Sherry Stewart
Dalhousie University, Psychiatry, Faculty Member
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Using a multigroup path analysis, we examined if hazardous alcohol use mediated the relations between elevated externalizing personality traits (i.e., impulsivity or sensation seeking) and reduced adherence to COVID-19 public health... more
Using a multigroup path analysis, we examined if hazardous alcohol use mediated the relations between elevated externalizing personality traits (i.e., impulsivity or sensation seeking) and reduced adherence to COVID-19 public health guidelines. We hypothesized that those high in externalizing personality traits would demonstrate less adherence to public health guidelines and that hazardous alcohol use would mediate this relationship. First- and second-year undergraduates ( N = 1232; ages 18–25) from five Canadian universities participated in a cross-sectional survey between January to April 2021. Individuals with higher levels of impulsive or sensation seeking personality traits demonstrated poorer adherence to COVID-19 public health guidelines and these relations were mediated by hazardous alcohol use. Results suggest that hazardous drinking is an important target for students high in impulsivity and sensation seeking to increase their adherence to public health guidelines and ther...
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We extracted items to create a brief version of the COVID‐19 Stress Scale (i.e., CSS‐B) and examined its psychometric properties in young adults. A sample of 1318 first‐ and second‐year undergraduates from five Canadian universities (mean... more
We extracted items to create a brief version of the COVID‐19 Stress Scale (i.e., CSS‐B) and examined its psychometric properties in young adults. A sample of 1318 first‐ and second‐year undergraduates from five Canadian universities (mean [SD] age = 19.27 [1.35] years; 77.6% women) completed an online cross‐sectional survey that included the CSS‐B as well as validated measures of anxiety and depression. The 18‐item CSS‐B fit well on both a 5‐factor and a hierarchical model indicating that the five CSS‐B dimensions may be factors of the same over‐arching construct. The CSS‐B factor structure displayed lower‐order and higher‐order configural and metric invariance across sites but not scalar invariance indicating that the intercepts/means were not consistent across sites. The CSS dimensions were positively related to measures of general anxiety and depression but not so strongly as to indicate that they are measuring the same construct. The CSS‐B scale is a valid measure of COVID‐19 st...
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The complexity and importance of underage drinking prompted ERAB and ABMRF to initiate a state of the art review. It explores the extent of underage drinking across Europe and North America, as well as our current understanding of factors... more
The complexity and importance of underage drinking prompted ERAB and ABMRF to initiate a state of the art review. It explores the extent of underage drinking across Europe and North America, as well as our current understanding of factors that increase the risk of this behaviour and potentially effective evidence-based approaches to prevent underage drinking. Unfortunately, the problem is complex and a single solution or policy to prevent underage drinking does not exist. Nevertheless, a number of strategies are effective in some circumstances and warrant further study in different populations. Preventing risky drinking requires understanding of the important influence of family and peers. It is also important to recognize that some genetic traits like impulsivity, anxiety, sensation seeking and emotional dysregulation can also influence harmful drinking. These aspects (family and peers and genetic influence) are affected by cultural and environmental influences which, in turn, can ...
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ABSTRACT
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Objective Cannabis is commonly used by Canadian emerging adults (ages 18–25 years), many of whom attend post-secondary institutions. Frequent cannabis use is linked with psychotic-like experiences (PLEs); however, the exact nature of this... more
Objective Cannabis is commonly used by Canadian emerging adults (ages 18–25 years), many of whom attend post-secondary institutions. Frequent cannabis use is linked with psychotic-like experiences (PLEs); however, the exact nature of this association remains unclear. Anxiety symptoms may mediate this association, as they are prevalent in emerging adults and have been independently linked with both cannabis use and PLEs. Past work found that anxiety mediated the association between cannabis use frequency and attenuated positive psychotic symptoms (further along the psychosis continuum than PLEs), however this research had yet to be validated in the Canadian population, and trait rather than state anxiety (frequency of anxiety symptoms) was studied. Thus, our primary objective was to examine if anxiety symptoms mediated the association between cannabis use frequency and PLEs in Canadian emerging adult undergraduates. Despite known sex differences in cannabis use, expression of anxiety, and PLEs, past work did not evaluate the potential impact of biological sex on the anxiety-mediated model, and thus is the secondary objective of the present study. Methods 1,266 first-/second-year emerging adult undergraduates from five Canadian universities provided cross-sectional, self-report survey data in fall 2021 semester. Validated measures of cannabis use frequency, anxiety, and PLEs were administered. Results Path analyses supported mediation from cannabis use to PLEs through anxiety ( b = 0.07, P < 0.001, 95% bootstrap CI [0.03, 0.10]). No direct effect was found ( P = 0.457), suggesting that the cannabis-to-PLEs association was mediated by anxiety. Mediation did not depend on biological sex (i.e., bootstrapped 95% CIs crossed zero). Conclusions Anxiety symptoms mediated the association between cannabis use and PLEs in emerging adults regardless of their biological sex. Assuming replication in prospective research, results highlight anxiety as an important intervention target in frequent cannabis-using emerging adults, to potentially prevent development/worsening of PLEs, and in turn psychotic illness.
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ABSTRACT Anxiety sensitivity (AS; i.e. fear of arousal-related sensations) and impulsivity (i.e. tendency to act quickly without regard for longer-term consequences) represent risks for low physical activity participation. Theoretically,... more
ABSTRACT Anxiety sensitivity (AS; i.e. fear of arousal-related sensations) and impulsivity (i.e. tendency to act quickly without regard for longer-term consequences) represent risks for low physical activity participation. Theoretically, higher impulsivity may exacerbate the negative exercise behaviours of high AS individuals given the tendency of impulsive individuals to favour immediate (e.g. watching TV) over delayed rewards (e.g. the benefits of exercise). Our goal was to investigate the main and interactive effects of AS and impulsivity on physical activity levels at varying exercise intensities. Participants were 178 emerging adults (Mean age = 21.9; 68.8% women). Higher AS was associated with less engagement in vigorous intensity exercise. Moderator analyses revealed an AS x impulsivity interaction: high AS predicted significantly less engagement in moderate intensity exercise at low impulsivity levels and marginally more engagement in moderate intensity exercise at high impulsivity levels. Finally, higher impulsivity was associated with more time spent walking. Cognitive behavioural therapy for high AS, or teaching individuals with high AS to focus on immediate, external rewards of exercise, may help them engage in more physical activity. Given the wide-ranging physical and mental health benefits of exercise involvement, developing effective strategies to increase such involvement in high AS individuals is vital.
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BackgroundThe Four Factor Personality Vulnerability model identifies four specific personality traits (e.g., sensation seeking [SS], impulsivity [IMP], anxiety sensitivity [AS], and hopelessness [HOP]) as implicated in substance use... more
BackgroundThe Four Factor Personality Vulnerability model identifies four specific personality traits (e.g., sensation seeking [SS], impulsivity [IMP], anxiety sensitivity [AS], and hopelessness [HOP]) as implicated in substance use behaviors, motives for substance use, and co-occurring psychiatric conditions. Although the relationship between these traits and polysubstance use in opioid agonist therapy (OAT) clients has been investigated quantitatively, no study has examined the qualitative expression of each trait using clients’ voice.MethodNineteen Methadone Maintenance Therapy (MMT) clients (68.4% male, 84.2% white, mean age[SD] = 42.71 [10.18]) scoring high on one of the four personality traits measured by the Substance Use Risk Profile Scale [SURPS] completed a semi-structured qualitative interview designed to explore their lived experience of their respective trait. Thematic analysis was used to derive themes, which were further quantified using content analysis.ResultsThemes...
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Background/Aim: Cannabis is commonly used by Canadian emerging adults (ages 18-25 years), many of whom attend post-secondary institutions. Frequent cannabis use has been linked with psychotic-like experiences (PLEs); however, the exact... more
Background/Aim: Cannabis is commonly used by Canadian emerging adults (ages 18-25 years), many of whom attend post-secondary institutions. Frequent cannabis use has been linked with psychotic-like experiences (PLEs); however, the exact nature of this complex relationship remains to be fully understood. Anxiety is a prevalent mental health concern in emerging adults and university students, and anxiety has been independently linked with both cannabis use and PLEs. Males and females use cannabis and experience mental health differently: females tend to be more anxious while males tend to use more cannabis and are at higher risk for psychotic-like experiences. In this first of two studies for my Masters, I evaluated whether anxiety mediated the relationship between cannabis use frequency and PLEs in emerging adult undergraduates. I then tested the impact of moderation by biological sex by assessing if the mediation model held statistical significance across sexes. Hypotheses: H1) Consu...
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Background. There have been notable increases in the use of cannabidiol (CBD) for therapeutic purposes, such as in the treatment of stress- and anxiety- related disorders. Preliminary research has demonstrated that CBD decreases indices... more
Background. There have been notable increases in the use of cannabidiol (CBD) for therapeutic purposes, such as in the treatment of stress- and anxiety- related disorders. Preliminary research has demonstrated that CBD decreases indices of stress and anxiety. However, drug effects in humans are thought to be comprised of both pharmacological properties as well as a placebo response. Little is known about the extent to which the purported therapeutic effects of CBD result from pharmacological versus expectancy factors. Aims. The aim of this study was to evaluate whether (i) CBD expectancy alone could influence stress, anxiety, and mood, and (ii) the extent to which beliefs regarding CBD effects predicted these responses. Generalized estimating equations (GEE) were used to evaluate the research questions of interest. Methods. In this randomized crossover study, 43 health adults (23 women) attended three laboratory sessions. During the first session, they were oriented to the study and...
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Background Youth and young adults have been significantly impacted by the opioid overdose and health crisis in North America. There is evidence of increasing morbidity and mortality due to opioids among those aged 15–29. Our review of key... more
Background Youth and young adults have been significantly impacted by the opioid overdose and health crisis in North America. There is evidence of increasing morbidity and mortality due to opioids among those aged 15–29. Our review of key international reports indicates there are few youth-focused interventions and treatments for opioid use. Our scoping review sought to identify, characterize, and qualitatively evaluate the youth-specific clinical and pre-clinical interventions for opioid use among youth. Method We searched MedLine and PsycInfo for articles that were published between 2013 and 2021. Previous reports published in 2015 and 2016 did not identify opioid-specific interventions for youth and we thus focused on the time period following the periods covered by these prior reports. We input three groups of relevant keywords in the aforementioned search engines. Specifically, articles were included if they targeted a youth population (ages 15–25), studied an intervention, and...
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Cannabis use is common in individuals with posttraumatic stress disorder (PTSD). The PTSD-cannabis relationship is important as cannabis use can worsen PTSD outcomes. Cannabis use motives are a useful construct for understanding the... more
Cannabis use is common in individuals with posttraumatic stress disorder (PTSD). The PTSD-cannabis relationship is important as cannabis use can worsen PTSD outcomes. Cannabis use motives are a useful construct for understanding the PTSD-cannabis relationship. Frequent pairing of a trauma cue with substance use to cope can lead to conditioned substance craving. The extant research has not yet examined potential mechanisms to explain this effect. We recruited 51 cannabis users with a trauma history for a cannabis cue-reactivity study to examine coping motives as a potential mediator of the hypothesized relationship between PTSD symptoms and cannabis craving to trauma cues. Participants first completed a validated cannabis use motives measure. They were then exposed to a personalized audio and visual cue based on their trauma experience and reported on their cannabis craving immediately following using a standardized measure. Coping motives were contrasted with enhancement motives as ...
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Rationale Cannabidiol (CBD) has been reported to attenuate stress and anxiety, but little is known about the extent to which such effects result from pharmacological versus expectancy factors. Objectives We evaluated whether CBD... more
Rationale Cannabidiol (CBD) has been reported to attenuate stress and anxiety, but little is known about the extent to which such effects result from pharmacological versus expectancy factors. Objectives We evaluated whether CBD expectancy alone could influence stress, anxiety, and mood, and the extent to which beliefs regarding CBD effects predicted these responses. Methods In this randomized crossover study, 43 health adults (23 women) attended two experimental laboratory sessions, where they self-administered CBD-free hempseed oil sublingually. During one session, they were (incorrectly) informed that the oil contained CBD and in the other session, that the oil was CBD-free. Following administration, participants engaged in the Maastricht Acute Stress Test (MAST). Heart rate variability (HRV) was assessed continuously, and subjective state was assessed at baseline, 90-min following oil administration, immediately following the MAST, and after a 10-min recovery period. Results The...
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BACKGROUND Substance use motives (i.e., reasons for using a substance) are thought to be the most proximal variable leading to substance use. These motives have been described by various typologies, the most well known being the... more
BACKGROUND Substance use motives (i.e., reasons for using a substance) are thought to be the most proximal variable leading to substance use. These motives have been described by various typologies, the most well known being the four-factor drinking motives model which separates motives into enhancement, social, coping, and conformity (Cooper, 1994). Although extensively studied in adult community samples, motives for use have less commonly been investigated among populations at a later stage of addiction, where polysubstance use is more common. Moreover, because the motives literature has largely focused on drinking motives, it is not clear whether existing findings can also be applied to other substances (Cooper et al., 2016). METHODS Using Zero-inflated beta Bayesian linear mixed modeling, we investigated the stability of seven distinct substance use motives (enhancement, social, expansion, coping with anxiety, coping with depression, coping with withdrawal, and conformity) across six different drug categories (tobacco, alcohol, cannabis, opioids, stimulants, and tranquilisers) to determine the extent to which drug class can influence motive endorsement. One-hundred-and-thirty-eight methadone maintenance therapy (MMT) clients (F = 34.1%; M = 65.9%; age = 40.18 years) completed a novel short-form polysubstance motives questionnaire. RESULTS External motives (i.e., conformity and social motives) were the most stable across drug categories, while all internal motives (i.e., enhancement, expansion, and all three coping motives) demonstrated varying levels of inter-drug variability. CONCLUSIONS These findings have important implications for prevention and intervention strategies among people who engage in polysubstance use, highlighting the importance of both universal and substance-specific programming.
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Abstract Background: Heavy alcohol consumption and frequent alcohol use are associated with many adverse social and physical consequences. The different motivations underlying why people drink predict different patterns of alcohol... more
Abstract Background: Heavy alcohol consumption and frequent alcohol use are associated with many adverse social and physical consequences. The different motivations underlying why people drink predict different patterns of alcohol consumption. A drinking buddy (i.e. a friend with whom a person drinks alcohol) influences a person’s drinking via social learning, leading to escalations in drinking over time. Purpose: Few studies have investigated drinking motives among peers and none have studied whether the drinking motives of a drinking buddy can influence another person’s drinking behavior; we sought to fill that gap. Method: Same-sex drinking buddies (N = 174; 66.1% female) were assessed once monthly for four months using self-report questionnaires. Participants were on average 18.66 years-old (SD = 1.17). Results: Indistinguishable actor–partner interdependence models using multilevel path analysis were conducted, with each drinking motive predicting drinking frequency and quantity, respectively. There were significant actor effects for social, enhancement, conformity, and coping motives; moreover, the enhancement, social, and coping-anxiety motives of the drinking buddy influenced the individual’s drinking frequency across the four months of the study. Conversely, only the enhancement motives of the buddy predicted drinking quantity in the individual when averaged across time. Sex was not a significant moderator of these effects. Importance: When targeting risky drinking behavior in a therapeutic context, assessing and addressing a person’s reasons for drinking, as well as their drinking buddy’s reasons for drinking, may reduce the risk of escalations in either friend’s drinking frequency over time.
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Excessive alcohol consumption is related to adverse physical and social consequences. Research shows an individual’s own drinking motives (reasons for drinking alcohol) are linked to his or her specific drinking outcomes in a... more
Excessive alcohol consumption is related to adverse physical and social consequences. Research shows an individual’s own drinking motives (reasons for drinking alcohol) are linked to his or her specific drinking outcomes in a theoretically expected manner. Romantic couples often engage in a “drinking partnership,” where partners reciprocally influence each other’s drinking. Though alcohol consumption partner effects have been studied, partner effects of drinking motives on an individual’s alcohol consumption have not been investigated in romantic couples. We investigated this topic. Romantic couples (N = 203) were assessed once weekly for four weeks using self-report questionnaires. Participants were on average 22.7 years old (SD = 5.5) and were in their relationship an average of 2.3 years (SD = 2.4). Actor-partner interdependence models using multilevel path-analysis with indistinguishable dyads were conducted, with each motive predicting drinking quantity and frequency. There were significant actor effects for social and enhancement motives; moreover, changes in a partner’s enhancement and social motives predicted change in the individual’s drinking quantity during any given week, but only averaged partners’ enhancement motives predicted the individual’s drinking frequency. Coping-with-anxiety motives had significant actor effects when predicting averaged quantity and frequency; moreover, changes in partners’ coping-with-anxiety motives predicted changes in drinking quantity. Enhancement and social motives of the partner influenced the drinking quantity and frequency of the actor by way of influencing the actor’s enhancement and social motives. Intervention efforts targeting both members of a romantic dyad on their reasons for drinking should be tested for preventing escalations in either member’s drinking behavior.
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Dual process models propose that behaviour is influenced by the interactive effect of impulsive (i.e., automatic or implicit) and self-regulatory (i.e., controlled or explicit) processes. Recently, evidence from the alcohol literature... more
Dual process models propose that behaviour is influenced by the interactive effect of impulsive (i.e., automatic or implicit) and self-regulatory (i.e., controlled or explicit) processes. Recently, evidence from the alcohol literature demonstrates that the impulse to engage in risky behaviour is mitigated by a high capacity to self-regulate. The current study aimed to extend this model to behavioural addictions, namely frequent gambling behaviour. It was hypothesized that impulsive processes favouring gambling (positive implicit gambling cognition) would predict frequent gambling, but only if the capacity to self-regulate was low. A treatment-seeking sample of 57 adults with problem gambling (Mage = 45.20 years, 54% men) completed two Single Category Implicit Association Tests, one reflecting tension-reduction, and the other enhancement, implicit gambling cognition. Participants also completed self-report measures of past week gambling frequency and the Gambling Abstinence Self-Effi...
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Alcohol intoxication is often involved for both victims and perpetrators of sexual victimization. Yet, alcohol-involved sexual victimization research has mainly focused on female victims, excluding male victims. The current study... more
Alcohol intoxication is often involved for both victims and perpetrators of sexual victimization. Yet, alcohol-involved sexual victimization research has mainly focused on female victims, excluding male victims. The current study addresses gaps in the literature by focusing on sex differences in the emotional harms (anxiety and depression symptomatology) experienced by sexual victimization victims when either the perpetrator or victim was drinking. Five-hundred-and-ten undergraduate drinkers (153 male; 357 female) participated. Models included two dichotomized predictors that occurred during participants’ first year of university (sexually victimized when the victim was drinking, sexually victimized by someone who was drinking), and two emotional outcomes (anxiety, depression). Age was controlled in all path analyses and sex was examined as a moderator. When predictors were examined in separate models, both predictors were associated with increased anxiety but not depression. These ...
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To explain the co-occurrence of social anxiety and alcohol use problems, researchers have used experimental methods to test whether alcohol reduces state social anxiety (SSA) in the lab. The present study used experience sampling to... more
To explain the co-occurrence of social anxiety and alcohol use problems, researchers have used experimental methods to test whether alcohol reduces state social anxiety (SSA) in the lab. The present study used experience sampling to extend research into real world settings. Students (N = 132; 100 women; 32 men; aged 17 to 32 years) reported their SSA and alcohol intake 6 times from 4:00 pm to 4:00 am every day for 22 days. Multilevel modeling suggested for each alcoholic drink consumed, SSA decreased by 4.0% two hours later. Those with greater levels of trait social anxiety (TSA) experienced higher SSA than those with lower levels of TSA. Findings support predictions made by tension reduction theory—that alcohol reduces SSA in daily life. These results extend many lab-based findings to the real world and provide further evidence that alcohol may provide negative reinforcement for those who are experiencing social anxiety.
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Background and aimsProblem gambling and tobacco use are highly comorbid among adults. However, there are few treatment frameworks that target both gambling and tobacco use simultaneously (i.e., an integrated approach), while also being... more
Background and aimsProblem gambling and tobacco use are highly comorbid among adults. However, there are few treatment frameworks that target both gambling and tobacco use simultaneously (i.e., an integrated approach), while also being accessible and evidence-based. The aim of this two-arm open label RCT was to examine the efficacy of an integrated online treatment for problem gambling and tobacco use.MethodsA sample of 209 participants (Mage = 37.66, SD = 13.81; 62.2% female) from North America were randomized into one of two treatment conditions (integrated [n = 91] or gambling only [n = 118]) that lasted for eight weeks and consisted of seven online modules. Participants completed assessments at baseline, after treatment completion, and at 24-week follow-up.ResultsWhile a priori planned generalized linear mixed models showed no condition differences on primary (gambling days, money spent, time spent) and secondary outcomes, both conditions did appear to significantly reduce probl...
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Background and aimsMany new digital gambling-like activities such as loot boxes, esports betting, skin betting, and token wagering have recently emerged and grown in popularity. This scoping review aimed to: (a) synthesize the existing... more
Background and aimsMany new digital gambling-like activities such as loot boxes, esports betting, skin betting, and token wagering have recently emerged and grown in popularity. This scoping review aimed to: (a) synthesize the existing empirical research literature on gambling-like activities and their associations with gambling and video gaming behaviors, including problem gambling and video gaming; (b) identify sociodemographic, psychological, and motivational factors associated with engagement in gambling-like activities; and (c) identify research gaps and areas for further research.MethodsA systematic search of Ovid, Embsco, and ProQuest databases and Google Scholar was conducted in May 2021 and last updated in February 2022. The search yielded a total of 2,437 articles. Articles were included in the review if they were empirical studies that contained quantitative or qualitative results regarding the relationship between gambling-like activities and gambling or gaming.ResultsTh...
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We investigated whether anxiety sensitivity (AS) is associated with increased distress and adherence to public health guidelines during the COVID-19 pandemic among undergraduates, and whether increased distress mediates the relationship... more
We investigated whether anxiety sensitivity (AS) is associated with increased distress and adherence to public health guidelines during the COVID-19 pandemic among undergraduates, and whether increased distress mediates the relationship between AS and increased adherence. An online cross-sectional survey was conducted with 1318 first- and second-year undergraduates (mean age of 19.2 years; 79.5% females) from five Canadian universities. Relevant subscales of the Substance Use Risk Profile Scale (SURPS) and the Big Five Inventory-10 (BFI-10) were used to assess AS and neuroticism. Three measures tapped distress: the Patient Health Questionnaire-9 (PHQ-9) for depressive symptoms, the Generalized Anxiety Disorder-7 (GAD-7) for anxiety symptoms, and the Brief COVID-19 Stress Scales (CSS-B) for COVID-19-specific distress. The COVID-19 Adherence scale (CAD) assessed adherence to COVID-19 containment measures. AS was significantly independently associated with higher general distress (both...
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Objectives: Social media (SoMe) is globally prevalent, but its relevance for disseminating sensitive topics, such as violence victimization and mental health among adolescents and emerging adults, remain under-researched. Youth-dominate... more
Objectives: Social media (SoMe) is globally prevalent, but its relevance for disseminating sensitive topics, such as violence victimization and mental health among adolescents and emerging adults, remain under-researched. Youth-dominate platforms may be well-suited for resilience messaging on safety, health, and well-being, and exploratory knowledge mobilization research. Research from a common team funding source supported a secondary objective that thematically linked research could be used to impact dissemination. Methods: This experiment utilized an ABA design, with a two-week baseline, followed by SoMe posting on weeks "A" and no posting on weeks "B" from a single Instagram account. During posting weeks, image-based messages from nine open access articles, from a risk and resilience research team, were posted three times per day. Each post contained a link to the associated open-access research article. Outcome dissemination indices, collected weekly, were r...