The Overlooked Crisis: Drug Self-Intoxication Mortality Increased at 5 Times the Rate of Suicide Mortality During the US Opioid Epidemic (1999-2023).

OBJECTIVE

To examine demographic and regional variations in self-injury mortality (SIM) among individuals aged 15 years or older in the United States with mental and behavioral disorders as contributing causes of death from 1999 to 2023.

METHODS

Death certificates from the CDC-WONDER (Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research) database were examined from January 1, 1999, through December 31, 2023, to identify SIM (suicides and drug self-intoxication-related deaths) among individuals with mental and behavioral disorders. Age-adjusted mortality rates (AAMRs) per 100,000 persons were calculated, and temporal trends were described by calculating annual percent change and average annual percentage change (AAPC) using joinpoint regression analysis.

RESULTS

From 1999 to 2023, a total of 639,462 SIM-related deaths were recorded among individuals with mental and behavioral disorders in the United States. The AAMR increased from 2.22 in 1999 to 24.75 in 2023 with an AAPC of 10.17% (95% CI, 9.57% to 11.27%; P<.001). Drug self-intoxication mortality (AAPC, 11.85%) increased at over 5 times the rate of suicide mortality (AAPC, 2.25%) during this period. Around 90% of these deaths were recorded among individuals with substance use disorders. Men had higher mortality rates than women, with AAMRs increasing from 3.50 in 1999 to 35.74 in 2023 among males and from 1.01 to 13.69 in females over the study period. Non-Hispanic Black individuals had the highest AAMR, which increased from 2.70 in 1999 to 41.58 in 2023, followed by non-Hispanic White persons and Hispanic or Latino groups. The Northeast region had the highest SIM-related mortality (32.15 in 2023), and urban areas had higher AAMR than rural areas (21.22 vs 18.51 in 2020).

CONCLUSION

Self-injury mortality among individuals with mental and behavioral disorders-especially those with substance use disorders-has steadily increased from 1999 to 2023. This rise has been driven primarily by a sharp increase in drug self-intoxication mortality, which has grown at over 5 times the rate of suicide mortality, alongside substantial demographic disparities.