An analysis of survey data from more than 280,000 young adults ages 18-35 showed that cannabis (marijuana) use was associated with increased risks of thoughts of suicide (suicidal ideation), suicide plan, and suicide attempt.
These associations remained regardless of whether someone was also experiencing depression, and the risks were greater for women than for men.
The study published online today in JAMA Network Open and was conducted by researchers at the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health.
“While we cannot establish that cannabis use caused the increased suicidality we observed in this study, these associations warrant further research, especially given the great burden of suicide on young adults,” said NIDA Director Nora Volkow, M.D., senior author of this study.
“As we better understand the relationship between cannabis use, depression, and suicidality, clinicians will be able to provide better guidance and care to patients.”
The number of adults in the United States who use cannabis more than doubled from 22.6 million in 2008 to 45.0 million in 2019, and the number of daily or near-daily users almost tripled from 3.6 million to 9.8 million in 2019. Over the same time span, the number of adults with depression also increased, as did the number of people who reported suicidal ideation or plan or who died by suicide. To date, however, the relationship between trends in cannabis use and suicidality is not well understood.
The current study sought to fill this gap. For their analysis, NIDA researchers examined data from the 2008-2019 National Surveys on Drug Use and Health (NSDUH). NSDUH, which is conducted annually by the Substance Abuse and Mental Health Services Administration, collects nationally representative data among the U.S. civilian, noninstitutionalized population age 12 or older on cannabis use and use disorder, depression, suicidality, and other behavioral health indicators.
In addition to determining the associations between these factors, the researchers examined whether the associations varied by gender. They examined data from 281,650 young adults ages 18 to 35 years – the age range when most substance use and mood disorders emerge – with an almost even number of women and men.
The researchers compared four levels of past-year cannabis use: no cannabis use; nondaily cannabis use; daily cannabis use, which was defined as use on at least 300 days per year; and presence of cannabis use disorder, which was assessed in the survey and involves meeting specific criteria for a pattern of continued cannabis use despite negative consequences.
To determine the presence of depression, they assessed the prevalence of major depressive episodes based on specific diagnostic criteria measured through the survey. To identify suicidality trends, the investigators separately assessed the trends in the prevalence of past-year suicidal ideation, plan, and attempt as reported in the 2008-2019 NSDUH surveys.
The results of the study indicated that even people who used cannabis nondaily, fewer than 300 days a year, were more likely to have suicidal ideation and to plan or attempt suicide than those who did not use the drug at all. These associations remained regardless of whether someone was also experiencing depression.
Among people without a major depressive episode, about 3% of those who did not use cannabis had suicidal ideation, compared with about 7% of those with nondaily cannabis use, about 9% of those with daily cannabis use, and 14% of those with a cannabis use disorder.
Among people with depression, 35% of people who did not use cannabis had suicidal ideation, compared to 44% of those with nondaily cannabis use, 53% of those who used cannabis daily, and 50% of those who had a cannabis use disorder. Similar trends existed for the associations between different levels of cannabis use and suicide plan or attempt.
Moreover, the researchers found that women who used cannabis at any level were more likely to have suicidal ideation or report a suicide plan or attempt than men with the same levels of cannabis use. For example, among individuals without major depressive episode, the prevalence of suicidal ideation for those with vs. without a cannabis use disorder was 13.9% vs. 3.5% among women and 9.9% vs. 3.0% among men.
Among individuals with both cannabis use disorder and major depressive episode, the prevalence of past-year suicide plan was 52% higher for women (23.7%) than men (15.6%).
“Suicide is a leading cause of death among young adults in the United States, and the findings of this study offer important information that may help us reduce this risk,” explained lead author Beth Han, M.D., Ph.D., M.P.H., from NIDA. “Depression and cannabis use disorder are treatable conditions, and cannabis use can be modified.
Through better understanding the associations of different risk factors for suicidality, we hope to offer new targets for prevention and intervention in individuals that we know may be at high-risk. These findings also underscore the importance of tailoring interventions in a way that take sex and gender into account.”
Epidemiological evidence indicates that the extent of substance abuse is not limited to patients with psychiatric disorders or substance use disorders (SUDs). On the contrary, the phenomenon mostly involves a heterogeneous cohort of users that includes “psychonauts,” clubgoers, students, marginalized or non-habitual recreational drugs consumers [1].
More- over, recent studies show that the likelihood of approaching legal and illegal psychoactive substances occurs at an increasingly younger age. Substances are cheap and readily avail- able online, thereby becoming accessible even to children, a phenomenon loaded with dramatic consequences in terms of mortality and psychiatric outcomes [2,3].
According to data from the U.S. study Adolescent Brain Cognitive Development (ABCD), after alcohol, cannabis is the second most used substance of abuse by adolescents with a prevalence rate of 35.6% [4]. A wide range of other substances is also available, including the so-called Novel Psychoactive Substances (NPS), like synthetic cannabinoids and synthetic cathinones, dissociatives, opioids, stimulants, gamma-hydroxybutyrate, and other “club drugs” [5].
In today’s globalized and fast-paced world, adolescents and young adults are con- strained to an inner world dominated by “instantaneity.” Missing, among the youngsters, is the ability to ponder the medium and long-term effects of individual behaviors and life-choices as well the capability to project and envision themselves in stable social roles.
The search for individualization, self-identity, intimacy, and future orientation is further complicated by societal pressure [6]. This psychosocial milieu leads users to seek instant gratification in a constant quest for euphoria, alertness, sociability, enhanced sensory per- ceptions, alterations of space and time perception, loss of inhibition, and improved sexual performance [7–9].
This behavior may be particularly at risk for adolescents and young adults who are often unaware of the health risks associated with the use of psychoactive compounds including those linked to the chemical contamination and adulteration by neurotoxic additives [5].
Acute and chronic drug misuse or abuse may impair judgment, weaken impulse control, and interrupt the functioning of critical inhibitory neurotransmitter pathways, thereby leading to enhanced suicidal tendencies driven by disinhibition [10]. Although few studies have addressed the issue of the incidence and predictors of suicide among users, psychoactive drugs play a significant role in suicidality when used for intentional overdose or, more frequently, when the intoxication leads to disinhibition and alterations in judgement that make suicide more likely [11,12].
For instance, a study reported that adolescent users of psychoactive substances are more likely to commit suicide by firearms than adolescents who do not use drugs [13].
Even the occasional use of psychoactive substances may be a significant risk factor for various dangerous conditions, including fatal and nonfatal overdoses, suicide attempts, and death by suicide [14,15].
Evidence indicates that, compared with the general pop- ulation, individuals who use alcohol or drugs have a 10–14 times greater risk of death by suicide [16].
Furthermore, high rates of psychoactive substance use are found in post- mortem examination of body fluids of subjects whose death was classified as suicide or due to accidents [17].
This phenomenon is particularly alarming if one considers the novel, highly potent, and addictive compounds such as synthetic opioids flooding the market.
The dramatic rise in non-medical use of prescription opioids in the U.S. has been reported as an additional risk factor for intentional overdose and suicide [18,19]. In 2015, opioids were identified as the main cause of death in almost one-third of the suicides due to poisonings in the United States [20].
The epidemic is critically important in demographics that become less resilient to the risk of substance abuse due to increased chronic medical comorbidities, neurotoxic damage, and higher neuropsychiatric diseases [21]. Furthermore, as adolescence and young age involve a variety of major emotional, social, and physical changes, these factors are additional risk factors for the development of depressive symp- toms and behavioral problems [17].
In this context, the risk of sudden death or suicide becomes exponential. In addition to this, several factors associated with substance use, such as psychiatric and medical comorbidities, financial difficulties, and unemployment, may also contribute to higher suicide risk [22].
The variety of medical and social consequences associated with substance use requires effective public health policies set to counteract these habits, as well as a continuous education update for health professionals to promote education and harm reduction [23,24].
Ibiza, one of the most popular nightlife hotspots for summer holidays in Europe, represents an important setting to search the psychopathological milieu of the misuse of novel and “vintage” drugs. Previous studies had evidenced a higher prevalence of risky behaviors showed by residents and tourists. These include problematic alcohol and substance use and the related intoxication, fatalities, overdoses, suicide attempts, or suicide [25,26].
Therefore, we conducted an observational study on a cohort of subjects who accessed the psychiatric ward of the Can Misses Hospital in Ibiza as a consequence of intoxication by psychoactive substances.
The main objective of the study was to assess psychopathological and suicidal fea- tures associated with substance use. Suicidality was measured considering three variables: suicidal ideation, suicide attempts, and death ideation according to The Columbia Suicide Severity Rating Scale (C-SSRS).
The study also aimed explicitly to (1) identify the suici- dality prevalence among drugs misusers, (2) evaluate the differences in Suicide Ideation Intensity (SSI; occurring through life and in the month before recruitment) among users of different substances, (3) evaluate the associations of SSI (lifetime and in the last month) with psychopathological features assessed by the Positive and Negative Symptoms Scale (PANSS), Mania Rating Scale (MRS), and Hamilton Depression Scale (HAM-D) scores.
reference link : https://doi.org/10.3390/brainsci11040490
More information: JAMA Network Open (2021). DOI: 10.1001/jamanetworkopen.2021.13025
