First experience of evaluation of the impact of high-matrix size reconstruction in image quality in arterial CT runoff studies of the lower extremities.

OBJECTIVES: To determine whether image reconstruction with a higher matrix size improves image quality for lower extremity CTA studies. METHODS: Raw data from 50 consecutive lower extremity CTA studies acquired on two MDCT scanners (SOMATOM Flash, Force) in patients evaluated for peripheral arterial disease (PAD) were retrospectively collected and reconstructed with standard (512 × 512) and higher resolution (768 × 768, 1024 × 1024) matrix sizes. Five blinded readers reviewed representative transverse images in randomized order (150 total). Readers graded image quality (0 (worst)-100 (best)) for vascular wall definition, image noise, and confidence in stenosis grading. Ten patients' stenosis scores on CTA images were compared to invasive angiography. Scores were compared using mixed effects linear regression. RESULTS: Reconstructions with 1024 × 1024 matrix were ranked significantly better for wall definition (mean score 72, 95% CI = 61-84), noise (74, CI = 59-88), and confidence (70, CI = 59-80) compared to 512 × 512 (wall = 65, CI = 53 × 77; noise = 67, CI = 52 × 81; confidence = 62, CI = 52 × 73; p = 0.003, p = 0.01, and p = 0.004, respectively). Compared to 512 × 512, the 768 × 768 and 1024 × 1024 matrix improved image quality in the tibial arteries (wall = 51 vs 57 and 59, p < 0.05; noise = 65 vs 69 and 68, p = 0.06; confidence = 48 vs 57 and 55, p < 0.05) to a greater degree than the femoral-popliteal arteries (wall = 78 vs 78 and 85; noise = 81 vs 81 and 84; confidence = 76 vs 77 and 81, all p > 0.05), though for the 10 patients with angiography accuracy of stenosis grading was not significantly different. Inter-reader agreement was moderate (rho = 0.5). CONCLUSION: Higher matrix reconstructions of 768 × 768 and 1024 × 1024 improved image quality and may enable more confident assessment of PAD. CLINICAL RELEVANCE STATEMENT: Higher matrix reconstructions of the vessels in the lower extremities can improve perceived image quality and reader confidence in making diagnostic decisions based on CTA imaging. KEY POINTS: • Higher than standard matrix sizes improve perceived image quality of the arteries in the lower extremities. • Image noise is not perceived as increased even at a matrix size of 1024 × 1024 pixels. • Gains from higher matrix reconstructions are higher in smaller, more distal tibial and peroneal vessels than in femoropopliteal vessels.

A randomized trial of one versus three hyperbaric oxygen sessions for acute carbon monoxide poisoning.

Introduction: Hyperbaric oxygen (HBO2) improves outcome in patients with acute carbon monoxide (CO) poisoning, but optimal dose/timing are unknown. In this double-blind, sham-controlled randomized trial, we compared neuropsychological sequelae at six weeks and six months in patients receiving three HBO2 sessions or one HBO2 session and two sham chamber sessions after acute CO poisoning. Methods: After completing one HBO2 session (3.0 ATA, 60 minutes, 2.0 ATA, 65 minutes), CO-poisoned patients were randomized (1:1): two sham chamber sessions (1 ATA air, 120 minutes) or two additional HBO2sessions (2.0 ATA, 90 minutes at pressure, 120 minutes in chamber) completed within 24 hours. Eligible patients were >24 hours from accidental poisoning, English-speaking, and not intubated. We planned 150 participants. Results: The study was stopped early for enrollment futility. From 2006 to 2016, we screened 395 patients: 136 were deemed eligible to participate, and 75 signed informed consent. Two were later withdrawn for past brain injury/PTSD (one sham, one HBO2), and one for performance validity (sham). Of the 72 analyzed, mean age was 42 ± 15 years, 40 (56%) were male, 20 (28%) had loss of consciousness, and mean initial carboxyhemoglobin was 22 ± 9%. The rate of six-week neuropsychological sequelae was 50% in the one-HBO2 session group and 55% in the three-HBO2 sessions group (p = 0.80), and at six months was 42% versus 46%, respectively (p = 0.76). Conclusions: There was no difference in the rate of neuropsychological sequelae in those who received three HBO2 sessions and those who received one HBO2 sessions and two sham sessions. The higher rate of neuropsychological sequelae compared to an earlier study may be due to neuropsychological test-retest effects or previously identified risk factors for cognitive sequelae (age, duration of poisoning, cerebellar dysfunction). This study's rates of cognitive difficulties, affective complaints, and other symptoms suggest brain injury after CO poisoning is common.

A composite outcome for mild traumatic brain injury in trials of hyperbaric oxygen.

INTRODUCTION: Global outcomes can strengthen inferences from clinical trials. We evaluate global outcomes for persistent post-concussive symptoms (PCS) after mild traumatic brain injury (mTBI) in two clinical trials of hyperbaric oxygen (HBO2) in United States service members. METHODS: During study design, outcomes of symptom, cognitive, and functional impairments planned for a trial of HBO2 for PCS (HOPPS) were weighted and grouped into different domains to formulate the composite outcome total score. The composite outcome was compared between the intervention groups in HOPPS and those in a subsequent HBO2 trial (BIMA) for validation. Additionally, two post hoc global outcome measures were explored, including one composed of components that demonstrated favorable characteristics in both studies and another via components used in another TBI randomized trial (COBRIT). RESULTS: In total, 143 active-duty or veteran military personnel were randomized across the two studies. Composite total scores improved from baseline for HBO2 (mean ± SD -2.9±9.0) and sham (-2.9±6.6) groups in HOPPS but did not differ significantly between groups (p=0.33). In BIMA, 13-week changes from baseline favored the HBO2 group (-3.6±6.4) versus sham (-0.3±5.2; p=0.02). No between-group differences were found when COBRIT composite scoring was applied to BIMA. Overall, HBO2 effects were maximized when the post hoc global measure derived from both studies was applied to the data. CONCLUSIONS: Composite total scores in HOPPS and BIMA were consistent with primary study results. The global measures considered may offer utility as endpoints to achieve maximal HBO2 effect in future trials of the mTBI population. IDS: clinicaltrials.gov Identifiers NCT01611194 (BIMA) and NCT01306968 (HOPPS).

Adverse events and blinding in two randomized trials of hyperbaric oxygen for persistent post-concussive symptoms.

Safety monitoring and successful blinding are important features of randomized, blinded clinical trials. We report chamber- and protocol-related adverse events (AEs) for participants enrolled in two randomized, double-blind clinical trials of hyperbaric oxygen (HBO2) for persistent post-concussive symptoms clinicaltrials.gov identifiers NCT01306968, HOPPS, and NCT01611194, BIMA), as well as the success of maintaining the blind with a low-pressure sham control arm. In both studies, participants were randomized to receive HBO2 (1.5 atmospheres absolute, >99% oxygen) or sham chamber sessions (1.2 atmospheres absolute, room air). In 143 participants undergoing 4,245 chamber sessions, chamber-related adverse events were rare (1.1% in the HOPPS study, 2.2% in the BIMA study). Minor, non-limiting barotrauma was the most frequently reported. Rarely, some participants experienced headache with chamber sessions. No serious adverse events were associated with chamber sessions. An allocation questionnaire completed after intervention revealed that the sham control arm adequately protected the blind in both trials. Participants based allocation assumptions on symptom improvement or lack of symptom improvement and could not discern intervention arm by pressure, smell, taste, or gas flow.

Extended follow-up in a randomized trial of hyperbaric oxygen for persistent post-concussive symptoms.

To date, several Department of Defense (DoD) and civilian studies have evaluated hyperbaric oxygen for mild forms of traumatic brain injury. Prior to the DoD-sponsored "Brain Injury and Mechanisms of Action of Hyperbaric Oxygen for Persistent Post-Concussive Symptoms after Mild Traumatic Brain Injury (mTBI) (BIMA)" trial, none included post-intervention follow-up beyond three to six months. Post-hoc attempts at long-term follow-up were complicated by low participation and potential self-selection bias. BIMA planned for follow-up through 12 months but was amended to add post-concussive and post-traumatic stress disorder, quality of life, pain, depression, anxiety, and alcohol use assessments at 24 and 36 months. A total of 42 of 71 BIMA participants consented to extendedfollow-up, and 40 and 14 completed a 24- or 36-month visit, respectively, representing an overall response rate of 59% and 20%. Participants who completed extended follow-up were similar to the study group that did not in terms of demographics, perceived intervention allocation, and initial response to intervention. There were no significant differences at 24 or 36 months between intervention groups, and group mean scores were near pre-intervention values. This return to baseline could be due to waning treatment effect, selection bias, or participant or perception effects. Though BIMA implemented several participant retention strategies, more frequent participant contact and increased compensation might improve long-term retention in future studies. clinicaltrials.gov Identifier NCT01611194.

Self-affirmation improves self-control over snacking among participants low in eating self-efficacy.

OBJECTIVE: Individuals low in eating self-efficacy are at particular risk of engaging in unhealthy eating behaviours, including the consumption of high calorie snacks. The elevated levels of snacking displayed by these individuals can largely be attributed to their experiencing low self-control over the avoidance of such foods (Hankonen, Kinnunen, Absetz, & Jallinoja, 2014). Interventions are thus required to boost self-control over snacking among those low in eating self-efficacy. Self-affirmation has been shown to boost self-control among individuals with depleted resources in other domains (Schmeichel & Vohs, 2009). The purpose of the current study was to test the hypothesis that a self-affirmation manipulation would similarly increase self-control over snacking for individuals low in eating self-efficacy. METHODS: At baseline, participants (N = 70) completed measures of dietary restraint and eating self-efficacy. In the main study, participants completed either a self-affirmation or a control task immediately before undertaking a joystick category judgment task that assessed self-control over snacking. RESULTS: Hierarchical multiple regression analysis revealed the predicted significant interaction between eating self-efficacy and self-affirmation, demonstrating that self-affirmation moderated the association between eating self-efficacy and self-control over snacking. Johnson-Neyman regions of significance confirmed that for participants low in eating self-efficacy the self-affirmation manipulation resulted in higher levels of self-control. Unexpectedly, however, for participants high in eating self-efficacy the self-affirmation manipulation was found to be associated with lower levels of self-control. CONCLUSIONS: Findings supported the hypothesis that a self-affirmation manipulation would boost self-control over snacking among individuals low in eating self-efficacy. Self-affirmation may thus provide a useful technique for strengthening self-control in relation to the avoidance of unhealthy foods among individuals who find it difficult to manage challenging dietary situations.

Hyperbaric oxygen for post-concussive symptoms in United States military service members: a randomized clinical trial.

BACKGROUND: In prior military randomized trials, participants with persistent symptoms after mild traumatic brain injury (TBI) reported improvement regardless of receiving hyperbaric oxygen (HBO2) or sham intervention. This study's objectives were to identify outcomes for future efficacy trials and describe changes by intervention. METHODS: This Phase II, randomized, double-blind, sham-controlled trial enrolled military personnel with mild TBI and persistent post-concussive symptoms. Participants were randomized to receive 40 HBO2 (1.5 atmospheres absolute (ATA), ⟩99% oxygen, 60 minutes) or sham chamber sessions (1.2 ATA, room air, 60 minutes) over 12 weeks. Participants and evaluators were blinded to allocation. Outcomes assessed at baseline, 13 weeks and six months included symptoms, quality of life, neuropsychological, neurological, electroencephalography, sleep, auditory, vestibular, autonomic, visual, neuroimaging, and laboratory testing. Participants completed 12-month questionnaires. Intention-to-treat results are reported. RESULTS: From 9/11/2012 to 5/19/2014, 71 randomized participants received HBO2 (n=36) or sham (n=35). At baseline, 35 participants (49%) met post-traumatic stress disorder (PTSD) criteria. By the Neurobehavioral Symptom Inventory, the HBO2 group had improved 13-week scores (mean change -3.6 points, P=0.03) compared to sham (+3.9 points). In participants with PTSD, change with HBO2 was more pronounced (-8.6 vs. +4.8 points with sham, P=0.02). PTSD symptoms also improved in the HBO2 group, and more so in the subgroup with PTSD. Improvements regressed at six and 12 months. Hyperbaric oxygen improved some cognitive processing speed and sleep measures. Participants with PTSD receiving HBO2 had improved functional balance and reduced vestibular complaints at 13 weeks. CONCLUSIONS: By 13 weeks, HBO2 improved post-concussive and PTSD symptoms, cognitive processing speed, sleep quality, and balance function, most dramatically in those with PTSD. Changes did not persist beyond six months. Several outcomes appeared sensitive to change; additional studies are warranted.

Persuading People to Drink Less Alcohol: The Role of Message Framing, Temporal Focus and Autonomy.

AIMS: Health information can be used to try to persuade people to follow safe drinking recommendations. However, both the framing of information and the dispositional characteristics of message recipients need to be considered. An online study was conducted to examine how level of autonomy moderated the effect on drinking behaviour of gain- and loss-framed messages about the short- vs. long-term consequences of alcohol use. METHODS: At Time 1, participants (N = 335) provided demographic information and completed a measure of autonomy. At Time 2, participants reported baseline alcohol use and read a gain-framed or loss-framed health message that highlighted either short- or long-term outcomes of alcohol consumption. Alcohol consumption was reported 7 days later. RESULTS: The results showed a significant three-way interaction between message framing (loss vs. gain), temporal focus (short-term vs. long-term) and autonomy. For low-autonomy (but not high-autonomy) individuals, the loss-framed health message was associated with lower levels of alcohol consumption than was the gain-framed message but only if the short-term outcomes were conveyed. CONCLUSION: This research provides evidence that the interaction between message framing and temporal focus may depend on a person's level of autonomy, which has implications for health promotion and the construction of effective health communication messages. SHORT SUMMARY: We examined how autonomy moderated the effect on drinking behaviour of gain- and loss-framed messages about the short- vs. long-term consequences of alcohol use. For low-autonomy individuals, the loss-framed health message was associated with lower alcohol consumption than was the gain-framed message but only if the short-term outcomes were conveyed.

Hyperbaric oxygen for mild traumatic brain injury: Design and baseline summary.

The Brain Injury and Mechanisms of Action of Hyperbaric Oxygen for Persistent Post-Concussive Symptoms after Mild Traumatic Brain Injury (mTBI) (BIMA) study, sponsored by the Department of Defense, is a randomized double-blind, sham-controlled clinical trial that has a longer duration of follow-up and more comprehensive assessment battery compared to recent HBO2 studies. BIMA randomized 71 participants from September 2012 to May 2014. Primary results are expected in 2017. Randomized military personnel received hyperbaric oxygen (HBO2) at 1.5 atmospheres absolute (ATA) or sham chamber sessions at 1.2 ATA, air, for 60 minutes daily for 40 sessions. Outcomes include neuropsychological, neuroimaging, neurological, vestibular, autonomic function, electroencephalography, and visual systems evaluated at baseline, immediately following intervention at 13 weeks and six months with self-report symptom and quality of life questionnaires at 12 months, 24 months and 36 months. Characteristics include: median age 33 years (range 21-53); 99% male; 82% Caucasian; 49% diagnosed post-traumatic stress disorder; 28% with most recent injury three months to one year prior to enrollment; 32% blast injuries; and 73% multiple injuries. This manuscript describes the study design, outcome assessment battery, and baseline characteristics. Independent of a therapeutic role of HBO2, results of BIMA will aid understanding of mTBI. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01611194; https://clinicaltrials.gov/show/NCT01611194.

Carbon monoxide poisoning in Utah: 1996-2013.

INTRODUCTION: The true incidence of carbon monoxide (CO) poisoning is not clearly known, but a description of possible trends could aid in prevention. METHODS: Investigators searched Utah state databases for emergency department (ED) visits and admissions for CO poisoning and medical examiner records for CO-related fatalities. RESULTS: From 1996-2013, 7,590 individuals were diagnosed with CO poisoning: 6,469 were treated/ released from EDs; 596 were admitted; 525 died. Of 7,065 non-fatal poisonings, 5,950 (84%) were accidental and 498 (7%) were suicide attempts. Few patients (9.7%) were treated with hyperbaric oxygen. For accidental poisonings, internal combustion engines accounted for 43%, smoke inhalation, 34%, and heating sources, 22%. Internal combustion engines were implicated in 97% of suicide attempts. Non-fatal poisonings declined following a 2008 legislative change requiring CO alarms in residences, but we do not know if legislation caused the decline. One hundred forty-one (27%) fatal poisonings were accidental, 361 (70%) suicides and two (0.4%) homicides. Victims with cardiovascular autopsy findings/past cardiovascular history had lower carboxyhemoglobin levels (mean 51.2%, n=53) compared to those without (70.8%, n=472). Mean postmortem carboxyhemoglobin was highest in ages 20-29 years (72.5%). CONCLUSIONS: The incidence of CO poisoning in Utah is declining, but CO poisoning is still common. Alarm legislation may aid prevention efforts. An educational campaign addressing the many causes and circumstances of CO poisoning is required for prevention.

Rates of visual acuity change in patients receiving hyperbaric oxygen in monoplace and multiplace chambers.

INTRODUCTION: Changes in visual acuity are a known side effect of hyperbaric oxygen (HBO2). We conducted a quality improvement initiative to better quantify visual change risk and to identify possible risk factors. METHODS: Vision was checked weekly in a clinical HBO2 population by Snellen eye chart. Visual acuity change was defined as Snellen test worsened to 20/40 or greater or by loss of 2 lines. RESULTS: Of 85 patients treated from January 2013 to February 2015 with 10 HBO2 sessions and ≥ 2 weeks of visual acuity testing, 53 (62%) were male. All were treated for UHMS-approved indications. A total of 34 patients (40%) had no change in visual acuity, 27 (32%) had a 1-line change, and 24 (28%) had at least a 2-line worsening in visual acuity. The number of sessions for those with at least a 2-line change was 36 ± 15 (15-60). A 2-line change occurred at similar rates for monoplace and multiplace patients (29% and 32%, respectively), but monoplace patients more frequently reached 20/40 or worse (32% vs. 18%). Seven of 11 patients with existing cataracts had ≥ 2 line change, as did six of 14 patients (43%) with a history of head/neck radiation. CONCLUSIONS: In this retrospective review of quality improvement data, 28% of patients had a 2-line change in visual acuity by Snellen exam after treat-ment with HBO2. Further study of possible risk factors, including chamber type, is warranted.

Executive summary: The Brain Injury and Mechanism of Action of Hyperbaric Oxygen for Persistent Post-Concussive Symptoms after Mild Traumatic Brain Injury (mTBI) (BIMA) Study.

The Brain Injury and Mechanism of Action of Hyperbaric Oxygen for Persistent Post-Concussive Symptoms after Mild Traumatic Brain Injury (mTBI) (BIMA) study, sponsored by the Department of Defense and held under an investigational new drug application by the Office of the Army Surgeon General, is one of the largest and most complex clinical trials of hyperbaric oxygen (HBO2) for post-concussive symptoms (PCS) in U.S. military service members.

Linear analysis of heart rate variability in post-concussive syndrome.

Heart rate variability (HRV) represents measurable output of coordinated structural and functional systems within the body and brain. Both mild traumatic brain injury (mTBI) and HRV are modulated by changes in autonomic nervous system function. We present baseline HRV results from an ongoing mTBI clinical trial. HRV was assessed via 24-hour ambulatory electrocardiography; recordings were segmented by physiological state (sleep, wakefulness, exercise, standing still). Time, frequency, and spatial domain measures were summarized and compared with symptoms, sleep quality, and neurological examination. Median low frequency/high frequency (LF/HF) ratio exceeded 1.0 across segments, indicating prevalence of sympathetic modulation. Abnormal Sharpened Romberg Test was associated with 29% LF/HF decrease (95% CI [2.1, 47.7], p=0.04); pathological nystagmus associated with decreased standard deviation of electrocardiogram R-R interval (SDNN) index (25% decrease, 95% CI [0.8, 43.4], p=0.04). Increased sympathetic modulation was associated with increased anger scores (19% LF/HF increase with 5-point State Trait Anger Expression Inventory-2 trait anger increase (95% CI [1.2, 39.1], p=0.04)). A 13% HF increase (95% CI [2.1, 25.7], p=0.02) was observed with increased Pittsburgh Sleep Quality Index scores. These results support autonomic nervous system dysfunction in service members after mTBI. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01611194; https://clinicaltrials.gov/show/NCT01611194.

Sleep assessments for a mild traumatic brain injury trial in a military population.

Baseline sleep characteristics were explored for 71 U.S. military service members with mild traumatic brain injury (mTBI) enrolled in a post-concussive syndrome clinical trial. The Pittsburgh Sleep Quality Index (PSQI), sleep diary, several disorder-specific questionnaires, actigraphy and polysomnographic nap were collected. Almost all (97%) reported ongoing sleep problems. The mean global PSQI score was 13.5 (SD=3.8) and 87% met insomnia criteria. Sleep maintenance efficiency was 79.1% for PSQI, 82.7% for sleep diary and 90.5% for actigraphy; total sleep time was 288, 302 and 400 minutes, respectively. There was no correlation between actigraphy and subjective questionnaires. Overall, 70% met hypersomnia conditions, 70% were at high risk for obstructive sleep apnea (OSA), 32% were symptomatic for restless legs syndrome, and 6% reported cataplexy. Nearly half (44%) reported coexisting insomnia, hypersomnia and high OSA risk. Participants with post-traumatic stress disorder (PTSD) had higher PSQI scores and increased OSA risk. Older participants and those with higher aggression, anxiety or depression also had increased OSA risk. The results confirm poor sleep quality in mTBI with insomnia, hypersomnia, and OSA risk higher than previously reported, and imply sleep disorders in mTBI may be underdiagnosed or exacerbated by comorbid PTSD.

Hyperbaric oxygen for persistent post-concussive symptoms: long-term follow-up.

We report results of an observational cohort study investigating long-term follow-up in participants from two completed United States military trials of hyperbaric oxygen (HBO2) for persistent post-concussive symptoms (PCS), as well as challenges in recruitment and retention in active-duty military personnel. After informed consent, participants completed an electronic survey assessing PCS, post-traumatic stress disorder (PTSD), anxiety, depression and quality of life. Of 132 HBO2 study participants, 40 (30%) completed the survey (42 could not be contacted; 50 were lost to follow-up or declined). All were male, age 28.1 ±6.6 years (mean ±1SD). Time to follow-up was 39.2 ±6.1 months. At follow-up, participants reported continued symptoms of PTSD, depression, anxiety and reduced quality of life. Among DARPA/VCU study participants, total PCS scores worsened in the 1.5 atmospheres absolute (ATA) equivalent HBO2 group (mean change 7.4 ±15.8) and improved in the sham (-8.0 ±7.7) and 2.0 atmospheres absolute equivalent HBO2 groups (-3.3 ±7.4). Individual changes varied widely, range -23 to +28 points. In participants from the HOPPS study, total PCS scores worsened in all groups: local care (10.5 ±8.7), sham (7.9 ±11.9) and 1.5 ATA HBO2 (1.0 ±19.4). In this limited, cross-sectional sample, PCS and PTSD symptoms did not appear to improve over time by descriptive analyses. Low participation rates and potential response bias limit our ability to perform statistical hypothesis testing and to draw conclusions from these data. Future studies should prospectively plan longitudinal follow-up and regular engagement with participants to minimize attrition.

Spontaneous cerebral gas embolism and pulmonary arteriovenous malformation: a case report.

Pulmonary barotrauma can cause cerebral arterial gas embolism (CAGE) from pulmonary overdistension of alveoli forcing gas into the pulmonary vasculature. We report a case of CAGE in a man found to have occult pulmonary arteriovenous malformation (PAVM) and undiagnosed obstructive sleep apnea (OSA). A 46-year-old man was admitted to the hospital for an acute seizure and left-sided weakness, with telangiectasias on his lower lip and tongue. Brain-computed tomography (CT) showed gas emboli in the right hemisphere. Chest CT revealed a 1.8-cm PAVM in the posterior right costophrenic sulcus. A transthoracic echocardiogram showed no intracardiac shunt or patent foramen ovale. He was treated with phenytoin, lidocaine and hyperbaric oxygen. The PAVM was occluded with a detachable balloon followed by coil embolization. Polysomnography revealed severe obstructive sleep apnea, which was treated with CPAP. Seven years later, the patient was functioning at his pre-event baseline. We propose the CAGE was caused by high negative intrathoracic pressures while breathing against an obstructed upper airway, with air entrainment into the PAVM and subsequent arterialization.

Promoting the avoidance of high-calorie snacks. The role of temporal message framing and eating self-efficacy.

BACKGROUND: Message framing outcomes of healthy behaviours as occurring 'every day' vs. 'every year' can influence the temporal proximity and perceived likelihood of these outcomes. However, it is not known how pre-existing beliefs such as confidence in one's ability to perform health-related behaviour interact with such messages. OBJECTIVE: The purpose of this research was to investigate whether eating self-efficacy moderates the effect of temporal framing (day-frame vs. year-frame) on snacking behaviour. METHODS: Participants (N = 95) completed the short form of the Weight Efficacy Lifestyle Questionnaire (WEL-SF) and read either a day-framed or year-framed message about the health benefits associated with avoiding snacking. Consumption of snacks was reported 7 days later. FINDINGS: For those with low levels of eating self-efficacy (WEL-SF score < 4.3 on a 7-point response scale), the year-framed message was associated with lower levels of snacking than the day-framed message. DISCUSSION: The current research identifies a key role for eating self-efficacy in shaping recipients' responses to temporally framed messages about the health benefits associated with the avoidance of snacking.

A prospective trial of hyperbaric oxygen for chronic sequelae after brain injury (HYBOBI).

OBJECTIVE: Some practitioners advocate hyperbaric oxygen (HBO2) for sequelae following brain injury. This study assessed recruitment, tolerance and safety in preparation for a randomized clinical trial. DESIGN: Prospective, open-label feasibility study. SETTING: Hyperbaric medicine department of a tertiary academic hospital. PARTICIPANTS: Participatory adult outpatients with problems from stroke (n=22), anoxia (13) or trauma (28) that occurred at least 12 months before enrollment, without contraindications to HBO2. Sixty-three participants enrolled in the study (21 females,42 males). Age was 45 +/- 16 years (18-76) and time from injury was 6.9 +/- 7.1 years (1.0-29.3). Fifty-three completed the study intervention, and 55 completed the assessment battery. METHODS: PARTICIPANTS underwent 60 daily HBO2 sessions (1.5 atm abs, 100% oxygen, 60 minutes). Assessments were conducted at baseline, after the HBO2 course, and six months later. MAIN OUTCOME MEASUREMENTS: The prime outcome was feasibility. To estimate the immediate and long-term effects of HBO2, we assessed neuropsychological measures, questionnaires, neurologic exam and physical functioning measures. Some participants also had pre- and post-HBO2 speech evaluation (n=27) and neuroimaging (n=17). RESULTS: The study met our a priori definition for feasibility for recruitment, but 44% required additional time to complete the 60 sessions (up to 105 days). HBO2-related adverse events were rare and not serious. Although many participants reported improvement in symptoms (51% memory, 51% attention/concentration, 48% balance/coordination, 45% endurance, 20% sleep) post-HBO2, and 93% reported that they would participate in the study again, no standardized testing showed clinically important improvement. In the small subset of those undergoing neuroimaging, apparent improvement was observed in auditory functional MRI (8/13), MR spectroscopy (9/17) and brain perfusionby CT angiography (5/9). CONCLUSIONS: Conducting an HBO2 clinical trial in this population was feasible. Although many participants reported improvement, the lack of concurrent controls limits the strength of inferences from this trial, especially considering lack of change in standardized testing. The clinical relevance of neuroimaging changes is unknown. The findings of this study may indicate a need for caution when considering the broad application of HBO2 more than one year after brain injury due to stroke, severe TBI and anoxia, until there is more compelling evidence from carefully designed sham-controlled, blinded clinical trials.