Prevalence of prescription and illicit drugs in suicides by non-poisoning means in the National Violent Death Reporting System 2003-2017

Background Prescription and illicit drugs are important social environmental variables in many suicides regardless of their role as an immediate cause of death. Objectives To investigate the presence of prescription and illicit drugs, either through mention in the death record or toxicology reports, among suicides attributed to nonpoisonous causes to identify patterns of risk. Methods Using the 2003-2017 National Violent Death Reporting System (NVDRS), we examined the presence of prescription and illicit drugs among 143,175 suicides (119,563 males 23,612 females) due to firearms and suffocation/hanging. The presence of drugs (opioids, stimulants, benzodiazepines, muscle relaxants, and cannabis) was determined from toxicology reports and text searches of coroner/medical examiner and law enforcement summaries. We fit multivariable logistic regression models to estimate associations between drug class and suicide method adjusting for decedent characteristics. Results Overall prescription and illicit drugs were present in 22% of firearm deaths and 28% of suffocation deaths. Among victims with toxicology reports, over 20% tested positive for benzodiazepines. Benzodiazepines were mentioned in 4% of firearm and 5% of suffocation suicides without toxicology testing. Stimulants were more likely to occur in suffocation than firearm deaths among victims with toxicology testing (aOR = 1.44, 95% CI: 1.33-1.56) and without toxicology testing (aOR = 1.61, 95% CI: 1.31-1.98). Conclusions Benzodiazepines were most frequently identified in both toxicology reports and narratives of suicides by firearms or suffocation. Better distinction of the presence of prescription and illicit drugs in the environment versus apparent ingestion among non-poisoning suicides are needed to inform prevention approaches.