Stimulant use in suicides: A systematic review

Suicide remains a global public health concern and the increased supply and use of synthetic stimulants globally may have implications for the burden of suicides attributable to substance use. This systematic review investigated any potential associations of stimulant use detected in post-mortem biological specimens and suicides. We conducted a systematic review and narrative synthesis (CRD42021237966). Medline, EMBASE, TOXLINE, and Scopus databases were searched for terms related to forensic toxicology, post-mortem toxicology, suicide and stimulants. The primary outcome was to estimate the prevalence of stimulant use in suicides. There were 26 studies whichcontributed to prevalence measures; in studies reporting at the individual compound level, suicides involved cocaine (0.1–23%), caffeine (3.2–22%), 3,4-methylenedioxymethamphetamine (0.1–17%), amphetamine (0.2–9.3%), methamphetamine (3.1–7%), and phentermine (0.9–1%). Overall, stimulant use in suicides was over-represented compared to estimates of stimulant use in the general population and has increased over time. Thirteen case reports used to contextualise suicides involving stimulants found no examples of cocaine or methamphetamine mono-intoxication of suicidal intent. This suggests mechanisms other than acute toxicity involved in stimulant-associated suicide. Future research by in-depth psychological autopsies of suicides involving stimulants, in combination with segmental hair analysis to determine the chronicity of stimulant exposure, may contribute to a better understanding of the burden of suicide attributable to stimulant use.