SAN DIEGO – Among patients presenting to the emergency department with suicidal ideation, the number of previous psychiatric admissions is the most important predictor of a subsequent suicide attempt, results from a 2-year-long study showed.
Doug Brunk/MDedge News
Anne C. Knorr
Momentary measures – significant current difficulties with sleep, energy, or appetite, and anhedonia – “are important considerations during suicide risk assessment, regardless of whether the patient meets the threshold for major depressive disorder, lead study author Anne C. Knorr said in an interview in advance of the annual meeting of the American College of Emergency Physicians.
“Many traditionally studied psychiatric risk factors do not significantly differ between individuals who think about suicide and those who act on their suicidal thoughts, an important distinction as only one-third of those who think about suicide carry out a suicide attempt. While there is support for some psychiatric factors – for example, anxiety, substance use disorders, sleep disturbance – being useful in differentiating these groups, the current study is unique in its use of a longitudinal design to identify influential risk factors that predict future suicide attempt among those with suicidal ideation,” she said.
Ms. Knorr, a research project manager at Geisinger Medical Center, Danville, Pa., and her colleagues collected electronic medical record data from 908 patients who had received a psychiatric evaluation at an index emergency department visit for suicidal ideation over a 2-year period. The mean age of patients was 39 years. The target sample was 30 patients who had returned to the ED following a suicide attempt within 6 months of their index ED visit.
The researchers analyzed 32 predictor variables from patient charts, including demographics, psychiatric history, and current psychiatric presentation. The evaluation was done with “a machine learning statistical approach which is more capable than traditional statistical approaches in handling a large number of predictor variables,” Ms. Knorr said.
The number of previous psychiatric admissions was the most important predictor of a subsequent suicide attempt. The next nine most important variables were sleep disturbance, history of family suicide, low energy, patient age, psychiatrist determination of severe suicide risk, psychiatrist determination of moderate suicide risk, appetite issues, presence of a support system, and loss of interest/pleasure.
These symptoms may not typically be weighed heavily in risk assessments, Ms. Knorr said. “Additionally, given that research suggests that the clinical determination of suicide risk is historically poor, it was interesting that psychiatrist determination of moderate or high risk was influential in predicting a return visit for suicide attempt. Finally, we were surprised that a past history of suicide attempt, often viewed as the strongest predictor of a future suicide attempt, did not emerge as one of the top 10 influential predictors.
“Limitations of this study include the use of a return visit to a Geisinger emergency department as the only measure of a future suicide attempt and the utilization of data from only one health system,” she noted.
The study was funded by the Geisinger Clinic Research Fund. One of the coauthors, Andrei Nemoianu, MD, reported receipt of a research grant from Takeda Pharmaceuticals for a separate study.
SOURCE: Knorr A et al. Ann Emerg Med. 2018 Oct;72;4:S23. doi. 10.1016/j.annemergmed.2018.08.055.