Service members with a history of suicide attempt showed significantly greater interoceptive deficits than those with suicidal ideation but no history of attempt. Those with suicidal ideation but no history of attempt showed significantly greater interoceptive deficits than those with no history of either suicidal ideation or attempts. In addition, greater interoceptive deficits were more strongly associated with higher suicidal ideation, more suicide attempts, more non-suicidal self-injuries (NSSI), and greater lethality of suicide attempts than with other risk factors including age, gender, PTSD symptoms, and hopelessness.

Interoceptive deficits are a diminished ability to perceive bodily sensations and are theorized to be necessary for self-injurious thoughts and behaviors to occur. Additionally, research from Dr. April Smith’s lab at Miami University suggests that interoceptive deficits differentiate people who are thinking about suicide from people who engage in suicidal behavior and associate self-injurious thoughts and behaviors overtime. Using the MSRC CDE database, and a variety of analyses, Smith will determine if interoceptive deficits are associated with suicidal and self-injurious thoughts and behaviors, over and above established risk factors for suicide.

To look for this association, questions assessing physiological sensations, pain tolerance, and emotional awareness will be used to create a general measure of interoceptive deficits. The associations with the general measure and suicidal outcomes will then be examined and compared across different groups of participants with varying severity of suicide-related thoughts and behaviors. With this study, Smith has three main objectives. For one, she hopes to determine whether differences in interoceptive deficits differentiate groups consistent with distinct levels of suicide risk.

Her second aim is to test whether having more interoceptive deficits is associated with higher severity of self-injurious thoughts and behaviors. Finally, she looks to test if there are differences in the experience of interoceptive deficits between civilians and military members, and test whether the relationship between interoceptive deficits and self-injurious thoughts and behaviors is different for civilians than for military service members.

Results of Smith’s project provides the potential to improve military suicide risk assessment and identification, as evidence indicates that service members experience proxies of interoceptive deficits (i.e., alexithymia, dissociation, pain tolerance) and that these proxies are associated with suicidality. Furthermore, using these proxies provides a less sensitive way to assess for self-injurious thoughts and behaviors.

For example, asking a service member if they are having difficulty identifying bodily sensations does not carry the same stigma as asking about other self-injurious thoughts and behavior risk factors, and therefore increases the likelihood of disclosure. Accurate identification of high-risk groups may promote intervention delivery to those in need, which may reduce rates of military suicide.