Increased body sway in phobic patients exposed to images of spiders

Objective: The aim of the present study was to analyze the body sway response in specific phobia (SP) patients and healthy controls while viewing neutral, phobic, and disgusting images. Methods: The participants' heart rate (HR) and skin conductance were also recorded during the procedure. Nineteen patients with arachnophobia and 19 healthy volunteers matched by age, gender, and years of education underwent a postural control test on a stabilometric platform. Results: The platform recorded increased body sway in the SP group when exposed to spider images (SPI). The SP group presented increases in most parameters (SD, velocity, frequency, area, p ≤ 0.05) when viewing pictures of the SPI category. Psychometric measures of subjective anxiety (State-Trait Anxiety Inventory, STAI) and physiological states (HR; skin conductance responses; spontaneous fluctuations in skin conductance) showed increased anxiety (p ≤ 0.05) in the SP group compared to healthy volunteers. High anxiety levels were observed throughout the assessment, including the task of exposure to SPI (p ≤ 0.05). No significant effect or correlation was found between skin conductance and body sway measures (p > 0.05). Conclusions: The results of the postural control test suggest the occurrence of a defensive escape response in SP, in agreement with previous evidence.

Cannabidiol presents an inverted U-shaped dose-response curve in a simulated public speaking test

Objective: Cannabidiol (CBD), one of the non-psychotomimetic compounds of Cannabis sativa, causes anxiolytic-like effects in animals, with typical bell-shaped dose-response curves. No study, however, has investigated whether increasing doses of this drug would also cause similar curves in humans. The objective of this study was to compare the acute effects of different doses of CBD and placebo in healthy volunteers performing a simulated public speaking test (SPST), a well-tested anxiety-inducing method. Method: A total of 57 healthy male subjects were allocated to receive oral CBD at doses of 150 mg (n=15), 300 mg (n=15), 600 mg (n=12) or placebo (n=15) in a double-blind procedure. During the SPST, subjective ratings on the Visual Analogue Mood Scale (VAMS) and physiological measures (systolic and diastolic blood pressure, heart rate) were obtained at six different time points. Results: Compared to placebo, pretreatment with 300 mg of CBD significantly reduced anxiety during the speech. No significant differences in VAMS scores were observed between groups receiving CBD 150 mg, 600 mg and placebo. Conclusion: Our findings confirm the anxiolytic-like properties of CBD and are consonant with results of animal studies describing bell-shaped dose-response curves. Optimal therapeutic doses of CBD should be rigorously determined so that research findings can be adequately translated into clinical practice.

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

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.

Early interventions for the prevention of PTSD in adults: a systematic literature review

Abstract Background Secondary interventions are implemented within a short interval following the occurrence of traumatic events with the purpose of preventing the onset of PTSD. Objective Analyze the results of studies that assessed post-trauma interventions in adults aimed at preventing the onset of PTSD or symptoms related to PTSD. Methods We performed literature searches using the search expression [(Early intervention OR secondary prevention) AND (Post traumatic stress disorder OR PTSD)] for articles published until October 2016. Among the references found, 29 fulfilled the selection criteria established for the review. Data were divided and analyzed according to the type of intervention: pharmacological or psychological. Results Psychological measures used in the studies lack homogeneity regarding the type of intervention and the assessment of intervention outcomes. Pharmacological interventions were less frequent and findings require replication, together with an expansion in the types of substances investigated. In general, many of the studies reviewed suggest that both pharmacological and psychological interventions are effective in the prevention of PTSD. Discussion Future trials should be focused on determining the best interventions for the secondary prevention of PTSD. The combination of psychological and pharmacological interventions for post-trauma patients poses opportunities and challenges that remain unexplored.

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. .

Neuroimaging in specific phobia disorder: a systematic review of the literature / Neuroimagem do transtorno de fobia específica: uma revisão sistemática da literatura

OBJECTIVE: Specific phobia (SP) is characterized by irrational fear associated with avoidance of specific stimuli. In recent years, neuroimaging techniques have been used in an attempt to better understand the neurobiology of anxiety disorders. The objective of this study was to perform a systematic review of articles that used neuroimaging techniques to study SP. METHOD:A literature search was conducted through electronic databases, using the keywords: imaging, neuroimaging, PET, spectroscopy, functional magnetic resonance, structural magnetic resonance, SPECT, MRI, DTI, and tractography, combined with simple phobia and specific phobia. One-hundred fifteen articles were found, of which 38 were selected for the present review. From these, 24 used fMRI, 11 used PET, 1 used SPECT, 2 used structural MRI, and none used spectroscopy. RESULT: The search showed that studies in this area were published recently and that the neuroanatomic substrate of SP has not yet been consolidated. CONCLUSION: In spite of methodological differences among studies, results converge to a greater activation in the insula, anterior cingulate cortex, amygdala, and prefrontal and orbitofrontal cortex of patients exposed to phobia-related situations compared to controls. These findings support the hypotheses of the hyperactivation of a neuroanatomic structural network involved in SP.

A Fobia Específica (SP do inglês) é caracterizada por medos irracionais associados à evitação de estímulos específicos. Nos últimos anos, técnicas de neuroimagem vêm sendo empregadas na tentativa de melhor compreender a neurobiologia dos transtornos de ansiedade. O objetivo do presente estudo é realizar uma revisão sistemática dos artigos que utilizaram neuroimagem para estudar a SP. A busca na literatura foi realizada por intermédio de indexadores eletrônicos, utilizando-se as palavras-chave: imaging, neuroimaging, PET, spectroscopy, functional magnetic ressonance, structural magnetic ressonance, SPECT, MRI, DTI e tractography, cruzadas individualmente com os termos simple phobia e specific phobia. Foram encontrados 115 artigos, sendo 38 deles selecionados para a presente revisão. Desses, 24 usaram fMRI, 11 usaram PET, 1 usou SPECT, 2 usaram MRI estrutural e nenhum artigo de espectroscopia. Verifica-se que os estudos na área foram publicados recentemente e que, até o momento, o substrato neuroanatômico deste transtorno não está consolidado. Apesar das diferenças metodológicas entre os estudos, os resultados convergem para maior ativação na ínsula, cíngulo anterior, amídala e córtex préfrontal e orbitofrontal dos pacientes expostos a situações phobia related quando comparados aos controles. Esses achados reforçam hipóteses a respeito da hiperativação de uma determinada rede de estruturas neuroanatômicas envolvidas no transtorno de SP.