Group Health Cooperative (GHC), a large integrated health system, conducted the study. Since 2006, all GHC primary care and mental health providers have been advised to administer the PHQ-9 at every visit for depression treatment and clinicians frequently encounter patients who report suicidal ideation on these routinely administered questionnaires. Item 9 of the PHQ-9 asks “Over the last two weeks, how often have you been bothered by thoughts that you would be better off dead, or of hurting yourself in some way?” Response options include, “not at all,” “several days,” “more than half the days,” or “nearly every day.” While the PHQ-9 was designed to measure depression severity not identify risk of suicidal behavior, the researchers were seeking to “provide practical guidance regarding a measure that is widely and increasingly used in everyday practice.”
The research team used electronic medical records, insurance claims, and death certificate data to document what happened to more than 84,000 outpatients age 13 and older who completed the PHQ-9 at every visit for depression between 2007 and 2011. They found that the cumulative risk of suicide attempt over one year was 0.4% among outpatients reporting thoughts of death or self-harm “not at all” compared to 4% among those reporting thoughts of death or self-harm “nearly every day.”
After adjustment for age, sex, treatment history, and overall depression severity, responses to item 9 of the PHQ-9 remained a strong predictor of suicide attempt and a moderate predictor of subsequent suicide death. Even though the age and sex patterns were very different for suicide attempts and deaths, response to PHQ item 9 predicted both.
The authors, led by Gregory E. Simon, MD, MPH, note that the immediate risk of suicide attempt was low but increased over several days and continued to grow for several months, indicating a need for sustained and organized follow-up care to address ongoing risk. “Suicidal ideation should be viewed as an enduring vulnerability rather than simply a short-term crisis,” the authors concluded.