Our primary measure of recognition memory performance was d’, but Table 3 shows other performance measures for completeness, including the hit and false alarm rates used to calculate d’. Table 3 shows a measure of response bias (c = − 1/2 * [zH − zFA]), where negative values indicate a liberal bias to respond “old” and positive values indicate a conservative bias to respond “new”. Table 3 also shows response time (RT). Each of these performance measures were separately analyzed in a mixed-design analysis of variance (ANOVA) with session (pretest, posttest) as a within-subject factor, strain group (THC and THC + CBD) as a between-subject factor, and THC + metabolite levels as a covariate.
Time course of one trial during the study phase and the test phase
One of the 32 participants was excluded from analyses because their pretest blood levels exceeded mean + 3 standard deviation over all participants, when considering the combination of THC + metabolites level (sum of THC, THC-COOH and 11-OH-THC) and CBD level. Footnote 3 This reduced the THC + CBD strain group from 17 to 16 participants (see Table 1).
35 min after blood draw to assess peak cannabinoid levels) may have limited the observed effects of THC and CBD. On the other hand, we have found the effects of THC on verbal recall memory to be relatively persistent when international shopping list test (ISLT) performance was compared between 15 and 30 min after use versus 60–75 min after use (Bidwell et al. 2020). Third, given the nature of this observational pilot study we were not powered to include all relevant covariates or ethically able to match the groups on important characteristics such as cannabis use history, preferred form of cannabis (e.g. flower vs. concentrate), or preferred route of inhaled administration (e.g. bong, pipe, etc.). Furthermore, compared to the THC group, the THC + CBD group tended to be older (with age also ranging more widely), started regular cannabis use later, used less cannabis in the past month, and consumed significantly less THC in their assigned strain. Although the first three demographic trends were not significant, that may be attributable to the small sample size, so these factors could have contributed to group differences on memory. Despite these concerns, our strongest memory effects were shown in the THC group, which had the heaviest levels of use prior to the study sessions mitigating a concern that our findings are driven by tolerance effects in heavy users. Typically, heavier users are less likely to show acute decrements in memory performance (Ranganathan and D’Souza 2006; Schoeler and Bhattacharyya 2013).
17% THC, < 1% CBD; n = 11) or a + THC/+CBD strain (8% THC, 16% CBD; n = 12) that was acquired from a local dispensary. Participants used the assigned cannabis strain in accordance with their normal usage habits for 3 days, including a final use on the third day. Immediately after this final use, participants were transported to the lab by the research team for a detailed assessment of its effects on neuro- and bio- behavioral functions, including memory. Blood draws were collected before the three-day use period (i.e., baseline), immediately upon arrival at the lab (within 15 min of last cannabis use), and at the end of the two-hour assessment in order to verify effective strain assignment and cannabinoid exposure. Testing included the International Shopping List Task (ISLT) as a measure of verbal recall (Thompson et al. 2011). The ISLT consists of a 12-item shopping list that was read out loud to the participant three times in the same order. After 30 min, a delayed free recall test was given. Results suggested that recall performance was negatively correlated with THC blood levels for the THC-only strain (+THC/−CBD), but recall performance was not significantly correlated with THC blood levels for the CBD-containing strain (+THC/+CBD). These preliminary findings suggest that the strain type differentially affected recall and prompt further research into the impacts of naturalistic administration of legal market THC and CBD on memory function.
Multiple comparisons were assessed with Bonferroni post-hoc tests (with corresponding p-values reported as pbf) for all analyses.
Accuracy d’ according to blood biomarkers log (THC + metabolites) (a) and log (CBD) (b) during posttest, for the two strain groups: THC and THC + CBD. The black lines represent the correlation between accuracy and blood biomakers with R 2 reported
This is particularly exciting news as it is the first long-term study of this question.
Over the course of this year (and many years prior) Cannabidiol has been shown to be a potential therapy for:
Over the course of a 14-week treatment period, the subjects were randomly assigned either a daily dose of CBD oral solution based on body weight or a placebo. The doses were given in conjunction with each subject’s standard antiepileptic treatment.
Cannabis vs. Opioid-Based Pain Medication: Patient Self-Report
Authors: Kerstin Iffland and Franjo Grotenhermen; nova-Institut, Hürth, Germany
The bad: CBD might not be an effective treatment for anxiety itself.
In a test that involved giving volunteers chocolate milk to drink, this study sought the answer to a quirky question: Does CBD (or THC) affect how humans perceive “sweet taste.”
Authors: Vanessa P. Soares and Alline C. Campos
The average age for patients with anxiety was 34 years (range = 18–70 years) and age 36.5 years for patients with sleep disorders (range = 18–72 years). Most patients with an anxiety diagnosis were men (59.6%, 28/47), whereas more sleep-disordered patients were women (64.0%, 16/25). All 72 patients completed sleep and anxiety assessments at the onset of CBD treatment and at the first monthly follow-up. By the second monthly follow-up, 41 patients (56.9%) remained on CBD treatment and completed assessments; 27 patients (37.5%) remained on CBD treatment at the third monthly assessment.
Nearly all patients were given CBD 25 mg/d in capsule form. If anxiety complaints predominated, the dosing was every morning, after breakfast. If sleep complaints predominated, the dosing was every evening, after dinner. A handful of patients were given CBD 50 mg/d or 75 mg/d. One patient with a trauma history and schizoaffective disorder received a CBD dosage that was gradually increased to 175 mg/d.
Wholeness Center is a large mental health clinic in Fort Collins, CO, that focuses on integrative medicine and psychiatry. Practitioners from a range of disciplines (psychiatry, naturopathy, acupuncture, neurofeedback, yoga, etc) work together in a collaborative and cross-disciplinary environment. CBD had been widely incorporated into clinical care at Wholeness Center a few years before this study, on the basis of existing research and patient experience.
Side effects and tolerability of CBD treatment were assessed through spontaneous patient self-reports and were documented in case records. Any other spontaneous comments or complaints of patients were also documented in case records and included in this analysis.
Sleep and anxiety were the targets of this descriptive report. Sleep concerns were tracked at monthly visits using the Pittsburg Sleep Quality Index. Anxiety levels were monitored at monthly visits using the Hamilton Anxiety Rating Scale. Both scales are nonproprietary. The Hamilton Anxiety Rating Scale is a widely used and validated anxiety measure with 14 individual questions. It was first used in 1959 and covers a wide range of anxiety-related concerns. The score ranges from 0 to 56. A score under 17 indicates mild anxiety, and a score above 25 indicates severe anxiety. The Pittsburg Sleep Quality Index is a self-report measure that assesses the quality of sleep during a 1-month period. It consists of 19 items that have been found to be reliable and valid in the assessment of a range of sleep-related problems. Each item is rated 0 to 3 and yields a total score from 0 to 21. A higher number indicates more sleep-related concerns. A score of 5 or greater indicates a “poor sleeper.”
Many different cultures have used the Cannabis plant to treat a plethora of ailments. Practitioners in ancient China targeted malaria, menstrual symptoms, gout, and constipation. During medieval times, cannabis was used for pain, epilepsy, nausea, and vomiting, and in Western medicine it was commonly used as an analgesic.4,5 In the US, physicians prescribed Cannabis sativa for a multitude of illnesses until restrictions were put in place in the 1930s and then finally stopped using it in 1970 when the federal government listed marijuana as a Schedule I substance, claiming it an illegal substance with no medical value. California was the first state to go against the federal ban and legalize medical marijuana in 1996.6 As of June 2018, 9 states and Washington, DC, have legalized recreational marijuana, and 30 states and Washington, DC, allow for use of medical marijuana.7 The purpose of the present study is to describe the effects of CBD on anxiety and sleep among patients in a clinic presenting with anxiety or sleep as a primary concern.
Given the promising biochemical, physiologic, and preclinical data on CBD, a remarkable lack of randomized clinical trials and other formal clinical studies exist in the psychiatric arena. The present study describes a series of patients using CBD for treatment of anxiety or sleep disturbances in a clinical practice setting. Given the paucity of data in this area, clinical observations can be quite useful to advance the knowledge base and to offer questions for further investigation. This study aimed to determine whether CBD is helpful for improving sleep and/or anxiety in a clinical population. Given the novel nature of this treatment, our study also focused on tolerability and safety concerns. As a part of the evolving legal status of cannabis, our investigation also looked at patient acceptance.