Matthew Pearson’s research while affiliated with University of New Mexico and other places

Objective: Due to little knowledge regarding the contextual factors related to cannabis use, we aimed to provide descriptive statistics regarding contextual factors related to use and examine the predictive ability of contextual factors. Method: We included college student participants (n = 5700; male = 2893, female = 3702, other gender identity = 48, missing = 57) from three multi-site studies in our analyses. We examined the means and standard deviations of contextual factors related to cannabis use (social context/setting, form of cannabis, route of administration, source of purchase, and proxies of use). Additionally, we tested the predictive ability of the contextual factors on cannabis use consequences, protective behavioral strategies, and severity of cannabis use disorder, via an exploratory machine learning model (random forest). Results: Descriptive statistics and the correlations between the contextual factors and the three outcomes are provided. Exploratory random forests indicated that contextual factors may be helpful in predicting consequences and protective behavioral strategies and especially useful in predicting the severity of cannabis use disorder. Conclusions: Contextual factors of cannabis use warrants further exploration, especially considering the difficulty in assessing dosage when individuals are likely to consume in a group context. We propose considering measuring contextual factors along with use in the past 30 days and consequences of use.

American Indian/Alaska Native (AI/AN) individuals have the highest rates of opioid overdose mortality and chronic pain (CP) compared to other racial/ethnic groups in the United States. These individuals also report higher rates of pain anxiety and pain catastrophizing, which are both associated with poorer outcomes and risk for opioid misuse (OM) and opioid use disorder (OUD) among individuals with CP. Yet, no prior studies have examined rates of comorbid pain and OUD among AI/AN adults. This commentary describes an implementation research partnership of 3 AI/AN-serving clinics and a university team that utilizes an implementation hybrid type III design to examine the impact of implementation strategies on adoption and sustainability of evidence-based screening and brief intervention for CP and OM/OUD among AI/AN clients. As part of our community-engaged approach, we embrace both AI/AN models and Western models, and a collaborative board of 10 individuals guided the research throughout. We hypothesize that our culturally centered approach will increase rates of screening and brief intervention and improve identification of and outcomes among AI/AN clients with CP and OUD who receive treatment at participating sites. Each site convenes a workgroup to evaluate and set goals to culturally center screening and brief interventions for CP and OM/OUD. Data collected include deidentified electronic health records to track screening and brief interventions and rates of CP and OUD; provider and staff surveys beginning prior to implementation and every 6 months for 2 years; and a subset of clients will be recruited (N = 225) and assessed at baseline, 6, and 12 months to examine biopsychosocial and spiritual factors and their experiences with culturally centered screening and brief intervention. Cultural adaptations to the measures and screening and brief intervention as well as barriers and facilitators will be addressed. Recommendations for successful Tribal health clinic-university partnerships are offered.

Background: Anxiety is implicated in the course and prognosis of alcohol use disorder (AUD); however, it is unclear how current AUD treatments affect the joint trajectories of anxiety and alcohol use. We used data from the Combined Pharmacotherapies and Behavioral Interventions for Alcohol Dependence (COMBINE) study to examine the longitudinal relationship between subclinical anxiety symptoms and alcohol use during and following AUD treatment in adults with AUD and no comorbid anxiety disorders. Methods: Univariate and parallel process growth models using five waves of COMBINE study data were analyzed from 865 adults randomized to medication (n = 429) or medication plus psychotherapy (n = 436). Weekly drinking quantity and average weekly anxiety symptoms were measured at baseline, mid-treatment, end-of-treatment, and three follow-up periods. Results: Significant positive associations of anxiety symptoms and drinking were found at mid-treatment and over time. Temporal associations revealed that higher mid-treatment anxiety predicted decreases in drinking over time. Baseline anxiety and drinking predicted mid-treatment anxiety and drinking. Only baseline anxiety predicted increases in drinking over time. Group differences revealed mid-treatment drinking predicted decreases in anxiety over time in the medication group. Conclusions: Findings demonstrate the influence of subclinical anxiety on alcohol use during and up to one year after AUD treatment. Baseline anxiety symptoms may influence drinking behavior over the course of treatment. Findings suggest that greater attention to negative affect in AUD treatment is warranted even for those individuals who do have a comorbid anxiety disorder.

Background: Understanding, predicting, and reducing the harms associated with cannabis use is an important field of study. Timing (i.e., hour of day and day of week) of substance use is an established risk factor of severity of dependence. However, there has been little attention paid to morning use of cannabis and its associations with negative consequences. Objectives: The goal of the present study was to examine whether distinct classifications of cannabis use habits exist based on timing, and whether these classifications differ on cannabis use indicators, motives for using cannabis, use of protective behavioral strategies, and cannabis-related negative outcomes. Methods: Latent class analyses were conducted on four independent samples of college student cannabis users (Project MOST 1, N=2,056; Project MOST 2, N=1846; Project PSST, N=1,971; Project CABS, N=1,122). Results: Results determined that a 5-class solution best fit the data within each independent sample consisting of the classes: (1) "Daily-morning use",(2) "Daily-non-morning use", (3) "Weekend-morning use", (4) "Weekend-night use", and (5) "Weekend-evening use." Classes endorsing daily and/or morning use reported greater use, negative consequences and motives, while those endorsing weekend and/or non-morning use reported the most adaptive outcomes (i.e., reduced frequency/quantity of use, fewer consequences experienced, and fewer cannabis use disorder symptoms endorsed). Conclusions: Recreational daily use as well as morning use may be associated with greater negative consequences, and there is evidence that most college students who use cannabis do avoid these types of use. The results of the present study offer evidence that timing of cannabis use may be a pertinent factor in determining harms associated with use.

While there is evidence that histories of adverse childhood experiences (ACEs) are common in university students and are associated with an increased risk of mental health difficulties, current research has limited geographic and cross-cultural representation. Comparing ACEs across diverse contexts using a standardized measure can illuminate geographic and sociocultural similarities or differences in exposure. The present study aimed to assess ACE exposure and its relationship with mental health symptoms in university students from seven countries. We sampled 5945 university students from the United States, Canada, England, South Africa, Spain, Argentina, and Uruguay. Participants completed the Adverse Childhood Experiences International Questionnaire (ACE-IQ) and the Inventory of Depression and Anxiety Symptoms (IDAS). Most participants (94.8%) reported exposure to at least one type of ACE and 61% reported exposure to four or more types. Repeated exposure to at least one ACE was reported by 70.2% and repeated exposure to at least four ACEs was reported by 21.2%. Spanish students had significantly lower ACE exposure than other students. Cumulative ACE exposure was significantly higher among students in lower income countries, but when repeated exposure was considered these differences fell away. For the total sample, cumulative ACE exposure was significantly associated with severity of depression symptoms, anxiety symptoms, and suicidality. Findings indicate that universities globally should be guided by a trauma-informed approach that recognizes students as a psychologically vulnerable group carrying a long-standing burden of childhood adversity.

Negative consequences associated with excessive use of cannabis are well documented. Previous findings indicate timing of use is an important factor when assessing severity of dependence for use of substances including alcohol and cigarettes. However, little attention in the academic literature has been paid to timing of cannabis use and its associations with negative consequences. The present study employed a latent class analysis on data collected from college students who use cannabis, located across four U.S. universities in four different states (N = 1,122). The goal was to examine whether distinct classifications of cannabis use exist based on timing (i.e., hour of day and day of week), and whether these classifications differ on cannabis use indicators (Marijuana Use Grid; MUG), cannabis-related negative consequences (Marijuana Consequences Questionnaire; MACQ), and cannabis use disorder symptoms (Cannabis Use Disorder Identification Test-Revised; CUDIT-R). The MUG assesses the amount (in grams) of cannabis used during a week of typical marijuana use in the past 30 days on each of the seven days per week (Monday-Sunday) during each of six 4-hour time periods (12a-4a, 4a-8a, 8a-12p, 12p-4p, 4p-8p, 8p-12p). By summing across time periods for each day, we binarized the presence of cannabis use (0 = no use, 1 = use) for each day of the week. By summing across days for each time period, we binarized the presence of cannabis use for each time period. Based on the Lo-Mendell-Rubin Likelihood Ratio Test (LRT) and other fit indices, we found support for a 4-class solution with high classification precision (relative entropy = .905). The four classes were characterized as follows: (1) daily (greater than 98% of the class endorsed use on each day of the week), common morning use (N = 140.17, 12.5%), (2) daily (greater than 88% of the class endorsed use each day of the week), uncommon morning use (N = 241.02, 21.5%), (3) weekend, common morning use (N = 72.22, 6.4%), and (4) weekend, uncommon morning use (N = 668.59, 59.6%). Individuals reporting daily, common morning use experienced the highest cannabis-related negative consequences (MACQ M = 7.53) and reported the highest levels of cannabis use disorder symptoms (CUDIT-R M = 15.74), whereas individuals reporting weekend, uncommon morning use experienced few cannabis-related negative consequences (MACQ M = 2.24)) and reported low cannabis use disorder symptoms (CUDIT-R M = 5.45). Taken together, our classes were defined by crossing the presence/absence of morning cannabis use by the presence/absence of weekday cannabis use, and we found evidence that both the timing of week and timing of day contribute to the level of cannabis-related harms that individuals experience. Additional research is needed to explore the unique contributions of time of week and time of day while controlling for other characteristics of one’s cannabis use (i.e., frequency, quantity, product type, route of administration, etc.).

Findings from national surveys demonstrate that cannabis use peaks in young adulthood and that the annual prevalence of marijuana use among young adults (34.0%) is the highest it has been in decades (Johnston et al., 2016). We developed a 13 item measure designed to characterize the 11 symptoms of CUD as described in the DSM 5 (APA, 2013). To evaluate the performance of this Self Reported Symptoms of Cannabis Use Disorder (SRSCUD) measure, we examined its associations with other measures of CUD symptoms, negative cannabis related consequences, and other known risk factors for CUD (i.e., coping motives). Colleges students (n =7000) recruited from 9 universities in 9 states throughout the U.S. Our analyses focus on past month cannabis users (n = 2077). We split our sample in half to conduct exploratory factor analysis (EFA,n = 1011) and confirmatory factor analysis (CFA, n = 1012). All items loaded saliently on a single factor of CUD symptoms in both EFA (.553 = λ = 805) and CFA models (.524 = λ = 830) (see Table 1). In our final model, we allowed correlated errors between the two indicators of tolerance (items 10 and 11) and the two indicators of withdrawal (items 12 and 13), and obtained acceptable model fit across most indices: CFI = .941, TLI = .927, RMSEA = .059, SRMR = .042. As shown in Table 2, the total score of the SRSCUD was strongly correlated with other CUD symptoms measures (.617 < r s < .697), demonstrating convergent validity. SRSCUD was moderately positively correlated with a well known risk factor for CUD (coping motives) and moderately negative correlated with a well known protective (cannabis protective behavioral strategies). We conducted receiver operator characteristic (ROC) curve analyses to identify well how our continuous measure of CUD symptoms could identify individuals who exceed the cutoffs for probable CUD on these other symptom measures. For the most well validated measure (CUDIT R), we had excellent sensitivity/specificity (mean score of 1.5 on SRSCUD) for predicting probable CUD. Although more research evaluating performance of the SRSCUD compared to a clinical diagnosis is needed, we have preliminary evidence for construct validity of this measure.

The purpose of the present study was to replicate and extend tests of interaction effects between cannabis protective behavioral strategies use and a wide range of risk/protective factors for cannabis-related consequences. We recruited 2,226 college students (Mage = 20.28, SD = 3.37; 68.8% female; 75.4% white) from 10 universities throughout the U.S. who reported using cannabis in the past month to complete an online survey. Measures included in the survey assessed cannabis use, cannabis-related consequences, cannabis protective behavioral strategies use, and 35 risk/protective factors (including socio-demographic characteristics [e.g., biological sex]). Cannabis protective behavioral strategies use was negatively correlated with cannabis-related consequences while controlling for the risk/protective factors. Most importantly, 33% and 54% of the interaction effects tested were statistically significant, depending on the covariates entered into the model. The interaction effects had a consistent pattern such that the positive association between greater risk and cannabis-related consequences was weaker as cannabis protective behavioral strategies use increased. These findings suggest that none of these interaction effects are particularly specific for any given risk/protective factor. We draw parallels to research on alcohol protective behavioral strategies and offer suggestions for moving the cannabis protective behavioral strategies field forward.

Cannabis-related protective behavioral strategies (PBS) are behaviors used before, during, and/or after using cannabis to reduce its associated harms. Despite the effectiveness of PBS in reducing both cannabis use and negative cannabis-related consequences, few studies have examined whether there are sex and cultural differences in PBS use. In the present study, we compare PBS use across males and females and across five countries. We also examine whether the associations of PBS use with cannabis-related outcomes differ by sex and country. We recruited 1,175 college students (63.3% female; Mage = 20.96, SD = 3.95; 45.1% Freshman, 20.2% Sophomore, 16.6% Junior, 9.7% Senior, 8.4% other) who reported past-month cannabis use from eight universities in five countries (U.S., Spain, Argentina, Uruguay, and the Netherlands) to complete an online survey. The online survey included the Marijuana Use Grid (MUG; Pearson & Marijuana Outcomes Study Team, 2020), Protective Behavioral Strategies for Marijuana scale (PBSM; Pedersen et al., 2016; revised by Pedersen et al., 2017), and Brief-Marijuana Consequences Questionnaire (B-MACQ; Simons et al., 2012). Results of a series of ANOVAs suggested differences across countries on the PBSM total score, F(4, 1,126) = 20.93, p < .001, such that participants in the U.S. (M = 4.53, SD = 1.11) and Spain (M = 4.48, SD = 0.95) endorsed the most frequent PBS use and participants in the Netherlands (M = 3.46, SD = 1.49) endorsed the least frequent PBS use. There were many item-level differences in PBS use across countries with a pattern similar to that for the PBSM total score. Results of a series of independent sample t-tests suggested that females (M = 4.51, SD = 1.11) scored higher than males (M = 4.17, SD =1.09) on the PBSM total score, t(1,123) = -4.88, p < .001, as well as nearly every item. The correlations between PBSM total score and cannabis-related outcomes across gender and countries were mostly in the expected direction: more frequent PBS use was associated with less cannabis use and fewer cannabis-related consequences. These correlations were largest for the U.S. sample. Interestingly, however, the correlation between the PBSM total score and B-MACQ was positive for the Argentina sample and every correlation between the PBSM total score and cannabis-related outcome was positive for the Netherlands sample. The results of the present study suggest there are several gender and cultural differences in the use of cannabis-related PBS. However, future studies are needed to replicate these findings, especially given the relatively small samples for some of the countries in the present study (our smallest sample size was for Uruguay [n = 46]). Gender and cultural differences in PBS use should be considered in developing and tailoring PBS interventions, especially because the PBSM was validated with a U.S. sample and most existing interventions were developed for use with U.S. participants.