Project Abstract
Few NIMH-funded studies have examined contributors to short-term, within-person changes in suicidal ideation
and odds of suicidal behavior. We propose to use multi-modal assessments (self-report, behavior, actigraphy)
to capture changes in several RDoC domains relevant to suicide risk. In an ideation-to-action framework, we
differentiate acute risk factors for suicidal thoughts from those that contribute to the transition from suicidal
ideation to behavior. We will test our theoretical model using a 28-day intensive longitudinal design in a sample
of suicidal adults leaving inpatient behavioral health care, a population at particularly high risk for suicide.
Aim 1: Examine a set of transtheoretical risk factors as proximal predictors of within-person changes in suicidal
thoughts. Using ecological momentary assessment, we will gather repeated measures of seven hypothesized
ideation risk factors, as well as a dimensional measure of ideation, to model lagged relationships between
affective risk factors and subsequent ideation. We expect that each affective risk factor will show a positive
association with subsequent increases in suicidal ideation, and that these risk factors will co-occur in daily life
such that they are best conceptualized as a single latent construct capturing emotional suffering (psychache).
Aim 2: Test self-report and behavioral measures of inhibitory control as risk factors for suicidal behavior. We
expect that participants who, at baseline, report greater emotion-related impulsivity, and who show impaired
response inhibition in a behavioral task using negative valence stimuli, will have higher odds of suicide attempt
over follow-up. Using a novel mobile adaptation of an inhibitory control task during the ecological momentary
assessment period, we expect that within-person decrements in inhibitory control will precede within-person
increases in likelihood of suicide attempt among individuals thinking of suicide.
Aim 3: Evaluate objectively measured sleep duration as a proximal risk factor for both suicidal ideation and
suicidal behavior. Using wrist-worn actigraphy devices, we will examine how short sleep duration, compared to
participants’ average sleep, relates to next-day ideation and attempts. We expect that short sleep duration will
predict within-person increases in suicidal thoughts, as well as increased likelihood of suicide attempts,
controlling for suicidal ideation. Finally, we will test an exploratory hypothesis, that the sleep-suicide attempt
association is explained by sleep-related decreases in inhibitory control in the context of negative affect.
Findings from this study will elucidate modifiable affective, cognitive, and physiological targets for just-in-time,
mobile interventions to prevent suicide.
