Risk of Suicidal Self-directed Violence Among US Veteran Survivors of Head and Neck Cancer

This cohort study examines the associations between precancer mental health and pain and postcancer receipt of mental health, substance use disorder, or palliative care services with risk of suicidal self-directed violence. Question Among survivors of head and neck cancer (HNC), which precancer characteristics and postcancer health services are associated with suicidal self-directed violence (SSDV) after cancer diagnosis? Findings Among 7803 US veteran survivors of HNC, precancer chronic pain or mood disorders and postcancer mental health and substance use disorder treatment were associated with increased risk of SSDV. Use of postcancer palliative care was associated with decreased risk of SSDV. Meaning Additional suicide prevention efforts should be directed toward survivors of HNC with precancer and postcancer risk factors for SSDV; palliative care may be an important component of supportive cancer care. IMPORTANCE Head and neck cancer (HNC) survivors are about twice as likely to die by suicide compared with other cancer survivors. OBJECTIVE To examine the associations between precancer mental health and pain and postcancer receipt of mental health, substance use disorder (SUD), or palliative care services with risk of suicidal self-directed violence (SSDV). DESIGN, SETTING, AND PARTICIPANTS This retrospective cohort study used the Veterans Health Administration data of 7803 veterans with a diagnosis of HNC (stage I-IVB) who received cancer treatment between January 1, 2012, and January 1, 2018. Data were analyzed between May 2020 and July 2021. EXPOSURES Presence of precancer chronic pain and SUD diagnoses, and postcancer SUD, mental health, or palliative care treatment. Exposures were defined using International Classification of Diseases, Ninth Revision and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes in Veterans Health Administration administrative data. MAIN OUTCOMES AND MEASURES Dcumented SSDV event, including suicide attempt or death by suicide, after HNC diagnosis. RESULTS Among the cohort of 7803 veterans (7685 [98.4%] male; mean [SD] age, 65 [10.7] years), 72 (0.9%) had at least 1 documented SSDV event following their cancer diagnosis, and 51 (0.7%) died by suicide. Four adjusted modified Poisson regression analyses identified that precancer chronic pain (incidence rate ratio [IRR], 2.58; 95% CI 1.54-4.32) or mood disorder diagnoses (IRR, 1.95; 95% CI, 1.17-3.24) were associated with higher risk of postcancer SSDV. Those who had at least 1 documented mental health (IRR, 2.73; 95% CI, 1.24-6.03) or SUD (IRR, 3.92; 95% CI, 2.46-6.24) treatment encounter in the 90 days following HNC diagnosis were at higher risk for SSDV. A palliative care encounter within 90 days of postcancer diagnosis was associated with decreased risk of SSVD (IRR, 0.49; 95% CI, 0.31-0.78). CONCLUSIONS AND RELEVANCE In this cohort study, a high proportion of HNC survivors with an SSVD event died from their injuries. Identification of risk factors for SSDV among HNC survivors may help direct additional resources to those who are at high risk. Referral to palliative care appears to be an important component of supportive oncologic care to reduce the risk of SSDV.