No Acute Effects of Cannabidiol on the Sleep-Wake Cycle of Healthy Subjects: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study

Cannabidiol (CBD) is a component of Cannabis sativa that has a broad spectrum of potential therapeutic effects in neuropsychiatric and other disorders. However, few studies have investigated the possible interference of CBD on the sleep-wake cycle. The aim of the present study was to evaluate the effect of a clinically anxiolytic dose of CBD on the sleep-wake cycle of healthy subjects in a crossover, double-blind design. Twenty-seven healthy volunteers that fulfilled the eligibility criteria were selected and allocated to receive either CBD (300 mg) or placebo in the first night in a double-blind randomized design (one volunteer withdrew from the study). In the second night, the same procedure was performed using the substance that had not been administered in the previous occasion. CBD or placebo were administered 30 min before the start of polysomnography recordings that lasted 8 h. Cognitive and subjective measures were performed immediately after polysomnography to assess possible residual effects of CBD. The drug did not induce any significant effect (p > 0.05). Different from anxiolytic and antidepressant drugs such as benzodiazepines and selective serotonin reuptake inhibitors, acute administration of an anxiolytic dose of CBD does not seem to interfere with the sleep cycle of healthy volunteers. The present findings support the proposal that CBD do not alter normal sleep architecture. Future studies should address the effects of CBD on the sleep-wake cycle of patient populations as well as in clinical trials with larger samples and chronic use of different doses of CBD. Such studies are desirable and opportune

Brazilian Medical Association guidelines for the diagnosis and differential diagnosis of panic disorder

Objective: To present the most relevant findings regarding the Brazilian Medical Association guidelines for the diagnosis and differential diagnosis of panic disorder. Methods: We used the methodology proposed by the Brazilian Medical Association for the Diretrizes Project. The MEDLINE (PubMed), Scopus, Web of Science, and LILACS online databases were queried for articles published from 1980 to 2012. Searchable questions were structured using the PICO format (acronym for “patient” [or population], “intervention” [or exposure], “comparison” [or control], and “outcome”). Results: We present data on clinical manifestations and implications of panic disorder and its association with depression, drug abuse, dependence and anxiety disorders. In addition, discussions were held on the main psychiatric and clinical differential diagnoses. Conclusions: The guidelines are proposed to serve as a reference for the general practitioner and specialist to assist in and facilitate the diagnosis of panic disorder

Can anxiety increase tremors in patients with Parkinson’s disease? An experimental model

<div><p>Abstract Background Among non-motor symptoms of Parkinson’s disease (PD), anxiety occurs in up to 67% of patients. Clinically, PD patients report worsening of tremors in anxiogenic situations. Objective The aim of this study was to evaluate the association between motor symptoms and anxiety in PD patients and compare their performances with those of healthy volunteers. Methods Fifteen volunteers with PD and 15 healthy volunteers without clinically significant psychiatric disorders were evaluated. Both groups were subjected to a simulated public speaking test (SPST). The following parameters were measured: visual analog mood scale (VAMS), items related to tremors of UPDRS, bradykinesia tests, blood pressure, and heart rate. Results Results of repeated measures ANOVA indicated a significant effect on group × phase interaction (F3.7,105.6 = 2.56; p = 0.046) for VAMS anxiety factor. Regarding tremors, ANOVA indicated significant differences in group × phase interaction (F4.5,121 = 2.88; p = 0.021) and between the groups (F1,27 = 45.88, p < 0.001), with differences in the anticipatory phase, performance, and post-speech, compared with those in the baseline. There were no significant differences between the groups with regard to other factors of VAMS, physiological measurements, and bradykinesia. Discussion Worsening of tremors occurred during SPST, particularly in phases with higher anxiety scores.</p></div