Warning signs in a period of acute risk for suicide attempt: The utility of count- and combination-based classification.

OBJECTIVE: This study sought to establish if models involving the specific combinations of identifiable behavioral warning signs (WS; i.e., alcohol use, suicidal communications, preparation of personal affairs, experiencing negative interpersonal life events) for a suicide attempt outperformed a simpler count model of WS to distinguish an acute risk period (the six hours prior to a suicide attempt) from a control period (a matched six-hour period the day prior). METHOD: Generalized linear mixed models tested all logical combinations of four behavioral WS in addition to a count variable of the number of behavioral warning signs. For the count variable, receiver operating characteristic curve analysis was utilized to determine the optimal cut point for the number of endorsed WS. RESULTS: Area under the curve (AUC) compared classification across all models, with the count model demonstrating similar classification performance to the best multivariate model (AUCs of 0.72 and 0.73, respectively), with an optimal cut point of endorsing one or more WS. CONCLUSION: Although determinations of acute risk should be informed by multiple sources of information, this study suggests a relatively simple count-based approach that considers the presence of one (or more) behavioral WS may be used as a potential indication of increased acute risk for suicide attempt.

A dose-response meta-analysis on the relationship between average amount of alcohol consumed and death by suicide.

BACKGROUND: To determine whether sub-clinical levels of drinking may contribute to suicide risk, and whether the risk differs by sex, we aimed to evaluate the relationship between average amount of alcohol consumed per day and death by suicide. METHODS: A systematic literature search was performed in Embase, Medline, PsycINFO, PubMed, and Web of Science from database inception up to April 27, 2022. The search strategies incorporated a combination of medical subject headings and keywords for "alcohol use" and "suicide". One-stage dose-response meta-analyses using a restricted maximum likelihood random-effect estimator were conducted to explore the relationship between average alcohol volume consumed and suicide, by sex. Three different shapes of the dose-response relationship-linear (on the log-scale), quadratic, and restrictive cubic splines-were tested. RESULTS: A total of eight studies were included (three studies for females (n=781,205), and eight studies for males (n=1,215,772)). A linear dose-response relationship between average alcohol volume consumed and the log-risk of suicide was identified for both males and females. For males and females, a relative risk (RR) of 1.11 (95% CI: 1.05, 1.18) and 1.64 (95% CI: 1.07, 2.51) for suicide when consuming an average of 10 g of pure alcohol per day compared to lifetime abstention, 1.38 (95% CI: 1.14, 1.66) and 4.39 (95% CI: 1.21, 15.88) for 30g/day, and 1.71 (95% CI: 1.25, 2.33) and 11.75 (95% CI: 1.38, 100.33) for 50g/day, respectively. CONCLUSIONS: As consumption increases, the risk of suicide increases proportionally. The risk of suicide associated with average daily alcohol consumption may be elevated for females, compared with males. Albeit, more research is needed, particularly among females.

The Virtual Hope Box mobile application: A systematic review of the literature.

INTRODUCTION: The Virtual Hope Box (VHB) mobile application is an adapted version of the conventional hope box intervention that is used in several evidence-based treatments for suicide behaviors. The VHB is an award-winning app developed by a collaboration between the Departments of Defense and Veterans Affairs. Multiple studies have assessed the utility and effectiveness of the VHB for use in suicide prevention, but no reviews of the literature have been conducted. METHODS: Authors performed a review of the literature using PsycINFO, EBSCOhost, and PubMed. 15 articles were ultimately included. RESULTS: Results were categorized into three areas: (1) efficacy and effectiveness, (2) feasibility, awareness, and usage in high-risk populations, and (3) implementation approaches to increase use among patients and providers. Existing evidence for the VHB supports its feasibility and acceptability, especially among military and veteran populations. Only one study investigated effectiveness in a randomized control trial. Although the VHB developers have disseminated the app nationally, low adoption rates among veteran patients and VA providers remain. Studies found that educational implementation strategies can improve utilization rates. CONCLUSIONS: Future research should examine suicide behaviors as outcomes, approaches to incorporating the VHB into treatment, and a range of populations.

24-Hour warning signs for adolescent suicide attempts.

BACKGROUND: Little is known about when youth may be at greatest risk for attempting suicide, which is critically important information for the parents, caregivers, and professionals who care for youth at risk. This study used adolescent and parent reports, and a case-crossover, within-subject design to identify 24-hour warning signs (WS) for suicide attempts. METHODS: Adolescents (N = 1094, ages 13 to 18) with one or more suicide risk factors were enrolled and invited to complete bi-weekly, 8-10 item text message surveys for 18 months. Adolescents who reported a suicide attempt (survey item) were invited to participate in an interview regarding their thoughts, feelings/emotions, and behaviors/events during the 24-hours prior to their attempt (case period) and a prior 24-hour period (control period). Their parents participated in an interview regarding the adolescents' behaviors/events during these same periods. Adolescent or adolescent and parent interviews were completed for 105 adolescents (81.9% female; 66.7% White, 19.0% Black, 14.3% other). RESULTS: Both parent and adolescent reports of suicidal communications and withdrawal from social and other activities differentiated case and control periods. Adolescent reports also identified feelings (self-hate, emotional pain, rush of feelings, lower levels of rage toward others), cognitions (suicidal rumination, perceived burdensomeness, anger/hostility), and serious conflict with parents as WS in multi-variable models. CONCLUSIONS: This study identified 24-hour WS in the domains of cognitions, feelings, and behaviors/events, providing an evidence base for the dissemination of information about signs of proximal risk for adolescent suicide attempts.

Multidimensional Evaluation of Screening Brief Intervention and Referral to Treatment Training for Medical Students.

OBJECTIVE: Screening, Brief Intervention, and Referral to Treatment (SBIRT) is an evidence-based approach to identifying and addressing alcohol use in non-specialty settings. Many medical schools teach SBIRT, but most published evaluations of these efforts exclude rigorous skill assessments and teaching methods. METHODS: During the 2017-2018 academic year, 146 third-year medical students received classroom-based learning on SBIRT and motivational interviewing (MI) and at least two SBIRT practices with feedback as part of a 4-week psychiatry clerkship. The objective of this curriculum was to improve SBIRT knowledge, attitudes, and confidence and enable learners to skillfully deliver SBIRT. Outcomes evaluated included satisfaction, knowledge, attitudes and confidence, and clinical skill in delivering SBIRT to a standardized patient (rated by the actor, as well as an expert). RESULTS: Results indicated acceptable satisfaction at post-curriculum and significant improvements in attitudes and knowledge from pre- to post-curriculum. On the clinical skills exam, all students were rated as having mastered at least 80% of SBIRT elements by standardized patients and 91.8% were rated at this level by a faculty expert. Student attitudes and knowledge were unrelated to expert ratings, and standardized patient ratings had limited associations with expert ratings. CONCLUSIONS: These results suggest curriculum objectives were achieved and provide unique contributions to the SBIRT curricular outcome research for healthcare trainees. Other findings included that trainee knowledge and confidence may not relate to skill, and standardized patient feedback provides different information on SBIRT and MI skill than expert ratings.

A controlled examination of acute warning signs for suicide attempts among hospitalized patients.

BACKGROUND: Near-term risk factors for suicidal behavior, referred to as 'warning signs' (WS), distinguish periods of acute heightened risk from periods of lower risk within an individual. No prior published study has examined, using a controlled study design, a broad set of hypothesized WS for suicide attempt. This study addressed this gap through examination of hypothesized behavioral/experiential, cognitive, and affective WS among patients recently hospitalized following a suicide attempt. METHODS: Participants were recruited during hospitalization from five medical centers across the USA including two civilian hospitals and three Veterans Health Administration facilities (n = 349). A within-person case-crossover study design was used, where each patient served as her/his own control. WS were measured by the Timeline Follow-back for Suicide Attempts Interview and were operationalized as factors that were present (v. absent) or that increased in frequency/intensity within an individual during the 6 h preceding the suicide attempt (case period) compared to the corresponding 6 h on the day before (control period). RESULTS: Select WS were associated with near-term risk for suicide attempt including suicide-related communications, preparing personal affairs, drinking alcohol, experiencing a negative interpersonal event, and increases in key affective (e.g. emptiness) and cognitive (e.g. burdensomeness) responses. CONCLUSIONS: The identification of WS for suicidal behavior can enhance risk recognition efforts by medical providers, patients, their families, and other stakeholders that can serve to inform acute risk management decisions.

Motivations for Suicide Attempts amongst Psychiatric Inpatients: Associations with Risk Factors and Recent Suicide Attempt Characteristics.

Suicide is a major and preventable public health issue and research has identified several distal risk factors for determining individuals at risk for a suicide attempt. However, understanding imminent processes could enhance individualized safety plan formulations and interventions. Motivation for suicide attempt (MfSA) reflects why an individual engages in a specific attempt. Research indicates such motives can be organized into major factors, but consensus on the number, and their correlates, has not been reached. The sample consisted of 190 patients who attempted suicide within 24 hours of hospitalization and completed the MfSA within the Suicide Attempt-Self Injury Interview. Exploratory factor and correlational analyses were conducted to identify the factors that underlie MfSA. Regression analyses were conducted to examine the relations of MfSA factors to distal suicide risk factors and suicide-related attempt characteristics. Two underlying MfSA factors were identified. Interpersonal MfSA was associated with lower age and higher problematic alcohol use. Intrapersonal MfSA was related to having previous suicide attempts, more past year negative life events, and higher depressive symptoms. The modified MfSA is easy to administer, and its factors show unique associations with important suicide-related constructs. The results could inform safety planning procedures to prevent future death by suicide.

Acute stressors and clinical characteristics differentiate death by suicide, accident, or natural causes among illicit and prescription opiate users.

BACKGROUND: Opiate misuse has reached epidemic levels. Prevention efforts depend on distinguishing opiate users from abusers. The current study compared opioid users who died by natural cases, accidents, and suicide using psychological autopsy methods. Groups were compared on substance use characteristics, treatment history, experiences of negative life events, and circumstances at the time of death. METHODS: Substance use and suicide risk were evaluated using psychological autopsy methods in 63 decedents with positive toxicology for opiates at death divided into three groups: adults dying by suicide (n = 19), accident (n = 19), and natural causes (n = 25). Groups were compared on several dependent measures, using chi-square analyses to examine categorical variables and one-way analyses of variance (ANOVA) to examine continuous variables. RESULTS: Individuals who died by suicide were similar in many ways to adults who died by an accidental overdose. However, suicide completers were more likely to have struggled with severe depression, and previously attempted suicide, whereas the accidental overdose sample was more likely to display a chronic pattern of severe drug abuse. CONCLUSIONS: The current study helps to distinguish between opiate users who are at risk for death by an accidental or intentional overdose. In the ongoing opiate crisis, clinicians must understand the risk of overdose and the nuances of accidental behaviors compared to purposeful ones. Signs of suicidal planning, relevant psychopathology, and ongoing life stress may be useful points of intervention for stopping the increasing number of deaths among opiate users.

A preliminary examination of the association between drinking as a typical coping strategy and level of acute alcohol consumption prior to a suicide attempt.

Drinking to cope is associated with suicide ideation and attempts. Event-based research shows drinking, particularly when alcohol is consumed in large quantities, increases the intensity of suicidal thoughts and immediate risk for attempt. Such findings suggest those who typically drink to cope may be especially likely to drink heavily in the hours preceding a suicide attempt. In the first examination of the association between regular use of alcohol as a coping strategy and acute alcohol consumption prior to a suicide attempt, participants included 130 patients hospitalized for a recent attempt. The number of drinks consumed in the acute period preceding the attempt, as well as past-year heavy drinking frequency, typical drinking motives, and depressive symptoms were assessed. The unique impacts of coping motives on odds of consuming any alcohol, and of using specific amounts of alcohol in the acute period, were determined through binary and multinomial logistic regressions. Results demonstrated that commonly drinking for coping motives increased the odds of heavy drinking - but not of using alcohol at low levels - during the acute period. Results held after adjusting for relevant covariates. Clinicians should assess drinking motives and prioritize prevention of drinking to cope to reduce risk of alcohol-related suicide attempts.

Suicidal Behavior: Links Between Alcohol Use Disorder and Acute Use of Alcohol.

Research on associations of suicidal behavior, including suicide and suicide attempt, with alcohol use disorder (AUD) and acute use of alcohol (AUA) are discussed, with an emphasis on data from meta-analyses. Based on psychological autopsy investigations, results indicate that AUD is prevalent among individuals who die by suicide. Results also indicate that AUD is a potent risk factor for suicidal behavior. Risk estimates are higher for individuals with AUD in treatment settings, when compared to individuals in the community who have AUD. Also, although rates of suicide and prevalence of AUD remain higher in men, they have increased more among women in recent decades. Based on postmortem blood alcohol concentrations, AUA was commonly present among those who died by suicide. AUA is a potent proximal risk factor for suicidal behavior, and the risk increases with the amount of alcohol consumed, consistent with a dose-response relationship. Research indicates that AUA increases risk for suicidal behavior by lowering inhibition and promoting suicidal thoughts. There is support for policies that serve to reduce alcohol availability in populations with high rates of AUD and suicide, that promote AUD treatment, and that defer suicide risk assessments in intoxicated patients to allow the blood alcohol concentration to decrease.

Commentary: Opioid use disorder and suicide: An important opportunity to address two significant public health epidemics.

Nationwide, the opioid epidemic continues to have a significant and widespread adverse impact on morbidity and mortality. The number of individuals dying by suicide and unintentional overdose has continued to increase over the past decade, with opioids being involved in a significant proportion of each category of mortality in 2017. Currently, most strategies for decreasing opioid-overdose deaths do not include systematic screening for suicide risk, nor do they address the necessity to customize interventions for those who misuse opioids to decrease near-term suicide risk (defined here as less than 72 h) factors. Improved screening of near-term and chronic suicide risk along with rapid access to treatment is of critical importance to prevent opioid-related deaths by suicide.

Impulsivity facets and perceived likelihood of future suicide attempt among patients who recently attempted suicide.

BACKGROUND: Given the substantial heterogeneity of both impulsivity and suicidality, increased specificity in studying relations between these variables is needed. One aspect of suicidality that may be especially important for predicting future risk among those with a recent suicide attempt is self-perceived likelihood of making a future attempt (suicide likelihood). Presently, little is known about the extent to which impulsivity is related to this important aspect of suicidality. We examined whether three distinct impulsivity facets (i.e., deficits in conscientiousness, negative urgency, and sensation seeking) would differentially predict suicide likelihood. METHODS: Participants included 155 psychiatric inpatients who presented to a Level-1 trauma hospital after a recent suicide attempt. Structural Equation Modeling (SEM), in which demographic and clinical covariates were controlled, was conducted to examine whether each impulsivity facet would uniquely predict suicide likelihood. RESULTS: Deficits in conscientiousness was the only robust predictor of suicide likelihood, with an association that persisted after accounting for demographic and clinical covariates. LIMITATIONS: The cross-sectional design and unknown predictive validity of suicide likelihood are study limitations. CONCLUSION: This was a preliminary investigation of impulsivity facets with suicide likelihood. Clinical implications of this study suggest that deficits in conscientiousness and suicide likelihood may be important factors to consider when identifying and intervening with patients at high-risk for suicide.

Number and violence of suicide attempt methods: A preliminary investigation of the associations with fearlessness of suicide and fearlessness about death.

The Interpersonal Psychological Theory of Suicide (IPTS) proposes that to attempt suicide one must not only desire death, but must also have acquired the capability to act on that desire. The IPTS states capability for suicide can be acquired through exposure to painful and provocative events, with events most closely related to suicide (e.g., non-fatal attempt) having the strongest effects on capability. We tested the effects of two aspects of suicide attempt history-number and violence of methods-on acquired capability, operationalized as both fearlessness about death and fearlessness of suicide, in a sample of psychiatric inpatients with a history of multiple suicide attempts. Results from three separate models suggest that number of methods and number of violent methods, but not history of ever using a violent method, are associated with increased fearlessness of suicide, even after accounting for hopelessness, general painful and provocative events, NSSI, and number of attempts. Few variables were associated with fearlessness about death. Our results raise the possibility that fearlessness of death and suicide may not be synonymous constructs. They also indicate that number of methods, and/or number of violent methods, may be important markers of fearlessness of suicide among those at high risk.

Depressive symptoms, alcohol use and coping drinking motives: Examining various pathways to suicide attempts among young men.

BACKGROUND: Research has identified several correlates of suicidal behaviors including depressive symptoms, alcohol use and coping drinking motives. However, their associations and their role as possible causal mechanisms in the prediction of suicide attempt are not well understood. This study examined, both cross-sectionally and longitudinally, the potential pathways from alcohol use, drinking coping motives, and depression to suicide attempts. METHODS: Participants (N = 4617) were young Swiss men (mean age = 19.95) participating in the Cohort Study on Substance Use Risk Factors. Measures of depressive symptoms, alcohol use (total drinks per week, heavy episode drinking) and coping drinking motives were used from the baseline and/or 15-month follow-up assessments to predict follow-up suicide attempt. RESULTS: Main findings showed indirect associations through depressive symptoms, such that coping drinking motives were positively associated with depressive symptoms, which were in turn positively related to suicide attempts over time (for total drinks per week models, cross-sectional model: B = 0.130, SE = 0.035, 95% CI = 0.072, 0.207; longitudinal model: B = 0.039, SE = 0.013, 95% CI = 0.019, 0.069). Alcohol use was not significantly related to suicide attempt. LIMITATIONS: Main limitation includes a low prevalence rate for suicide attempt potentially reducing power effects in the analyses and our focus on distal-yet not proximal, role of alcohol use on suicide attempt. CONCLUSIONS: Findings of this study suggest that young men with depressive symptoms and/or those who use alcohol to cope with negative affect may benefit from programs targeting suicidal behaviors.

Empirical extension of the interpersonal theory of suicide: Investigating the role of interpersonal hopelessness.

The Interpersonal Theory of Suicide posits that hopelessness about thwarted belongingness and perceived burdensomeness is an important risk factor for the desire for suicide and suicide risk. Past research has indicated that general feelings of hopelessness interact with the constructs of thwarted belongingness and perceived burdensomeness to predict suicide ideation. However, no research has explicitly tested whether hopelessness specific to the interpersonal constructs of thwarted belongingness and perceived burdensomeness predicts suicide ideation and suicide risk. Participants in the current study (N = 173) were undergraduate students oversampled for history of suicide ideation, planning for suicide, and suicide attempt(s). Participants completed study measures online, including a new measure of hopelessness about thwarted belongingness and perceived burdensomeness. Results indicated that a three-way interaction of thwarted belongingness, perceived burdensomeness, and hopelessness about these interpersonal constructs, but not general hopelessness, predicted unique variance of suicide ideation and suicide risk. Results suggest that hopelessness about thwarted belongingness and perceived burdensomeness may be an important target for reducing suicidal desire.

Acute Substance Use as a Warning Sign for Suicide Attempts: A Case-Crossover Examination of the 48 Hours Prior to a Recent Suicide Attempt.

OBJECTIVE: The extent to which specific categories of acute substance use are short-term risk factors, or warning signs, for suicide attempts is unknown. The aim of the current study was to quantify the near-term effects of sole use and co-use of substances on medically attended suicide attempts. METHODS: The current study used a case-crossover design, comparing substance use within the 24 hours prior to a suicide attempt (case day) to the control day, the matched 24 hours the day prior to the case day. Participants were 363 recent suicide attempters presenting to a Level 1 trauma hospital between October 2008 and April 2014. A timeline follow-back methodology was used to assess acute exposures within the 48 hours before the suicide attempt. Conditional logistic regression was used to report odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Results indicated that patients were at increased odds of attempting suicide after drinking alcohol within a 24-hour period (OR = 4.40; 95% CI, 2.31-8.40) and using a drug from another class of substances with central nervous system (CNS) depressant characteristics (sedatives/anxiolytics and opioids; OR = 2.82; 95% CI, 1.13-7.01), after adjustment for other acute substance use. The acute use of cannabis and CNS stimulants (stimulants/amphetamines and cocaine) was not uniquely associated with suicide attempt. Co-use of alcohol synergized effects of other CNS depressants (OR = 8.76; 95% CI, 1.02-75.44). CONCLUSIONS: Findings suggest the importance of considering acute alcohol use and use of CNS depressants, and the concurrent use of both substances, when evaluating short-term risk for suicide attempts in clinical settings.

Psychiatric heterogeneity of recent suicide attempters: A latent class analysis.

Presence of, and comorbidity between, psychiatric disorders is a risk factor for suicide attempts. No study to date has used a person-centered approach to determine whether there are subgroups of attempters showing differing patterns of psychiatric disorders. This study aimed to identify psychiatric subgroups amongst recent suicide attempters (i.e., hospitalized within 24h of their attempt) and to determine whether identified classes could be differentiated in terms of important clinical correlates. Participants included 97 adult patients who were hospitalized due to a recent suicide attempt at a large Trauma 1 hospital. A structured diagnostic interview assessed a range of psychiatric disorders, and a battery of measures assessed acute and distal clinical correlates and characteristics of the current attempt. The person-centered analytic approach of latent class analysis was used to identify psychiatric diagnostic subgroups, or classes, of attempters. Three psychiatric subgroups were identified: Major Depressive Disorder, High Externalizing Disorders, and High Internalizing High Externalizing Disorders. Classes were found to significantly differ on a range of acute and distal clinical correlates, but not by demographics. Identification of psychiatric subgroups of individuals who have recently attempted suicide has important practical implications for increasing subsequent treatment utilization and tailoring treatment interventions for this population.

Alcohol Policies and Suicide: A Review of the Literature.

Both intoxication and chronic heavy alcohol use are associated with suicide. There is extensive population-level evidence linking per capita alcohol consumption with suicide. While alcohol policies can reduce excessive alcohol consumption, the relationship between alcohol policies and suicide warrants a critical review of the literature. This review summarizes the associations between various types of alcohol policies and suicide, both in the United States and internationally, as presented in English-language literature published between 1999 and 2014. Study designs, methodological challenges, and limitations in ascertaining the associations are discussed. Because of the substantial between-states variation in alcohol policies, U.S.-based studies contributed substantially to the literature. Repeated cross-sectional designs at both the ecological level and decedent level were common among U.S.-based studies. Non-U.S. studies often used time series data to evaluate pre-post comparisons of a hybrid set of policy changes. Although inconsistency remained, the published literature in general supported the protective effect of restrictive alcohol policies on reducing suicide as well as the decreased level of alcohol involvement among suicide decedents. Common limitations included measurement and selection bias and a focus on effects of a limited number of alcohol policies without accounting for other alcohol policies. This review summarizes a number of studies that suggest restrictive alcohol policies may contribute to suicide prevention on a general population level and to a reduction of alcohol involvement among suicide deaths.

Relations Between Nonsuicidal Self-Injury and Suicide Attempt Characteristics in a Sample of Recent Suicide Attempters.

BACKGROUND: Although nonsuicidal self-injury (NSSI) is known to be associated with increased risk of death by suicide and suicide attempts, minimal research has focused on comparing recent suicide attempters with and without NSSI on suicide attempt characteristics (frequency and severity of suicide attempts). Understanding how NSSI impacts suicide attempt characteristics can help providers to enhance their assessment and treatment strategies so as to prevent future suicidal behaviors. AIMS: The present study investigated the extent to which a history of NSSI was related to the frequency and severity of suicide attempts in a sample of recent suicide attempters. METHOD: Participants included 171 adult patients who presented to the hospital within 24 hr of a suicide attempt. Information about their suicide attempts and NSSI was gathered using self-report questionnaires and interviews. RESULTS: Suicide attempters with a history of NSSI reported significantly more suicide attempts and more suicide attempts requiring medical attention, after controlling for important clinical covariates. CONCLUSION: NSSI was uniquely associated with suicide attempt characteristics, highlighting the importance of NSSI in suicide assessment, prevention, and treatment efforts.

A literature review and meta-analyses of cannabis use and suicidality.

BACKGROUND: We lack a review of the epidemiological literature on cannabis use (acute use and chronic-usual quantity/frequency and heavy use) and suicidality (suicide death, suicide ideation, suicide attempt). METHODS: The English language literature on Medline, PsychInfo, Google Scholar, and public-use databases was searched for original articles, critical review reports, and public use data on cannabis use and suicide for the period ranging from 1990-2015 (February). Odds ratios (OR) from random effects in meta-analyses for any cannabis use and heavy cannabis use were calculated. RESULTS: The acute cannabis-suicidality literature mostly includes descriptive toxicology reports. In terms of death by suicide, the average positive cannabis rate was 9.50% for studies sampling from all suicides, with higher cannabis detection rates amongst suicide decedents by non-overdose methods. We found only 4 studies providing estimates for any chronic cannabis use and death by suicide (OR=2.56 (1.25-5.27)). After deleting duplicates we found 6 studies on any cannabis use and suicide ideation (OR=1.43 (1.13-1.83)), 5 studies on heavy cannabis use and suicide ideation (OR=2.53 (1.00-6.39)), 6 studies on any cannabis use and suicide attempt (OR=2.23 (1.24-4.00)) and 6 studies on heavy cannabis use and suicide attempt (OR=3.20 (1.72-5.94)). CONCLUSIONS: We currently lack evidence that acute cannabis use increases imminent risk for suicidality. The evidence tends to support that chronic cannabis use can predict suicidality, but the lack of homogeneity in the measurement of cannabis exposure and, in some instances, the lack of systematic control for known risk factors tempered this finding.