Posthospitalization algorithm may predict suicide risk in soldiers

Among U.S. Army soldiers previously hospitalized for a psychiatric disorder, more than half of posthospitalization suicides occurred in cases predicted to have the highest suicide risk, according to recent findings.

Researchers evaluated the utility of an actuarial posthospitalization suicide algorithm using administrative data. The algorithm was designed to predict suicide in the 12 months after a soldier’s hospitalization for a psychiatric condition, in order to identify those in need of additional posthospitalization care. They evaluated 53,769 hospitalizations of active duty soldiers with psychiatric admission diagnoses from January 2004 through December 2009.

Data showed that 68 soldiers died by suicide within 12 months of hospital discharge. This represents 12% of all U.S. Army suicides, and is equivalent to 263.9 suicides per 100,000 person-years vs. 18.5 Army suicides per 100,000 person-years. The most significant predictors of suicide were: male sex (OR=7.9; 95% CI, 1.9-32.6), weapons possession (OR=5.6; 95% CI, 1.7-18.3), prior suicidal tendencies (OR=2.9; 95% CI, 1.7-4.9), disorders identified and diagnosed during hospital stay such as nonaffective psychosis (OR=2.9; 95% CI, 1.2-7), and late age of enlistment (OR=1.9; 95% CI, 1-3.5).

Notably, 52.9% of the posthospitalization suicides occurred after the 5% of hospitalizations stratified as being at highest risk (3,824.1 suicides per 100,000 person-years). Those in this stratum also had seven deaths from unintentional injury, 830 suicide attempts and 3,765 rehospitalizations within 12 months of hospital discharge.

Researchers wrote that the suicide rate among soldiers now exceeds that of the civilian population, making the identification of high-risk soldiers an important priority.

“Although interventions in this high-risk stratum would not solve the entire U.S. Army suicide problem given that posthospitalization suicides account for only 12% of all U.S. Army suicides, the algorithm would presumably help target preventive intervention,” the researchers said.

“The high concentration of risk of suicides and other adverse outcomes might justify targeting expanded posthospitalization interventions to soldiers classified as having highest post-hospitalization suicide risk, although final determination requires careful consideration of intervention costs, comparative effectiveness and possible adverse effects,” the researchers wrote.

Disclosure: See the study for a full list of relevant financial disclosures.