Recent research highlights that abstaining from cannabis for 28 days can lead to significant cognitive improvements and changes in brain activation among people with multiple sclerosis (MS). This study, presented by Omar Iqbal Khan, MD, emphasises the potential benefits of cannabis abstinence on the default mode network (DMN), which plays a crucial role in modulating cognition.

Key Findings

Cognitive Improvements: The cannabis withdrawal group exhibited significant improvements in multiple cognitive domains by the end of the 28-day period. These improvements underscore the potential cognitive benefits of abstaining from cannabis for individuals with MS.

Day 28 Differences:

• CW Group vs. CC Group: By day 28, the CW group showed increased activation in the left posterior cingulate and right angular gyrus (p < 0.05 for both, TFCE).
• Within CW Group: The CW group exhibited increased activation at day 28 versus baseline in the left posterior cingulate, right angular gyrus, left hippocampus (BA 36), and right medial prefrontal cortex (p < 0.05).

Implications for the Default Mode Network (DMN): The DMN is known to modulate cognition, and the study revealed enhanced DMN activity following cannabis abstinence. This finding provides objective evidence supporting the cognitive benefits of abstaining from cannabis for individuals with MS.

Summary: The study concluded that abstaining from cannabis for 28 days can reverse the activation of DMN activity and lead to improved cognition across several domains in people with MS. These findings offer valuable insights for counselling patients with MS and cognitive complaints about the potential benefits of cannabis abstinence.

Source: PracticeUpdate

Adolescent polysubstance use, particularly among youth with early-onset cannabis use (CU), is a growing concern. This article delves into a study that examines the various polysubstance use profiles among adolescents with early-onset CU and how these profiles impact CU outcomes in early adulthood.

Study Overview: The study aimed to determine whether outcomes in early adulthood are best explained by early-onset CU itself or by resulting polysubstance use profiles. Conducted as part of the Québec Longitudinal Study of Child Development, the research analysed data from 794 participants who reported lifetime CU by age 21.

Participants: Participants were stratified into three groups based on the age of CU onset:

• Early-Onset CU: 349 participants who began using cannabis at age 15 or younger.
• Later Adolescent-Onset CU: 359 participants who began using cannabis between ages 16 and 18.
• Adult-Onset CU: 86 participants who began using cannabis at age 19 or older.

Methodology: Self-reported substance use data were collected from the early-onset CU group at ages 15 and 17, while CU frequency and problem CU were assessed at age 21 for all participants. Repeated measures latent profile analyses were used to identify distinct polysubstance use profiles within the early-onset CU group.

Key Findings

Polysubstance Use Profiles: Four distinct polysubstance use profiles were identified among youth with early-onset CU:

1. Light Users: 54% of the early-onset group.
2. Escalating Users: 13% of the early-onset group.
3. Frequent Users (Without Cigarettes): 14% of the early-onset group.
4. Frequent Users (With Cigarettes): 19% of the early-onset group.

Cannabis Use Outcomes at Age 21: The study found significant differences in CU outcomes at age 21 based on these profiles: 

Escalating and Frequent (With Cigarettes) Users: These individuals showed consistently greater CU frequency and problem CU compared to those in the later adolescent-onset or adult-onset CU groups.

Implications: The findings suggest that early-onset CU is not a homogenous behaviour but rather follows distinct polysubstance use trajectories. These trajectories are differentially associated with the risk for future problem CU, highlighting the need for targeted interventions based on specific usage profiles.

Conclusion: The study provides crucial insights into the diverse polysubstance use patterns among adolescents with early-onset CU and underscores the importance of considering these profiles when addressing CU outcomes in early adulthood.

Source: Springer

Cannabis use disorder (CUD) and cannabis use (CU) are significant conditions frequently co-occurring with attention-deficit hyperactivity disorder (ADHD). A recent genome-wide association study (GWAS) has shed light on the genetic overlap between ADHD and these cannabis-related conditions. This article delves into the study’s findings, highlighting the genetic loci associated with these disorders and their implications for understanding the comorbidity of ADHD and CUD or CU.

Genetic Overlap Between ADHD and Cannabis Use Disorders: The GWAS identified 36 genome-wide significant loci that are concordant for both ADHD and CUD, and ten loci for ADHD and CU. One of the key risk genes identified for ADHD-CUD is DRD2. The study found that ADHD-CUD risk genes exhibited high expression levels across various brain tissues and developmental stages, a pattern not observed in ADHD-CU genes.

Genetic Correlations and Substance Use: ADHD-CUD and ADHD-CU demonstrated similar genetic correlations with substance use; however, they differed significantly when it came to substance-use disorders. This differentiation underscores the complexity of the genetic interplay between ADHD and cannabis-related disorders.

Polygenic Scores (PGS) and Psychiatric Disorders: Individuals with ADHD-CUD showed increased polygenic scores for psychiatric disorders compared to those with ADHD alone. Moreover, they also exhibited a higher burden of rare deleterious variants. These findings suggest that the genetic underpinnings of ADHD-CUD may contribute to a broader spectrum of psychiatric comorbidities.

Risk Stratification: The stratification of individuals with ADHD by their CUD PGS revealed stark differences in the risk of developing comorbid CUD. Those in the highest CUD-PGS bin faced an absolute risk of 22% for comorbid CUD, which is substantially higher than the 1.6% risk observed among control individuals without ADHD.

Implications: These findings provide critical insights into the genetic factors contributing to the co-occurrence of ADHD and cannabis use disorders. Understanding these genetic overlaps can inform targeted interventions and personalised treatment strategies for individuals at high risk of developing these comorbid conditions.

Source: Nature

Introduction: Cannabis use and cannabis use disorder (CUD) are associated with adverse psychosocial outcomes, but their impact on workplace absenteeism remains poorly understood. Moreover, few studies have examined the role of CUD severity. This study aims to address these gaps by examining the associations between cannabis use recency, frequency, CUD severity, and workplace absenteeism.

Methods: Cross-sectional data from a U.S. representative sample of full-time employed adults aged ≥18 from the 2021 to 2022 National Survey on Drug Use and Health (N=46,499) were analyzed. The associations between cannabis use recency, past-month cannabis use frequency, CUD severity, and workplace absenteeism (measured by self-reported number of missed days due to illness/injury and skipped work in the last 30 days) were evaluated using negative binomial regression, adjusting for sociodemographic characteristics and other substance use. Data were analyzed in 2023–2024.

Results: An estimated 15.9% of full-time employed adults used cannabis in the past month, with 6.5% meeting CUD criteria. Past-month cannabis use (compared to no lifetime use), more frequent past-month cannabis use (compared to no use in the past month), and each level of CUD (compared to no CUD) were associated with increased incidence of both missing work due to illness/injury and skipping work, with a dose-response relationship observed between CUD severity and skipping work (mild: adjusted incident rate ratio [aIRR]=1.60 [95% confidence interval [CI]=1.24, 2.08]; moderate: aIRR=1.98 [95% CI=1.50, 2.61]); severe (aIRR=2.87 [95% CI=2.12, 3.88]).

Conclusions: Individuals with recent and frequent cannabis use and CUD are disproportionately prone to workplace absenteeism. Results support the enforcement of workplace drug prevention and treatment policies.

(Source: https://www.sciencedirect.com/science/article/abs/pii/S0749379724002587) 

The placebo effect is a fascinating phenomenon where a person experiences real changes in their health after receiving a treatment that has no therapeutic value. This effect is particularly notable in pain management.

When a person believes they are receiving a pain-relieving treatment, their brain can release natural painkillers called endorphins. These chemicals interact with the brain’s pain pathways, reducing the perception of pain. This process is known as placebo analgesia.

Research has shown that the placebo effect can be as effective as actual pain medications in some cases. For instance, studies have found that patients receiving a placebo can experience pain relief comparable to those taking low doses of morphine. This effect is not just about positive thinking; it involves complex neurobiological reactions, including increased activity in brain regions associated with mood and self-awareness….

When it comes to cannabis, the problem is that we need to create the placebo effect whilst disconnecting the patient from the substance that may have many other negative side-effects beyond the pain issue, which cannabis most certainly has.

For complete article