Short-term residual effects of smoked cannabis on simulated driving performance.

Rationale: Between periods of use, chronic cannabis consumers may display residual effects on selective cognitive functions, particularly memory and attention. Whether there are comparable deficits in real-world behaviors, such as driving, has not been thoroughly examined.

Objectives: The current study explored the association between driving simulator performance, cannabis use history, and demographic factors after ≥ 48 h of abstinence.

Factors associated with driving simulator performance in vocational drivers with HIV.

Neurocognitive symptoms persist in many people living with HIV (PLWH). Safe driving practices are dependent on intact cognition. Research in the general driving population suggests that PLWH with neurocognitive impairment (NCI) perform worse on driving assessment tasks than cognitively intact PLWH.

Medicinal and combined medicinal/recreational cannabis use in California following the passage of Proposition 64.

Background: Proposition 64, the Adult Use of Marijuana Act of 2016, reshaped cannabis use in California. This study explores the use patterns of people who use cannabis for medicinal-only and combined medicinal and recreational use after implementation of Proposition 64.

Methods: A quantitative, population-based online questionnaire included 4,020 current cannabis users, 523 former users, and 635 non-users.

Knowledge and attitudes toward recreational cannabis legalization among California residents: a population-matched questionnaire about Proposition 64.

Background: Implemented in 2018, Proposition 64: The Adult Use of Marijuana Act (Prop 64; passed in 2016) legalized adult recreational cannabis use in California. This analysis of the Impact 64 study aimed to assess knowledge about Prop 64 and attitudes toward cannabis legalization by California residents.

Methods: A mixed qualitative and quantitative questionnaire about cannabis and Prop 64 was completed by 4,020 current cannabis users, 523 former users, and 635 non-users who were selected from an initial pool demographically matched to the 2020 California census.

Cannabis Use in California Following Legalization of Recreational Use.

Cannabis was legalized in California for recreational use through the passage of Proposition 64: The Adult Use Marijuana Act of 2016. This analysis from the Impact 64 study describes the cannabis use patterns of adults 21 years and older in California since the passage of Proposition 64. An online questionnaire addressing use of tetrahydrocannabinol-containing cannabis (including frequency, product(s), length, source, and purpose) was administered from December 2022 to February 2023.

Cannabidiol (CBD) Treatment for Severe Problem Behaviors in Autistic Boys: A Randomized Clinical Trial.

Open-label and observational studies suggest cannabidiol (CBD) reduces problematic behaviors in autistic children. No controlled clinical trials have addressed safety, tolerability, and efficacy. We conducted a double-blind, placebo-controlled crossover study of plant-derived CBD (Epidiolex®) to determine safety, tolerability, and behavior effects in autistic boys.

California Cannabis Research Briefing, April 2023: Meeting Summary.

On April 28, 2023, the University of California Office of the President, in partnership with the California Department of Cannabis Control (DCC), hosted the California Cannabis Research Briefing. The California Cannabis Research Briefing brought together researchers and state agencies/policymakers to discuss pertinent policy issues on cannabis within the state. Researchers across six different topic areas (environment, cannabis markets, social equity matters, public health, medicinal cannabis use, and public safety) provided brief explanations of their research and its policy implications.

Vaporized Cannabis versus Placebo for Acute Migraine: A Randomized Controlled Trial.

Background: Preclinical and retrospective studies suggest cannabinoids may be effective in migraine treatment. However, there have been no randomized clinical trials examining the efficacy of cannabinoids for acute migraine.

Methods: In this randomized, double-blind, placebo-controlled, crossover trial, adults with migraine treated up to 4 separate migraine attacks, 1 each with vaporized 1) 6% Δ9-tetrahydrocannabinol (THC-dominant); 2) 11% cannabidiol (CBD-dominant); 3) 6% THC+11% CBD; and 4) placebo cannabis flower in a randomized order.

Evaluation of Field Sobriety Tests for Identifying Drivers Under the Influence of Cannabis: A Randomized Clinical Trial.

Importance: With increasing medicinal and recreational cannabis legalization, there is a public health need for effective and unbiased evaluations for determining whether a driver is impaired due to Δ9-tetrahydrocannabinol (THC) exposure. Field sobriety tests (FSTs) are a key component of the gold standard law enforcement officer-based evaluations, yet controlled studies are inconclusive regarding their efficacy in detecting whether a person is under the influence of THC.

Objective: To examine the classification accuracy of FSTs with respect to cannabis exposure and driving impairment (as determined via a driving simulation).

Variable Delta-9-Tetrahydrocannabinol Pharmacokinetics and Pharmacodynamics After Cannabis Smoking in Regular Users.

Background: Despite its federally restricted status, cannabis is widely used medicinally and recreationally. The pharmacokinetics (PK) and central nervous system (CNS) effects of tetrahydrocannabinol (THC), the major psychoactive cannabinoid, are not well understood. The objective of this study was to develop a population PK model of inhaled THC, including sources of variability, and to conduct an exploratory analysis of potential exposure-response relationships.

A longitudinal study of cannabis use and risk for cognitive and functional decline among older adults with HIV.

Cannabis use is rapidly increasing among older adults in the United States, in part to treat symptoms of common health conditions (e.g., chronic pain, sleep problems).

Changes in Expression of DNA-Methyltransferase and Cannabinoid Receptor mRNAs in Blood Lymphocytes After Acute Cannabis Smoking.

Background: Cannabis use is a component risk factor for the manifestation of schizophrenia. The biological effects of cannabis include effects on epigenetic systems, immunological parameters, in addition to changes in cannabinoid receptors 1 and 2, that may be associated with this risk. However, there has been limited study of the effects of smoked cannabis on these biological effects in human peripheral blood cells.

The Relationship Between Plasma Tetrahydrocannabinol Levels and Intraocular Pressure in Healthy Adult Subjects.

Background: Δ9-tetrahydrocannabinol (THC) has been shown to decreased intraocular pressure (IOP). This project aims to define the relationship between plasma THC levels and IOP in healthy adult subjects.

Methods: Eleven healthy subjects received a single dose of inhaled cannabis that was self-administered in negative pressure rooms.

Driving Performance and Cannabis Users' Perception of Safety: A Randomized Clinical Trial.

Importance: Expanding cannabis medicalization and legalization increases the urgency to understand the factors associated with acute driving impairment.

Objective: To determine, in a large sample of regular cannabis users, the magnitude and time course of driving impairment produced by smoked cannabis of different Δ9-tetrahydrocannabinol (THC) content, the effects of use history, and concordance between perceived impairment and observed performance.

Design, Setting, And Participants: This double-blind, placebo-controlled parallel randomized clinical trial took place from February 2017 to June 2019 at the Center for Medicinal Cannabis Research, University of California San Diego.

Impact of HIV on Cognitive Performance in Professional Drivers.

Background: The intellectually demanding modern workplace is often dependent on good cognitive health, yet there is little understanding of how neurocognitive dysfunction related to HIV presents in employed individuals working in high-risk vocations such as driving. HIV-associated neurocognitive impairment is also associated with poorer long-term cognitive, health, and employment outcomes.

Setting: This study, set in Cape Town, South Africa, assessed the effects of HIV on neuropsychological test performance in employed male professional drivers.

Tablet-Based Cognitive Impairment Screening for Adults With HIV Seeking Clinical Care: Observational Study.

Background: Neurological complications including cognitive impairment persist among people with HIV on antiretrovirals; however, cognitive screening is not routinely conducted in HIV clinics.

Objective: Our objective for this study was 3-fold: (1) to determine the feasibility of implementing an iPad-based cognitive impairment screener among adults seeking HIV care, (2) to examine the psychometric properties of the tool, and (3) to examine predictors of cognitive impairment using the tool.

Methods: A convenience sample of participants completed Brain Baseline Assessment of Cognition and Everyday Functioning (BRACE), which included (1) Trail Making Test Part A, measuring psychomotor speed; (2) Trail Making Test Part B, measuring set-shifting; (3) Stroop Color, measuring processing speed; and (4) the Visual-Spatial Learning Test.

Daily Cannabis Use is Associated With Lower CNS Inflammation in People With HIV.

Objective: Recent cannabis exposure has been associated with lower rates of neurocognitive impairment in people with HIV (PWH). Cannabis's anti-inflammatory properties may underlie this relationship by reducing chronic neuroinflammation in PWH. This study examined relations between cannabis use and inflammatory biomarkers in cerebrospinal fluid (CSF) and plasma, and cognitive correlates of these biomarkers within a community-based sample of PWH.

Blood and Oral Fluid Cannabinoid Profiles of Frequent and Occasional Cannabis Smokers.

Increased prevalence of cannabis consumption and impaired driving are a growing public safety concern. Some states adopted per se driving laws, making it illegal to drive with more than a specified blood concentration of ∆9-tetrahydrocannabinol (THC) in a biological fluid (typically blood). Blood THC concentrations decrease significantly (∼90%) with delays in specimen collection, suggesting the use of alternative matrices, such as oral fluid (OF).

Paresthesia Predicts Increased Risk of Distal Neuropathic Pain in Older People with HIV-Associated Sensory Polyneuropathy.

Objective: Distal sensory polyneuropathy (DSP) is a disabling consequence of human immunodeficiency virus (HIV), leading to poor quality of life and more frequent falls in older age. Neuropathic pain and paresthesia are prevalent symptoms; however, there are currently no known curative treatments and the longitudinal course of pain in HIV-associated DSP is poorly characterized.

Methods: This was a prospective longitudinal study of 265 people with HIV (PWH) enrolled in the CNS HIV Antiretroviral Therapy Effects Research (CHARTER) study with baseline and 12-year follow-up evaluations.

The Current State of HIV and Aging: Findings Presented at the 10th International Workshop on HIV and Aging.

With increasing effectiveness of antiretroviral therapy, people with HIV (PWH) are living longer and the prevalence of older PWH continues to increase. Accordingly, PWH are experiencing an increased burden of age-related comorbidities. With this shifting demographics, clinicians and researchers face additional challenges in how to identify, address, and manage the complex intersections of HIV- and aging-related conditions.

Screening for HIV-Associated Neurocognitive Disorders: Sensitivity and Specificity.

HIV-associated neurocognitive disorder (HAND) remains prevalent among people living with HIV (PLWH), especially the mild forms, even those with well-controlled HIV. Recommendations from the literature suggest routine and regular screening for HAND to detect it early and manage it effectively and adjust treatments, if warranted, when present. However, screening for HAND is not routinely done, as there are no current guidelines on when to screen and which test or tests to use.

A Secondary Analysis from a Randomized Trial on the Effect of Plasma Tetrahydrocannabinol Levels on Pain Reduction in Painful Diabetic Peripheral Neuropathy.

This report examines the association between tetrahydrocannabinol (THC) plasma levels and pain response in a secondary analysis of data from a recent diabetic neuropathy study that demonstrated a dose-dependent reduction in spontaneous and elicited pain at specific time points. A randomized, double-blinded, placebo-controlled crossover study was conducted in sixteen patients with painful diabetic peripheral neuropathy. Subjects participated in four sessions, separated by 2 weeks, during each of which they were exposed to one of four conditions: placebo, or 1%, 4%, or 7% THC dose of cannabis.

Assessing HIV provider knowledge, screening practices, and training needs for HIV-associated neurocognitive disorders. A short report.

Management of HIV-associated neurocognitive disorders (HAND) is becoming increasingly important with HIV-positive people living normal life spans. We aimed to establish the level of HAND awareness among doctor and nurse occupational health practitioners, screening used to detect impairment, factors limiting screening for HAND, and training needs. One-hundred-and-five members of the nursing and physician professional societies for occupational health practitioners in South Africa and Occupational Health Departments at five South African universities responded to an email invitation to complete an online survey addressing demographics, HAND knowledge, screeners being used to screen for HAND and related training needs.