PROJECT SUMMARY / ABSTRACT
Over the past two decades, suicide rates have increased nearly 35% in the U.S., with up-
ward trends in nearly all demographic groups. Further increases have occurred since the
COVID-19 pandemic began. Despite ambitious goals for reducing suicides and significant fed-
eral and private investment, suicide rates continue to rise unabated. To date, the predominant
approach to mitigating suicide risk in the U.S. is secondary prevention. Typically, these pro-
grams identify risk of recurrence among those who have already attempted suicide at least
once. Although secondary prevention is crucial, the majority of deaths by suicide occur on first
attempt. Thus, targeted primary prevention earlier in development is essential. Most current pri-
mary prevention programs are intensive, expensive, and delivered by highly trained mental
health providers, who are in short supply. Traditional face-to-face therapy is also unavailable to
many who live in underserved communities, and disliked by adolescents, who much prefer digi-
tal delivery on their devices. This high-risk, high-reward proposal addresses these limitations
and needs. We use an experimental therapeutics approach to evaluate the independent and
combined efficacies of two unconventional but scalable interventions: transcutaneous vagus
nerve stimulation (tVNS) to target emotion dysregulation, and a peer-support smartphone app to
combat social isolation. These low-cost interventions, which hold strong promise but have not
been used before, can reach large numbers of adolescents, with much potential to reduce pro-
spective suicide risk. We will enroll 212 adolescents, ages 13-17 years, who show elevations on
at least two prominent risk factors for suicide (e.g., self-injury, maltreatment). Using a 2 × 2 de-
sign, adolescents will be assigned randomly to receive 30 days of treatment with (1) tVNS to tar-
get emotion dysregulation, (2) a peer-support phone app to target social isolation, (3) tVNS + a
peer-support phone app, or (4) enhanced treatment as usual with monitoring and access to re-
sources. Intervention effects on mechanisms (emotion dysregulation, social isolation) proximal
efficacy signals (e.g., physiological reactivity, self-harm) and target outcomes (suicidal ideation,
suicidal behaviors) will be evaluated immediately post-intervention and at one-year follow-up.
Treatment data will be monitored daily to fine-tune dosing of both interventions. This transforma-
tive and innovative proposal tests two novel, scalable preventive interventions designed to
“meet adolescents where they are" by using digital technologies to address core mechanisms of
suicide risk.
