National trends of suicidal ideation and mental health services use among US adults with opioid use disorder, 2009–2020

BACKGROUND: The substantial increase in deaths by overdose and potential underlying suicidal intent in such deaths suggest the importance of understanding trends of suicidal ideation in individuals with opioid use disorder (OUD). This study aimed to examine the trends and correlates of past-year suicidal ideation (SI) and mental health service use among US adults with past-year OUD from 2009 to 2020. METHODS: We used data from the National Survey on Drug Use and Health. Participants included non-institutionalized US civilians aged ≥18 with past-year OUD (n=5386). SI was measured by self-reported thoughts of killing oneself. Mental health service utilization was assessed with questions concerning receipt of any past-year outpatient or inpatient mental health services or prescription medications. We examined the prevalence and correlates of SI and adjusted odds ratios (aORs) for changes over time adjusting for potentially confounding sociodemographic and clinical characteristics. Further, trends in utilization of mental health services were explored. FINDINGS: From 2009 to 2020, the prevalence of SI increased from 22.8% to 29.8% (average annual percent change, 3.64% [95% CI, 1.01–2.10%]) in adults with OUD. Subgroups including individuals aged 18–25 (aOR, 1.72 [95% CI, 1.09–2.71]; P=0.020), residing in non-metropolitan areas (aOR, 1.43 [95% CI, 1.04–1.97]; P = 0.029), with co-occurring past-year major depressive episode (aOR, 5.28 [95% CI, 4.27–6.53]; P < 0.001) and alcohol (aOR, 1.55 [95% CI, 1.23–1.97]; P < 0.001), cocaine (aOR, 1.42 [95% CI, 1.03–1.97]; P = 0.034), and sedative use disorders (aOR, 1.48 [95% CI, 1.11–1.98]; P = 0.008) were associated with SI after adjusting for covariates. No significant change in mental health service use was observed. Individuals with SI were 2.5 times more likely to report an unmet need for treatment compared to individuals without SI (53.6% vs 21.4%; P < 0.001). INTERPRETATION: The prevalence of SI in adults with OUD increased substantially without a corresponding change in mental health service use. These results underscore the potential benefit of routine screening for suicidality and improved access to care for individuals with OUD, especially those with co-occurring depression and/or polysubstance use. FUNDING: None reported.