Subjective Measures Of Anxiety Research Articles

Design of Pediatric Outpatient Procedure Environments: A Pilot Study to Understand the Perceptions of Patients and Their Parents.

To understand parent and child perception of spaces experienced during outpatient procedures and to measure their anxiety in these spaces. Same-day procedures are becoming prevalent among children in the United States. While studies conducted in different types of healthcare settings show that the physical environment influences healthcare experiences of patients, there is a lack of research on patient and family perceptions of the physical environment of the outpatient centers where such procedures are conducted. This study used ecological momentary assessment to collect patient experience and anxiety data at different points during the patient's journey through an ambulatory surgical center where pediatric gastrointestinal (GI) procedures were performed. Objective and subjective measures of anxiety were collected. A Qualtrics survey asked participants' perceptions about four spaces-waiting, preprocedure, procedure, and recovery. Child participants reported liking murals, double chairs, patient beds, wall color, and access to a television. They disliked medical equipment and lack of child-friendly furniture. Most parents liked the murals, access to a television, and nature photos, while disliking the lack of privacy, lack of toys in waiting areas, and lack of child-friendly furniture. On average, both children and parents experienced the highest anxiety levels before and during the procedure and the lowest during recovery. Between the four spaces, no significant differences were observed in the heart rate variability and skin conductance responses for both groups. Despite the outpatient nature of the procedures, participants experienced anxiety before the GI procedure. Comfortable design features that provide distractions are preferred by children and their parents.

Physiological and Subjective Measures of Anxiety with Repeated Exposure to Virtual Construction Sites at Different Heights

BackgroundOccupational workers at altitudes are more prone to falls, leading to catastrophic outcomes. Acrophobia, height-related anxiety, and affected executive functions lead to postural instabilities, causing falls. This study investigated the effects of repeated virtual height exposure and training on cognitive processing and height-related anxiety. MethodsTwenty-eight healthy volunteers (age 20.48 ± 1.26 years; mass 69.52 ± 13.78 kg) were recruited and tested in seven virtual environments (VE) [ground (G), 2-story altitude (A1), 2-story edge (E1), 4-story altitude (A2), 4-story edge (E2), 6-story altitude (A3), and 6-story edge (E3)] over three days. At each VE, participants identified occupational hazards present in the VE and completed an Attitude Towards Heights Questionnaire (ATHQ) and a modified State-Trait Anxiety Inventory Questionnaire (mSTAIQ). The number of hazards identified and the ATHQ and mSTAIQ scores were analyzed using a 7 (VE; G, A1, A2, A3, E1, E2, E3) x 3 (DAY; DAY 1, DAY 2, DAY 3) factorial repeated measures analysis of variance. ResultsThe participants identified the lowest number of hazards at A3 and E3 VEs and on DAY 1 compared to other VEs and DAYs. ATHQ scores were lowest at G, A1, and E1 VEs. ConclusionCognitive processing is negatively affected by virtual altitudes, while it improves with short-term training. The features of virtual reality, such as higher involvement, engagement, and reliability, make it a better training tool to be considered in ergonomic settings. The findings of this study will provide insights into cognitive dual-tasking at altitude and its challenges, which will aid in minimizing occupational falls.

The relationship between patient empowerment and related constructs, affective symptoms and quality of life in patients with type 2 diabetes: a systematic review and meta-analysis

The aim of this systematic review is to assess the relationship between patient empowerment and other empowerment-related constructs, and affective symptoms and quality of life in patients with type 2 diabetes. A systematic review of the literature was conducted, according to the PRISMA guidelines. Studies addressing adult patients with type 2 diabetes and reporting the association between empowerment-related constructs and subjective measures of anxiety, depression and distress, as well as self-reported quality of life were included. The following electronic databases were consulted from inception to July 2022: Medline, Embase, PsycINFO, and Cochrane Library. The methodological quality of the included studies was analyzed using validated tools adapted to each study design. Meta-analyses of correlations were performed using an inverse variance restricted maximum likelihood random-effects. The initial search yielded 2463 references and seventy-one studies were finally included. We found a weak-to-moderate inverse association between patient empowerment-related constructs and both anxiety (r = -0.22) and depression (r = -0.29). Moreover, empowerment-related constructs were moderately negatively correlated with distress (r = -0.31) and moderately positively correlated with general quality of life (r = 0.32). Small associations between empowerment-related constructs and both mental (r = 0.23) and physical quality of life (r = 0.13) were also reported. This evidence is mostly from cross-sectional studies. High-quality prospective studies are needed not only to better understand the role of patient empowerment but to assess causal associations. The results of the study highlight the importance of patient empowerment and other empowerment-related constructs such as self-efficacy or perceived control in diabetes care. Thus, they should be considered in the design, development and implementation of effective interventions and policies aimed at improving psychosocial outcomes in patients with type 2 diabetes. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020192429, identifier CRD42020192429.

Salivary Biomarkers Associated with Psychological Alterations in Patients with Diabetes: A Systematic Review.

The care of individuals with diabetes needs a holistic perspective, taking into account both the physical disease and the mental health problems that may be associated. Different studies show a higher prevalence of depression or anxiety issues in diabetes patients than in the general population, which is why diabetes can be considered one of the chronic diseases in which psychological care is crucial to maintain quality of life. The objective of this review is to examine the published articles that relate the bidirectional associations between objective and subjective measures of anxiety, depressive symptomatology, stress, sleep quality, and salivary biomarkers in patients with diabetes. For this, a search was carried out in the electronic databases PubMed, Cochrane, and SCOPUS using the keywords “diabetes”, “saliva”, “sleep”, “anxiety”, “depression”, and “stress” for works published up until May 2022 and limited to the English and Spanish languages. The sample comprised 14 articles, 5 of which analysed the associations between depressive symptomatology and salivary biomarkers in people with diabetes. Among the salivary biomarkers most frequently used to evaluate psychological alterations in persons with diabetes are cortisol and melatonin. Thus, significant changes in the levels of these biomarkers were observed in most studies. Four out of five studies reported a statistically significant relationship between increased salivary cortisol in the evening/midnight or the cortisol awakening response and depressive symptoms. In contrast, lower cortisol levels upon waking in the morning were observed when there was no depression or anxiety. Regarding the association between salivary cortisol values and sleep quality in patients with diabetes, lower morning cortisol values related to prolonged nighttime sleep were common in the analysed studies. Low melatonin concentrations showed a negative correlation with sleep quality. As it is an easy-to-apply and non-invasive method, the measurement of salivary biomarkers can be very useful for predicting psychological alterations in patients with diabetes. Further scientific studies are required to determine the sensitivity of these biological substances acting as biomarkers for detecting sleep disorders and psychological alterations.

Targeted Memory Reactivation During REM Sleep in Patients With Social Anxiety Disorder.

BackgroundSocial anxiety disorder (SAD) is characterized by a significant amount of fear when confronted to social situations. Exposure therapy, which is based on fear extinction, does not often lead to full remission. Here, based on evidence showing that rapid eye movement (REM) sleep promotes the consolidation of extinction memory, we used targeted memory reactivation (TMR) during REM sleep to enhance extinction learning in SAD.MethodsForty-eight subjects with SAD were randomly assigned to two groups: control or TMR group. All patients had two successive exposure therapy sessions in a virtual reality (VR) environment, where they were asked to give a public talk in front of a virtual jury. At the end of each session, and only in the TMR group (N = 24), a sound was paired to the positive feedback phase of therapy (i.e., approval of their performance), which represented the memory to be strengthened during REM sleep. All participants slept at home with a wearable headband device which automatically identified sleep stages and administered the sound during REM sleep. Participants' anxiety level was assessed using measures of parasympathetic (root mean square of successive differences between normal heartbeats, RMSSD) and sympathetic (non-specific skin conductance responses, ns-SCRs) activity, and subjective measures (Subjective Units of Distress Scale, SUDS), during the preparation phase of their talks before (T1) and after (T2) one full-night's sleep and after 1 week at home (T3). Participants also filled in a dream diary.ResultsWe observed an effect of time on subjective measures of anxiety (SUDS). We did not find any difference in the anxiety levels of the two groups after 1 week of TMR at home. Importantly, the longer the total duration of REM sleep and the more stimulations the TMR group had at home, the less anxious (increased RMSSD) these participants were. Finally, fear in dreams correlated positively with ns-SCRs and SUDS at T3 in the TMR group.ConclusionTMR during REM sleep did not significantly modulate the beneficial effect of therapy on subjective anxiety. Yet, our results support that REM sleep can contribute to extinction processes and substantiate strong links between emotions in dreams and waking stress levels in these patients.

Validation of a virtual environment for sexual aversion

This study focused on sexual aversion (SA) – namely the experience of fear, disgust, and avoidance when exposed to sexual contexts or cues – and aimed to validate a virtual environment's ability to progressively trigger the typical emotional responses of SA. Thirty-nine participants (16 low-SA and 23 high-SA individuals) were immersed in a virtual room and then successively exposed to six scenarios in which a synthetic character showed erotic behaviors of increasing sexual intensity. Throughout immersion, subjective measures of anxiety and disgust (Subjective Units of Discomfort Scale; SUDS), skin conductance, heart rate, cardiac output, and eye movements were recorded. The changes in SUDS and physiological variables were examined through repeated measures analyses of variance. SUDS scores significantly increased as the levels of exposure progressed among the high-SA participants, who also reported significantly more anxiety and disgust than the low-SA group. Significant large time effects were found for cardiac output and eye fixation (on face, chest, and genitals), but no significant group*time interactions were found for physiological variables. Results show that this virtual environment may be a promising tool for research and practice, and its efficacy as part of a virtual reality exposure-based treatment for SA should be tested.

Self-Reported Sleep Quality Across Age Modulates Resting-State Functional Connectivity in Limbic and Fronto-Temporo-Parietal Networks: An Exploratory Cross-Sectional fMRI Study.

Sleep problems are increasingly present in the general population at any age, and they are frequently concurrent with—or predictive of—memory disturbances, anxiety, and depression. In this exploratory cross-sectional study, 54 healthy participants recruited in Naples (Italy; 23 females; mean age = 37.1 years, range = 20–68) completed the Pittsburgh Sleep Quality Index (PSQI) and a neurocognitive assessment concerning both verbal and visuospatial working memory as well as subjective measures of anxiety and depression. Then, 3T fMRI images with structural and resting-state functional sequences were acquired. A whole-brain seed-to-seed functional connectivity (FC) analysis was conducted by contrasting good (PSQI score <5) vs. bad (PSQI score ≥5) sleepers. Results highlighted FC differences in limbic and fronto-temporo-parietal brain areas. Also, bad sleepers showed an anxious/depressive behavioural phenotype and performed worse than good sleepers at visuospatial working-memory tasks. These findings may help to reveal the effects of sleep quality on daily-life cognitive functioning and further elucidate pathophysiological mechanisms of sleep disorders.

Attentional Biases in Adults Who Stutter before and following Social Threat Induction

Purpose: We know that adults who stutter report higher levels of social anxiety [Craig and Tran: J Fluency Disord 2014;40:35–43; Iverach et al.: J Anxiety Disord 2009;23(7):928–34]. What is not clear is whether adults who stutter develop maladaptive attentional shifts, similar to what is observed in socially anxious individuals, in response to social anxiety. The purpose of this study was to investigate the attentional biases in adults who stutter compared to adults who do not stutter before and after social evaluative threat induction and determine whether responses are associated with objective and subjective measures of anxiety. Method: Twelve adults who stutter and 14 matched adults who do not stutter performed a modified response time paradigm, the dot-probe task, where they responded to a probe appearing behind one of two faces, one emotional (positive or negative) and one neutral. Participant’s reaction times were measured before and after a social threat induction task. Skin conductance levels were used as an index of induced stress. Self-reports of trait and social anxiety were used as subjective measures of anxiety. Results: Adults who stutter compared to controls exhibited an attentional bias towards negative facial expressions following a social evaluative threat induction. This effect remained when covarying for levels of trait and social anxiety. Before social evaluative threat induction, visual inspection of the data showed that adults who stutter compared to adults who do not stutter avoided positive facial expressions as they attended more to the negative facial expressions; however, these differences were not significant. Discussion: This study provides evidence for a maladaptive attentional behavior in adults who stutter when undergoing feelings of social evaluative threat. Results provide rationale for research aimed at assessing the use of attention restructuring in highly anxious adults who stutter.

The effects of a music intervention during port catheter placement on anxiety and stress

Studies have shown that perioperative music interventions can reduce patients’ anxiety levels. However, in small operations like port catheter surgery evidence is sparse. The present single-blinded, randomised controlled two-armed study included 84 female patients undergoing port catheter placement who were randomly assigned to either listening to music during surgery vs. no music intervention. The medical staff was blind to group allocation. On the day of the surgery anxiety and stress levels were evaluated using subjective (STAI questionnaire, visual analogue scales) and objective (vital parameters, salivary cortisol) parameters at different time points (before the surgery, at the end of the surgery and 1 h post-surgery). The music group showed significant reductions of systolic blood pressure (from 136.5 mmHg ± 26.1 to 123.3 mmHg ± 22.0, p = .002) and heart rate (from 75.6 bpm ± 12.3 to 73.1 bpm ± 12.2, p = .035) from beginning of the surgery to skin suture, whereas the control group did not. No significant effects of the music intervention on subjective anxiety measures or salivary cortisol were revealed. In sum, the study demonstrates that a music intervention during port catheter placement positively influences physiological anxiety levels, whereas no effects were revealed for subjective anxiety and salivary cortisol. Thus, music can be considered as a low cost addition in clinical routine in order to reduce patients’ heart rate and blood pressure. Future studies are encouraged to further explore the differential effects of intraoperative music interventions on physiological, endocrinological and subjective anxiety levels.

Attention avoidance of the threat conditioned stimulus during extinction increases physiological arousal generalisation and retention

Exposure therapy is a key component of efficacious treatment for anxiety. Biases in the allocation of attention towards versus away from threat assessed prior to exposure-based treatments such as cognitive-behavioural therapy differentially predict treatment outcomes. However, it is unclear whether monitoring versus avoiding threat stimuli influences learning during exposure. Extinction paradigms are the experimental analogue of exposure therapy. Therefore, manipulating attention towards versus away from threat during extinction trials may shed light on the role of attention during exposure therapy. This study utilised a Pavlovian fear conditioning and extinction paradigm to examine whether directing attention towards versus away from the threat conditioned stimulus (CS+) related to differences in extinction, as indexed by skin conductance responses (SCR), CS evaluations and subjective measures of anxiety. Following a fear conditioning phase in which a dog image (CS+) was paired with an aversive tone unconditioned stimulus (US) and another dog image (CS-) was presented alone, 57 participants were randomly assigned to one of three conditions during extinction in which both CSs were presented alone: monitor the CS+ (N = 19), avoid the CS+ and attend to another stimulus (N = 18), no attention manipulation control (N = 20). Eye movements were monitored for visual adherence to assigned location using horizontal electro-oculogram. In the context of the acquisition of differential conditioning and visual adherence during extinction, both active groups exhibited larger SCRs to the CS + relative to the CS- during the first extinction block compared to the control group, and the avoid group exhibited significantly larger SCRs on CS+ and CS- trials throughout the extinction phase compared to the other groups. The avoid group also exhibited less decline in SCRs to the CS+ during the extinction retest phase relative to the control group. No significant group differences were observed in between-phase CS evaluations and subjective anxiety ratings. Avoidance of threat conditioned stimuli may impair extinction learning and increase physiological arousal generalisation to safe stimuli.

P.2.006 - Belief about group allocation predicts placebo response in the 7.5% carbon dioxide inhalational model of anxiety

Placebo-controlled trials are the current gold-standard measure of efficacy of novel anxiolytic treatments. However, placebo treatment can also produce clinical improvement, which has important implications for the design and evaluation of clinical trials. The placebo response is thought to result from interactions between prior expectations of treatment and learning [1]. A participant’s ‘belief’ in whether they were allocated to active medication or placebo treatment is likely informed by their expectations and experience of a clinical trial. We investigated whether belief correlates with the magnitude of the anxiolytic response to placebo in the 7.5% CO2 experimental medicine model of anxiety. We pooled data from healthy volunteers randomised to the placebo arms of 2-week double-blind trials (n = 51, 27 males, mean age 22.9 years). On day 14, participants completed two 20-minute inhalations of normal air and air enriched with 7.5% CO2 (CO2 challenge) in randomised order. We recorded heart rate, blood pressure and subjective measures of anxiety at baseline and following each inhalation. Following testing, participants recorded whether they thought they were taking drug or placebo, and their confidence in this decision, on two visual analogue scales. These measures were combined to produce a single interaction term we called ‘belief’. Belief ranged from 0 to 1, where 0 equated to the participant fully believing they were receiving placebo and 1 represented full belief they were receiving medication. We assessed response to CO2 challenge through mixed model ANOVAs for each outcome measure with time as the within-subject factor. To assess whether ‘belief’ could predict response to CO2 challenge, we performed linear regression analyses. Our predictor variables of belief and order of inhalation were regressed with outcome variables we hypothesised would be influenced by belief. Mixed model ANOVAs showed that CO2 challenge significantly increased blood pressure and heart rate (F’s > 4.10, p 35.1, p Participants who believed they were receiving active medication experienced less subjective anxiety during CO2 challenge following 14 days of treatment. This is consistent with other studies that have shown expectation of anxiety relief can lead to anxiolysis [2,3]. Interestingly, there was no effect of belief on physiological measures of anxiety. More studies are needed to further understand the link between participants’ beliefs about drug group allocation and response in experimental medicine studies and clinical trials.

Inverted U-Shaped Dose-Response Curve of the Anxiolytic Effect of Cannabidiol during Public Speaking in Real Life.

The purpose of this study was to investigate whether the anxiolytic effect of cannabidiol (CBD) in humans follows the same pattern of an inverted U-shaped dose-effect curve observed in many animal studies. Sixty healthy subjects of both sexes aged between 18 and 35 years were randomly assigned to five groups that received placebo, clonazepam (1 mg), and CBD (100, 300, and 900 mg). The subjects were underwent a test of public speaking in a real situation (TPSRS) where each subject had to speak in front of a group formed by the remaining participants. Each subject completed the anxiety and sedation factors of the Visual Analog Mood Scale and had their blood pressure and heart rate recorded. These measures were obtained in five experimental sessions with 12 volunteers each. Each session had four steps at the following times (minutes) after administration of the drug/placebo, as time 0: -5 (baseline), 80 (pre-test), 153 (speech), and 216 (post-speech). Repeated-measures analyses of variance showed that the TPSRS increased the subjective measures of anxiety, heart rate, and blood pressure. Student-Newman-Keuls test comparisons among the groups in each phase showed significant attenuation in anxiety scores relative to the placebo group in the group treated with clonazepam during the speech phase, and in the clonazepam and CBD 300 mg groups in the post-speech phase. Clonazepam was more sedative than CBD 300 and 900 mg and induced a smaller increase in systolic and diastolic blood pressure than CBD 300 mg. The results confirmed that the acute administration of CBD induced anxiolytic effects with a dose-dependent inverted U-shaped curve in healthy subjects, since the subjective anxiety measures were reduced with CBD 300 mg, but not with CBD 100 and 900 mg, in the post-speech phase.

The Effects of Magnesium Supplementation on Subjective Anxiety and Stress-A Systematic Review.

Background: Anxiety related conditions are the most common affective disorders present in the general population with a lifetime prevalence of over 15%. Magnesium (Mg) status is associated with subjective anxiety, leading to the proposition that Mg supplementation may attenuate anxiety symptoms. This systematic review examines the available evidence for the efficacy of Mg supplementation in the alleviation of subjective measures of anxiety and stress. Methods: A systematic search of interventions with Mg alone or in combination (up to 5 additional ingredients) was performed in May 2016. Ovid Medline, PsychInfo, Embase, CINAHL and Cochrane databases were searched using equivalent search terms. A grey literature review of relevant sources was also undertaken. Results: 18 studies were included in the review. All reviewed studies recruited samples based upon an existing vulnerability to anxiety: mildly anxious, premenstrual syndrome (PMS), postpartum status, and hypertension. Four/eight studies in anxious samples, four/seven studies in PMS samples, and one/two studies in hypertensive samples reported positive effects of Mg on subjective anxiety outcomes. Mg had no effect on postpartum anxiety. No study administered a validated measure of subjective stress as an outcome. Conclusions: Existing evidence is suggestive of a beneficial effect of Mg on subjective anxiety in anxiety vulnerable samples. However, the quality of the existing evidence is poor. Well-designed randomised controlled trials are required to further confirm the efficacy of Mg supplementation.

Caregivers of patients with amyotrophic lateral sclerosis: investigating quality of life, caregiver burden, service engagement, and patient survival.

Few studies in amyotrophic lateral sclerosis (ALS) have profiled disease-specific features of the condition in conjunction with assessment of caregivers' burden, distress, quality of life, and investigated patient survival. Eighty-four ALS patients and their primary caregivers were enrolled. Patients completed ALS-specific measures of physical and cognitive function, while caregivers completed measures of anxiety, depression, caregiver burden, and quality of life. Patient-caregiver dyads were interviewed about their health-service utilisation. Survival data were obtained through the Irish register for ALS. Participants were dichotomised into low/high groups according to the severity of self-reported caregiver burden, based on statistically derived cut-off scores. High-burdened caregivers (n=43) did not significantly differ from low-burdened caregivers (n=41) with respect to disease-specific characteristics, i.e., ALSFRS-R, bulbar- or spinal-onset ALS, disease duration, or survival data. However, significant differences were reported on subjective measures of anxiety (p<0.000), depression (p<0.001), distress (p<0.000), and quality of life (p<0.000). These data demonstrate the limited impact of ALS patient-related variables, i.e., ALSFRS-R and onset, on caregiver burden in ALS, and identify the importance of the psychological composition of caregivers. This study suggests that the subjective experience of individual caregivers is an important factor influencing the severity of experienced caregiver burden.

Feasibility of Training Athletes for High-Pressure Situations Using Virtual Reality

Virtual reality (VR) has been successfully applied to a broad range of training domains; however, to date there is little research investigating its benefits for sport psychology training. We hypothesized that using high-fidelity VR systems to display realistic 3D sport environments could trigger anxiety, allowing resilience-training systems to prepare athletes for real-world, highpressure situations. In this work we investigated the feasibility and usefulness of using VR for sport psychology training. We developed a virtual soccer goalkeeping application for the Virginia Tech Visionarium VisCube (a CAVE-like display system), in which users defend against simulated penalty kicks using their own bodies. Using the application, we ran a controlled, within-subjects experiment with three independent variables: known anxiety triggers, field of regard, and simulation fidelity. The results demonstrate that a VR sport-oriented system can induce increased anxiety (physiological and subjective measures) compared to a baseline condition. There were a number of main effects and interaction effects for all three independent variables in terms of the subjective measures of anxiety. Both known anxiety triggers and simulation fidelity had a direct relationship to anxiety, while field of regard had an inverse relationship. Overall, the results demonstrate great potential for VR sport psychology training systems; however, further research is needed to determine if training in a VR environment can lead to long-term reduction in sport-induced anxiety.

Physiological reactivity to phobic stimuli in people with fear of flying

Objective The nature of the relationship between physiological and subjective responses in phobic subjects remains unclear. Phobics have been thought to be characterized by a heightened physiological response (physiological perspective) or by a heightened perception of a normal physiological response (psychological perspective). Method In this study, we examined subjective measures of anxiety, heart rate (HR), and cardiac autonomic responses to flight-related stimuli in 127 people who applied for fear-of-flying therapy at a specialized treatment center and in 36 controls without aviophobia. Results In keeping with the psychological perspective, we found a large increase in subjective distress ( η 2=.43) during exposure to flight-related stimuli in the phobics and no change in subjective distress in the controls, whereas the physiological responses of both groups were indiscriminate. However, in keeping with the physiological perspective, we found that, within the group of phobics, increases in subjective fear during exposure were moderately strong coupled to HR ( r=.208, P=.022) and cardiac vagal ( r=.199, P=.028) reactivity. In contrast to predictions by the psychological perspective, anxiety sensitivity did not modulate this coupling. Conclusion We conclude that subjective fear responses and autonomic responses are only loosely coupled during mildly threatening exposure to flight-related stimuli. More ecologically valid exposure to phobic stimuli may be needed to test the predictions from the physiological and psychological perspectives.

AN EFFECT OF POSTURE ON ANTICIPATORY ANXIETY

This study investigated the effects of body posture on state anxiety and psychological stress. Twenty normal adults performed a demanding mental arithmetic task in both standing and supine conditions, with subjective measures of anxiety and stress obtained before, immediately, and 10 min after the task. Participants were found to experience anticipatory anxiety when standing, although not when supine. The mechanism underlying this effect remains to be determined, although it could involve a postural difference in baroreceptor load.

Protein-source tryptophan as an efficacious treatment for social anxiety disorder: a pilot studyThis article is one of a selection of papers published in this special issue (part 1 of 2) on the Safety and Efficacy of Natural Health Products.

Until recently, intact protein that is rich in tryptophan was not seen as an alternative to pharmaceutical-grade tryptophan because protein also contains large neutral amino acids (LNAAs) that compete for transport sites across the blood-brain barrier. Recent evidence indicates that when deoiled gourd seed (a rich source of tryptophan with approximately 22 mg/g protein) is combined with glucose (a carbohydrate that reduces serum levels of competing LNAAs) a clinical effect similar to that of pharmaceutical-grade tryptophan is achieved. Objective and subjective measures of anxiety in those suffering from social phobia (also known as social anxiety disorder) were employed to measure changes in anxiety in response to a stimulus as part of a double-blind, placebo-controlled, crossover study with a wash-out period of 1 week between study sessions. Subjects were randomly assigned to start with either (i) protein-source tryptophan (deoiled gourd seed) in combination with carbohydrate or (ii) carbohydrate alone. One week after the initial session, subjects returned for a follow-up session and received the opposite treatment of that received at the first session. All 7 subjects who began the study completed the 2-week protocol. Protein-source tryptophan with carbohydrate, but not carbohydrate alone, resulted in significant improvement on an objective measure of anxiety. Protein-source tryptophan combined with a high glycemic carbohydrate is a potential anxiolytic to those suffering from social phobia.

Attention focusing versus distraction during exposure in dental phobia

A survey of the discrepant findings regarding the effects of attention focusing and distraction on exposure suggested that subjective measures of anxiety and avoidance respond better to the latter condition, and heart rate (HR) reaction responds to the former. To test this hypothesis, 63 dental phobics were recruited who had not visited a dentist for a mean of 6.6 (1.5–25) years. Participants received a 1-h exposure session with either attention focusing or distraction. Subjective anxiety and HR to phobia-related pictures were assessed before and after the treatment session and again after 1 week. Avoidance was recorded in terms of adherence to the dental treatment schedule in the following 6 months. Contrary to expectation, state anxiety showed a greater decrease in the attention focusing than the distraction condition after 1 week. Both treatment conditions were similarly effective with regard to HR and avoidance. HR habituated in both groups after exposure and 73% of followed-up patients adhered to the dental treatment schedule. Comparison of the present with previous results suggests that the differences between attentional conditions tend to be more pronounced during shorter exposure sessions than were employed in the present study.

Carbon dioxide provocation of anxiety and respiratory response in bipolar disorder

Background Frequent bipolar/panic comorbidity implies bipolar individuals may experience CO 2-provoked anxiety and changes in respiratory patterns similar to those experienced by individuals with panic disorder. Methods 16 euthymic bipolar individuals breathed air and air combined with 5% CO 2 for 15 min each. Respiratory and subjective anxiety measures were collected. Results On CO 2 subjects were more anxious and breathed more deeply and rapidly than with air; the degree of increase in anxiety attributable to CO 2 was directly correlated with the degree of increase in minute ventilation. Five individuals were assessed as having a panic attack. Panic response to CO 2 was predicted by the degree of anxiety experienced with air alone. Conclusions Comparison with the results of similar panic studies shows bipolar disorder is associated with enhanced respiratory response to CO 2. Hypersensitivity to CO 2 among bipolar individuals suggests a possible pathological mechanism common to both bipolar and panic disorders. These preliminary data support the expanded application of CO 2 challenges in bipolar subjects.