Restricting suicidal patients' access to drugs with high case fatality rates vital to suicide prevention
Patients at risk for suicide should be prevented from accessing drugs with high case fatality rates, according to results of a cross-sectional study published in JAMA Network Open.
Researchers suggested achieving this end by blister packing and securely storing lethal drugs.
“A few studies on suicide prevention by means focused on restricting access to specific, easily accessible toxins, such as pesticides, barbiturates, paracetamol (acetaminophen) or antidepressants,” Ted R. Miller, PhD, principal research scientist at Pacific Institute for Research and Evaluation in Maryland, and colleagues wrote. “Evaluations found that restricting access to these lethal means through prescription practices and sales regulation was associated with declining suicide rates. Thus, drug suicide prevention efforts will benefit from a systematic investigation of suicide lethality by drug class that assesses the separate and interactive risks of varied drugs.”
Previous lethality analyses of suicide means typically treated drug poisoning as a lumped category, except for alcohol. Risk assessment by drug class allows for improved assessment of prevention opportunities, Miller and colleagues noted.
To investigate the epidemiology of drug poisoning suicides, the investigators analyzed censuses of live ED and inpatient discharges for 11 U.S. states from 2011 through 2012. They also analyzed national live discharge samples from the Healthcare Cost and Utilization Project for the same time frame, and for 2016, as well as corresponding Multiple Cause of Death census data. Using diagnosis and external cause codes, they identified censuses or national samples of all medically identified drug poisonings that were deliberately self-inflicted or of undetermined intent.
Distribution of drug classes involved in suicidal overdoses served as the main outcome. The researchers calculated the odds and relative risk of death for a suicide act that involved a drug class vs. similar acts excluding that class using logistic regressions on the state data.
Results showed 421,466 poisoning suicidal acts that resulted in 21,594 deaths. Of the suicidal drug overdoses, 19.6% to 22.5% involved benzodiazepines and 15.4% to 17.3% involved opioids. The researchers identified opioids in 33.3% to 47.8% of fatal suicide poisonings, making them the most identified drug class. Opioids presented the greatest relative risk for poisoning suicide completion, with 5.2 times (95% CI, 4.86-5.57) the mean for suicide acts that did not involve opioids, followed by barbiturates (RR = 4.29; 95% CI, 3.35-5.45), antidepressants (RR = 3.22; 95% CI, 2.95-3.52), antidiabetics (RR = 2.57; 95% CI, 1.94-3.41) and alcohol (RR = 2.04; 95% CI, 1.84-2.26), which the researchers noted was a conservative estimate because 30% of death certifiers do not test for alcohol. Calcium channel blockers also had a high relative risk of 2.24 (95% CI, 1.89-2.61) according to the updated toxin diagnosis coding in in the ICD-10 used to code the 2016 data. Approximately 81% of suicides involving opioids would not have been fatal absent opioids, when translated to attributable fractions. Moreover, 34% of alcohol-involved suicide deaths were attributable to alcohol.
“The suicide prevention concept of ‘means matter’ extends to drug class within poisoning suicides,” the researchers wrote. “This study appears to reemphasize the need to control access to drug classes that increase the risk [for] dying of a suicidal overdose. This study suggests that lethal drug access is particularly an issue for youths because they rarely take a targeted set of drugs, seemingly opting for whatever is accessible.”In a related editorial, Catherine Barber, MPA, senior researcher at Harvard Injury Control Research Center, provided an optimistic lens for the findings of the current study.
“The good news is that most people who become suicidal do not attempt, most people who attempt do not die, and, 90% or more of those who attempt and survive — even very serious attempts — do not later take their lives,” Barber wrote. “Becoming suicidal is not a death sentence. In their roles as prescribers, healers and advisors, physicians can help to reduce both the likelihood of an attempt and, with the help of research like that by Miller et al, the risk that an attempt will prove fatal.” – by Joe Gramigna
Disclosures: Miller reports grants from the Health Resources and Services Administration of the Department of Health and Human Services and the National Institute of Mental Health (NIMH); an independent evaluation contract from the AB InBev Foundation, which has links to the alcohol industry; and funding for plaintiff litigation support in lawsuits filed by state and local governments against the opioid industry. Please see the study for all other authors’ relevant financial disclosures. Barber reports personal fees from Appalachian State University, Education Development Center and Intermountain Healthcare.