RESUMO
OBJECTIVE/BACKGROUND: A clear link between insomnia concerns and suicidal ideation has been shown in a variety of populations. These investigations failed to use a theoretical lens in understanding this relationship. Research within the veteran population has demonstrated that feelings of thwarted belongingness (TB), but not perceived burdensomeness (PB), mediate the insomnia and suicidal ideation relationship. Using two high risk samples, the present investigation replicated and extended this line of inquiry to include interpersonal hopelessness about TB, a key component of the Interpersonal Psychological Theory of Suicide. METHODS/RESULTS/CONCLUSIONS: Using medical record review and survey data, study 1 replicated the finding that TB is a stronger explanatory factor of the insomnia to suicidal ideation/suicide risk relationship in a sample of N = 200 treatment-seeking active-duty personnel. Study 2 found that insomnia symptoms had an indirect effect on suicidal ideation through TB and PB but not interpersonal hopelessness in a sample of N = 151 college students with a history of suicidal thoughts and/or behaviors. TB was the only mediator of the insomnia-suicide attempt likelihood link and insomnia to clinically significant suicide risk screening status. Limitations include cross-sectional design of both studies and the lack of formal diagnoses of insomnia. Implications and future research directions are discussed.