Abstract / Summary
Abstract Attention deficit hyperactivity disorder (ADHD) is associated with increased premature mortality, particularly from unnatural causes. As the use of stimulant medications has increased globally, more information is needed regarding their occurrence in medico-legally investigated deaths and their relationship with substance use and mortality. This retrospective observational study examined all medico-legal post-mortem (PM) cases in Finland between 2016 and 2024 in which methylphenidate or amphetamine was detected during forensic toxicological investigations. A total of 271 methylphenidate-positive and 1,829 amphetamine-positive cases were identified. The annual number of methylphenidate-positive cases increased throughout the study period, paralleling increasing prescription rates, whereas fatal methylphenidate poisonings remained uncommon (2.6% of all cases positive for methylphenidate). Amphetamine-positive cases and fatal amphetamine poisonings increased until 2020 and subsequently stabilized; fatal amphetamine poisonings accounted for 19% of amphetamine-positive cases. Evidence of non-alcohol substance use was common, occurring in 76% of methylphenidate-positive cases and 97% of amphetamine-positive cases with documented ADHD medication use or diagnosis. Alcohol was detected in approximately one quarter of cases across all groups. Accidental deaths predominated, accounting for 46% of methylphenidate-positive and 49% of amphetamine-positive cases, while suicides accounted for 24% and 19% of deaths, respectively. These findings indicate that PM detections of ADHD medications are strongly associated with substance-use comorbidity and premature unnatural mortality. Although methylphenidate findings increased substantially over time, fatal methylphenidate poisonings remained rare. The deceased individuals represented a particularly high-risk subgroup, highlighting the importance of substance-use and suicide prevention efforts among people with ADHD.