Thalamocortical connectivity and its relationship with symptoms and cognition across the psychosis continuum

BACKGROUND

Coordination between the thalamus and cortex is necessary for efficient processing of sensory information and appears disrupted in schizophrenia. The significance of this disrupted coordination (i.e. thalamocortical dysconnectivity) to the symptoms and cognitive deficits of schizophrenia is unclear. It is also unknown whether similar dysconnectivity is observed in other forms of psychotic psychopathology and associated with familial risk for psychosis. Here we examine the relevance of thalamocortical connectivity to the clinical symptoms and cognition of patients with psychotic psychopathology, their first-degree biological relatives, and a group of healthy controls.

METHOD

Patients with a schizophrenia-spectrum diagnosis (N = 100) or bipolar disorder with a history of psychosis (N = 33), their first-degree relatives (N = 73), and a group of healthy controls (N = 43) underwent resting functional MRI in addition to clinical and cognitive assessments as part of the Psychosis Human Connectome Project. A bilateral mediodorsal thalamus seed-based analysis was used to measure thalamocortical connectivity and test for group differences, as well as associations with symptomatology and cognition.

RESULTS

Reduced connectivity from mediodorsal thalamus to insular, orbitofrontal, and cerebellar regions was seen in schizophrenia. Across groups, greater symptomatology was related to less thalamocortical connectivity to the left middle frontal gyrus, anterior cingulate, right insula, and cerebellum. Poorer cognition was related to less thalamocortical connectivity to bilateral insula. Analyses revealed similar patterns of dysconnectivity across patient groups and their relatives.

CONCLUSIONS

Reduced thalamo-prefrontal-cerebellar and thalamo-insular connectivity may contribute to clinical symptomatology and cognitive deficits in patients with psychosis as well as individuals with familial risk for psychotic psychopathology.

The CBIT + TMS trial: study protocol for a two-phase randomized controlled trial testing neuromodulation to augment behavior therapy for youth with chronic tics

BACKGROUND

Comprehensive Behavioral Intervention for Tics (CBIT) is a first-line treatment for tic disorders that aims to improve controllability over tics that an individual finds distressing or impairing. However, it is only effective for approximately half of patients. Supplementary motor area (SMA)-directed neurocircuitry plays a strong role in motor inhibition, and activity in this region is thought to contribute to tic expression. Targeted modulation of SMA using transcranial magnetic stimulation (TMS) may increase CBIT efficacy by improving patients' ability to implement tic controllability behaviors.

METHODS

The CBIT + TMS trial is a two-phase, milestone-driven early-stage randomized controlled trial. The trial will test whether augmenting CBIT with inhibitory, non-invasive stimulation of SMA with TMS modifies activity in SMA-mediated circuits and enhances tic controllability in youth ages 12-21 years with chronic tics. Phase 1 will directly compare two rTMS augmentation strategies (1 Hz rTMS vs. cTBS) vs. sham in N = 60 participants. Quantifiable, a priori "Go/No Go Criteria" guide the decision to proceed to phase 2 and the selection of the optimal TMS regimen. Phase 2 will compare the optimal regimen vs. sham and test the link between neural target engagement and clinical outcomes in a new sample of N = 60 participants.

DISCUSSION

This clinical trial is one of few to date testing TMS augmentation of therapy in a pediatric sample. The results will provide insight into whether TMS is a potentially viable strategy for enhancing CBIT efficacy and reveal potential neural and behavioral mechanisms of change.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04578912 . Registered on October 8, 2020.

The CBIT+TMS Trial: study protocol for a two-phase randomized controlled trial testing neuromodulation to augment behavior therapy for youth with chronic tics

Background

Comprehensive Behavioral Intervention for Tics (CBIT) is a first-line treatment for tic disorders that aims to improve controllability over tics that an individual finds distressing or impairing. However, it is only effective for approximately half of patients. Supplementary motor area (SMA)-directed neurocircuitry plays a strong role in motor inhibition, and activity in this region is thought to contribute to tic expression. Targeted modulation of SMA using transcranial magnetic stimulation (TMS) may increase CBIT efficacy by improving patient ability to implement tic controllability behaviors.

Methods

The CBIT+TMS trial is a two-phase, milestone driven early-stage randomized controlled trial. The trial will test whether augmenting CBIT with inhibitory, noninvasive stimulation of SMA with TMS modifies activity in SMA-mediated circuits and enhances tic controllability in youth ages 12-21 years with chronic tics. Phase 1 will directly compare two rTMS augmentation strategies (1Hz rTMS vs. cTBS) vs. sham in N = 60 participants. Quantifiable, a priori "Go/No Go Criteria" guide the decision to proceed to Phase 2 and selection of the optimal TMS regimen. Phase 2 will compare the optimal regimen vs. sham and test the link between neural target engagement and clinical outcomes in a new sample of N = 60 participants.

Discussion

This clinical trial is one of few to date testing TMS augmentation of therapy in a pediatric sample. Results will provide insight into whether TMS is a potentially viable strategy for enhancing CBIT efficacy and reveal potential neural and behavioral mechanisms of change.

Trial registration

ClinicalTrials.gov Identifier: NCT04578912.

Gingival Conditioning with Provisional Composite Veneer Prior to Final Dental Restoration: Three-year Follow-up

This manuscript reports a three-year follow-up of a case of gingival conditioning with a provisional composite veneer prior to diastema closure and tooth recontouring with direct composites. This conservative treatment resulted in a natural and harmonious smile.

Structural and Functional Neural Correlates of Treatment Response for Interpersonal Psychotherapy for Depressed Adolescents

Precision medicine approaches hold tremendous promise to advance current clinical practice by providing information about which individuals will benefit from which treatments. This pilot study evaluated if baseline structure and function of the salience and emotion brain regions implicated in adolescent depression, specifically the amygdala and anterior cingulate cortex (ACC), predict response to Interpersonal Psychotherapy for Depressed Adolescents (IPT-A). Adolescents (n = 15; mean age = 14.5 (1.6); 80.0% female) diagnosed with a depressive disorder completed brain scans before the start of a 16 week trial of IPT-A. Clinical measures assessing depressive symptoms were completed before, during, and after a trial of therapy. Results show that at baseline, greater ACC activation in the context of an emotion-matching task and greater amygdala-ACC resting-state functional connectivity was related to greater improvement in depression symptoms. There was minimal evidence that brain structure predicted changes in depressive symptoms. The present study is the first to evaluate neural predictors of IPT-A response. While the results are preliminary, these findings suggest some avenues for future research to pursue in the hopes that more will benefit from treatment.

Cortical thickness and resting-state cardiac function across the lifespan: A cross-sectional pooled mega-analysis

Understanding the association between autonomic nervous system [ANS] function and brain morphology across the lifespan provides important insights into neurovisceral mechanisms underlying health and disease. Resting-state ANS activity, indexed by measures of heart rate [HR] and its variability [HRV] has been associated with brain morphology, particularly cortical thickness [CT]. While findings have been mixed regarding the anatomical distribution and direction of the associations, these inconsistencies may be due to sex and age differences in HR/HRV and CT. Previous studies have been limited by small sample sizes, which impede the assessment of sex differences and aging effects on the association between ANS function and CT. To overcome these limitations, 20 groups worldwide contributed data collected under similar protocols of CT assessment and HR/HRV recording to be pooled in a mega-analysis (N = 1,218 (50.5% female), mean age 36.7 years (range: 12-87)). Findings suggest a decline in HRV as well as CT with increasing age. CT, particularly in the orbitofrontal cortex, explained additional variance in HRV, beyond the effects of aging. This pattern of results may suggest that the decline in HRV with increasing age is related to a decline in orbitofrontal CT. These effects were independent of sex and specific to HRV; with no significant association between CT and HR. Greater CT across the adult lifespan may be vital for the maintenance of healthy cardiac regulation via the ANS-or greater cardiac vagal activity as indirectly reflected in HRV may slow brain atrophy. Findings reveal an important association between CT and cardiac parasympathetic activity with implications for healthy aging and longevity that should be studied further in longitudinal research.

Nutritional support during the hospital stay reduces mortality in patients with different types of cancers: secondary analysis of a prospective randomized trial

BACKGROUND

Nutritional support in patients with cancer aims at improving quality of life. Whether use of nutritional support is also effective in improving clinical outcomes requires further study.

PATIENTS AND METHODS

In this preplanned secondary analysis of patients with cancer included in a prospective, randomized-controlled, Swiss, multicenter trial (EFFORT), we compared protocol-guided individualized nutritional support (intervention group) to standard hospital food (control group) regarding mortality at 30-day (primary endpoint) and other clinical outcomes.

RESULTS

We analyzed 506 patients with a main admission diagnosis of cancer, including lung cancer (n = 113), gastrointestinal tumors (n = 84), hematological malignancies (n = 108) and other types of cancer (n = 201). Nutritional risk based on Nutritional Risk Screening (NRS 2002) was an independent predictor for mortality over 180 days with an (age-, sex-, center-, type of cancer-, tumor activity- and treatment-) adjusted hazard ratio of 1.29 (95% CI 1.09-1.54; P = 0.004) per point increase in NRS. In the 30-day follow-up period, 50 patients (19.9%) died in the control group compared to 36 (14.1%) in the intervention group resulting in an adjusted odds ratio of 0.57 (95% CI 0.35-0.94; P = 0.027). Interaction tests did not show significant differences in mortality across the cancer type subgroups. Nutritional support also significantly improved functional outcomes and quality of life measures.

CONCLUSIONS

Compared to usual hospital nutrition without nutrition support, individualized nutritional support reduced the risk of mortality and improved functional and quality of life outcomes in cancer patients with increased nutritional risk. These data further support the inclusion of nutritional care in cancer management guidelines.

Network topology changes in chronic mild traumatic brain injury (mTBI)

BACKGROUND

In mild traumatic brain injury (mTBI), diffuse axonal injury results in disruption of functional networks in the brain and is thought to be a major contributor to cognitive dysfunction even years after trauma.

OBJECTIVE

Few studies have assessed longitudinal changes in network topology in chronic mTBI. We utilized a graph theoretical approach to investigate alterations in global network topology based on resting-state functional connectivity in veterans with chronic mTBI.

METHODS

50 veterans with chronic mTBI (mean of 20.7 yrs. from trauma) and 40 age-matched controls underwent two functional magnetic resonance imaging scans 18 months apart. Graph theory analysis was used to quantify network topology measures (density, clustering coefficient, global efficiency, and modularity). Hierarchical linear mixed models were used to examine longitudinal change in network topology.

RESULTS

With all network measures, we found a significant group × time interaction. At baseline, brain networks of individuals with mTBI were less clustered (p = 0.03) and more modular (p = 0.02) than those of HC. Over time, the mTBI networks became more densely connected (p = 0.002), with increased clustering (p = 0.001) and reduced modularity (p < 0.001). Network topology did not change across time in HC.

CONCLUSION

These findings demonstrate that brain networks of individuals with mTBI remain plastic decades after injury and undergo significant changes in network topology even at the later phase of the disease.

Brain Density Clustering Analysis: A New Approach to Brain Functional Dynamics

BACKGROUND

A number of studies in recent years have explored whole-brain dynamic connectivity using pairwise approaches. There has been less focus on trying to analyze brain dynamics in higher dimensions over time.

METHODS

We introduce a new approach that analyzes time series trajectories to identify high traffic nodes in a high dimensional space. First, functional magnetic resonance imaging (fMRI) data are decomposed using spatial ICA to a set of maps and their associated time series. Next, density is calculated for each time point and high-density points are clustered to identify a small set of high traffic nodes. We validated our method using simulations and then implemented it on a real data set.

RESULTS

We present a novel approach that captures dynamics within a high dimensional space and also does not use any windowing in contrast to many existing approaches. The approach enables one to characterize and study the time series in a potentially high dimensional space, rather than looking at each component pair separately. Our results show that schizophrenia patients have a lower dynamism compared to healthy controls. In addition, we find patients spend more time in nodes associated with the default mode network and less time in components strongly correlated with auditory and sensorimotor regions. Interestingly, we also found that subjects oscillate between state pairs that show opposite spatial maps, suggesting an oscillatory pattern.

CONCLUSION

Our proposed method provides a novel approach to analyze the data in its native high dimensional space and can possibly provide new information that is undetectable using other methods.

Dentate gyrus volume deficit in schizophrenia

BACKGROUND

Schizophrenia is associated with robust hippocampal volume deficits but subregion volume deficits, their associations with cognition, and contributing genes remain to be determined.

METHODS

Hippocampal formation (HF) subregion volumes were obtained using FreeSurfer 6.0 from individuals with schizophrenia (n = 176, mean age ± s.d. = 39.0 ± 11.5, 132 males) and healthy volunteers (n = 173, mean age ± s.d. = 37.6 ± 11.3, 123 males) with similar mean age, gender, handedness, and race distributions. Relationships between the HF subregion volume with the largest between group difference, neuropsychological performance, and single-nucleotide polymorphisms were assessed.

RESULTS

This study found a significant group by region interaction on hippocampal subregion volumes. Compared to healthy volunteers, individuals with schizophrenia had significantly smaller dentate gyrus (DG) (Cohen's d = -0.57), Cornu Ammonis (CA) 4, molecular layer of the hippocampus, hippocampal tail, and CA 1 volumes, when statistically controlling for intracranial volume; DG (d = -0.43) and CA 4 volumes remained significantly smaller when statistically controlling for mean hippocampal volume. DG volume showed the largest between group difference and significant positive associations with visual memory and speed of processing in the overall sample. Genome-wide association analysis with DG volume as the quantitative phenotype identified rs56055643 (β = 10.8, p < 5 × 10-8, 95% CI 7.0-14.5) on chromosome 3 in high linkage disequilibrium with MOBP. Gene-based analyses identified associations between SLC25A38 and RPSA and DG volume.

CONCLUSIONS

This study suggests that DG dysfunction is fundamentally involved in schizophrenia pathophysiology, that it may contribute to cognitive abnormalities in schizophrenia, and that underlying biological mechanisms may involve contributions from MOBP, SLC25A38, and RPSA.

In-vivo cortical thickness estimation from high-resolution T1w MRI scans in healthy and mucopolysaccharidosis affected dogs

Cortical thickness measurement estimated from high-resolution anatomical MRI scans may serve as a marker of cortical atrophy in clinical research applications. Most of the working algorithms and pipelines are optimized for human in-vivo data analyses that offer robust and reproducible measures. As animal-models are widely utilized in many preclinical phases of clinical trials the need for an optimized automated MRI data analysis to yield reliable data is warranted. We present a processing pipeline optimized for cortical thickness estimation of canine brains in native and template spaces. Preliminary results of 5 healthy and 5 mucopolysaccharidosis (MPS) dogs demonstrate single-canine mean/median cortical thickness in range of 2.69-3.58mm in native space and 3.26-4.15mm in template space. Our MRI generated values exceed previous histological measurements (observed mean about 2mm) in limited literature reports. Randomly selected manual measures corroborated the ranges defined by estimated cortical thickness probability density functions. Geometric transformations between native and template spaces change absolute mean/median cortical thickness values, but do not change the data nature and properties since the Pearson correlation coefficients between different space estimates were 0.84 for mean values and 0.89 for median values. No significant difference in total cortical thickness between MPS and age-and gender-matched dogs was observed.

Weighted average of shared trajectory: A new estimator for dynamic functional connectivity efficiently estimates both rapid and slow changes over time

BACKGROUND

Dynamic functional network connectivity (dFNC) of the brain has attracted considerable attention recently. Many approaches have been suggested to study dFNC with sliding window Pearson correlation (SWPC) being the most well-known. SWPC needs a relatively large sample size to reach a robust estimation but using large window sizes prevents us to detect rapid changes in dFNC.

NEW METHOD

Here we first calculate the gradients of each time series pair and use the magnitude of these gradients to calculate weighted average of shared trajectory (WAST) as a new estimator for dFNC.

RESULTS

Using WAST to compare healthy control and schizophrenia patients using a large dataset, we show disconnectivity between different regions associated with schizophrenia. In addition, WAST results reveals patients with schizophrenia stay longer in a connectivity state with negative connectivity between motor and sensory regions than do healthy controls.

COMPARISON WITH EXISTING METHODS

We compare WAST with SWPC and multiplication of temporal derivatives (MTD) using different simulation scenarios. We show that WAST enables us to detect very rapid changes in dFNC (undetected by SWPC) while MTD performance is generally lower.

CONCLUSIONS

As large window sizes are unable to detect short states, using shorter window size is desirable if the estimator is robust enough. We provide evidence that WAST requires fewer samples (compared to SWPC) to reach a robust estimation. As a result, we were able to identify rapidly varying dFNC patterns undetected by SWPC while still being able to robustly estimate slower dFNC patterns.

Classification of Major Depressive Disorder from Resting-State fMRI

Major Depressive Disorder (MDD) is a very serious mental illness that can affect the daily lives of patients. Accurate diagnosis of this disorder is necessary for planning individualized treatment. However, diagnosing MDD requires the clinicians to personally interview the subjects and rate the symptoms based on Diagnostic and Statistical Manual of Mental Disorders (DSM), which can be very time consuming. Discovering quantifiable signals and biomarkers associated with MDD using functional magnetic resonance imaging (fMRI) scans of patients have the potential to assist the clinicians in their assessment. This paper explores the use of resting-state functional connectivity and network features to classify MDD vs. healthy subjects. For each subject, mean time-series are extracted from 85 brain regions and they are decomposed to 4-frequency bands. Mean time-series for each of the frequency bands are utilized to compute the Pearson correlation and network characteristics. Features are selected separately from correlation and network characteristics using Minimum Redundancy Maximum Relevance (mRMR) to create the final classifier. The proposed scheme achieves 79% accuracy (65 out of 82 subjects classified correctly) with 86% sensitivity (42 out of 49 MDD subjects identified correctly) and 70% specificity (23 out of 33 controls identified correctly) using leave-one-out classification with in-fold feature selection. Pearson correlation had the highest discrimination in band 0.015-0.03 Hz and network based features had the highest discrimination in band 0.03-0.06 Hz for distinguishing MDD vs. healthy subjects.

Cytokines and Cortisol - predictors of treatment response to corticosteroids in community-acquired pneumonia?

BACKGROUND

A previous study found community-acquired pneumonia (CAP) patients with imbalance of high inflammation and discordantly low cortisol levels to benefit most from adjunctive corticosteroid treatment. Our aim was to validate this hypothesis in a preplanned secondary analysis of the randomized controlled STEP trial.

METHODS

Patients included in the STEP trial receiving 50 mg prednisone or placebo for 5 days were categorized based on pro-inflammatory cytokines (Interleukin-6/8/MCP-1), CRP and cortisol levels on admission into four groups (high/low inflammation and high/low cortisol). The primary combined end-point was mortality or ICU admission within 30 days.

RESULTS

In total, 632 patients (315 prednisone, 317 placebo) were included in this analysis. Prednisone did not significantly reduce the risk for the primary end-point in patients with high cytokines/low cortisol and in any other subgroups. However, we noted some differences in the strength of corticosteroid effect in the different subgroups with stronger effects in patients with high cytokines [OR 0.44 (0.10,1.72)] compared to patients with low cytokines [OR 0.68 (0.30,1.5)] (P-interaction = 0.600). The effects did not differ according to cortisol levels.

CONCLUSION

The imbalance of high inflammation state and low cortisol levels did not predict treatment response to corticosteroids in patients with CAP. However, in line to previous research, inflammation as measured by cytokine levels irrespective of cortisol tended to predict treatment response to corticosteroids in CAP. Whether this concept may help to personalize corticosteroids to patients most likely benefitting from this treatment needs to be tested in future intervention trials.

Safety and Feasibility of Transcranial Magnetic Stimulation as an Exploratory Assessment of Corticospinal Connectivity in Infants After Perinatal Brain Injury: An Observational Study

BACKGROUND

Perinatal brain injuries often impact the corticospinal system, leading to motor impairment and cerebral palsy. Although transcranial magnetic stimulation (TMS) has been widely used to study corticospinal connectivity in adults and older children, similar studies of young infants are limited.

OBJECTIVES

The objective was to establish the safety and feasibility of advanced TMS assessments of the corticospinal connectivity of young infants with perinatal brain injury.

DESIGN

This was a pilot, cross-sectional study of 3- to 12-month-old (corrected age) infants with perinatal stroke or intracranial hemorrhage.

METHODS

Six participants (2 term, 4 preterm) were assessed with stereotactic neuronavigation-guided TMS. Single-pulse TMS was applied to each hemisphere and responses were recorded simultaneously from both upper limbs. During data collection, vital signs and stress responses were measured to assess safety. Developmental motor outcomes were evaluated using the General Movements Assessment and Bayley Scales of Infant and Toddler Development (3rd edition). A clinical diagnosis of cerebral palsy was recorded, if available.

RESULTS

No adverse events occurred during TMS testing. All sessions were well tolerated. Contralateral motor evoked responses were detected in 4 of 6 participants. Both contralateral and ipsilateral responses were observed in 2 of 6 participants.

LIMITATIONS

TMS responses were not obtained in all participants. This could be related to the location of brain injury or developmental stage of the corticospinal system controlling the wrist flexor muscle group from which responses were recorded.

CONCLUSIONS

This study provides a summary of the framework for performing novel TMS assessments in infants with perinatal brain injury. Implementing this approach to measure corticospinal connectivity in hypothesis-driven studies in young infants appears to be justified. Such studies could inform the characterization of corticospinal development and the neural mechanisms driving recovery following early interventions.

Brain structural thickness and resting state autonomic function in adolescents with major depression

Major depressive disorder (MDD) has been associated with abnormalities in cortical thickness and autonomic function. Adolescence is a time notable for brain development and MDD onset. In healthy adolescents, greater resting state vagal activity (RVA) is associated with lower cortical thickness. The relationship between brain structural thickness and RVA in adolescents with MDD has not previously been studied. This secondary analysis drew on a sample of 37 non-depressed controls and 53 adolescents with MDD. Resting state heart rate and two indices of RVA (HF-HRV and RMSSD) were recorded during a neuroimaging session. Cortical thickness within fronto-limbic regions of interest was measured using Freesurfer analysis of T1-weighted high-resolution structural images. Self-reports of depression severity showed a significant interaction with cortical thickness of the right insula in predicting RMSSD [t = 2.22, P=0.030, β = 5.44; model fit of the interaction term as indicated by the ‘Bayes Factor’ (BF): 7.58] and HF-HRV (t = 2.09, P=0.041, β = 4.72; BF: 7.94). Clinician ratings of depression severity showed further interactions. Findings underscore the important relationships between RVA and cortical development, suggesting two possible explanations: (i) in adolescent MDD, greater fronto-limbic thickness is compensatory for deficits in autonomic regulation or (ii) increased autonomic arousal results in delayed fronto-limbic maturation. Longitudinal research is necessary to further clarify the nature of the relationship between autonomic functioning and cortical development.

Hyponatremia and activation of vasopressin secretion are both independently associated with 30-day mortality: results of a multicenter, observational study

BACKGROUND

Hyponatremia is a common feature of acute illness and associated with increased mortality. This may be explained by a stress-mediated activation of the vasopressin system with an increase in free-water reabsorption.

OBJECTIVES

To investigate whether the association between hyponatremia and mortality could be explained by activation of the vasopressin system.

METHODS

We prospectively enrolled adult, medical patients seeking emergency care in three centres in Switzerland, France and the United States. We investigated associations between admission plasma sodium and copeptin, a stable portion of the vasopressin-precursor peptide, with 30-day mortality. We performed uni- and multivariate regression analysis.

RESULTS

Of 6962 included patients, 18% had hyponatremia (sodium ≤135 mmol L^-1 ), which doubled their risk for mortality compared to patients with normonatremia (8.3% vs. 3.8%). This association was confirmed in a multivariate-adjusted logistic regression analysis [adjusted odds ratio (OR) 1.47, 95% CI 1.12-1.93, P = 0.005]. Vasopressin levels, mirrored by copeptin, were also increased in nonsurvivors and strongly associated with mortality (adjusted OR 3.42, 95% CI 2.76-4.25, P < 0.001). The association between hyponatremia and mortality remained unchanged when adding copeptin levels to the regression model (fully adjusted OR 1.53, 95% CI 1.16-2.00, P = 0.002).

CONCLUSION

This prospective study including medical patients upon emergency room admission found hyponatremia as well as an activation of the vasopressin system to be independently associated with mortality. This suggests that stress- and vasopressin-independent mechanisms are responsible for the association of low sodium levels with mortality.

Detection of thoracic vascular structures by electrical impedance tomography: a systematic assessment of prominence peak analysis of impedance changes

OBJECTIVE

Electrical impedance tomography (EIT) is a non-invasive and radiation-free bedside monitoring technology, primarily used to monitor lung function. First experimental data shows that the descending aorta can be detected at different thoracic heights and might allow the assessment of central hemodynamics, i.e. stroke volume and pulse transit time.

APPROACH

First, the feasibility of localizing small non-conductive objects within a saline phantom model was evaluated. Second, this result was utilized for the detection of the aorta by EIT in ten anesthetized pigs with comparison to thoracic computer tomography (CT). Two EIT belts were placed at different thoracic positions and a bolus of hypertonic saline (10 ml, 20%) was administered into the ascending aorta while EIT data were recorded. EIT images were reconstructed using the GREIT model, based on the individual's thoracic contours. The resulting EIT images were analyzed pixel by pixel to identify the aortic pixel, in which the bolus caused the highest transient impedance peak in time.

MAIN RESULTS

In the phantom, small objects could be located at each position with a maximal deviation of 0.71 cm. In vivo, no significant differences between the aorta position measured by EIT and the anatomical aorta location were obtained for both measurement planes if the search was restricted to the dorsal thoracic region of interest (ROIs).

SIGNIFICANCE

It is possible to detect the descending aorta at different thoracic levels by EIT using an intra-aortic bolus of hypertonic saline. No significant differences in the position of the descending aorta on EIT images compared to CT images were obtained for both EIT belts.

Frequency of use and acceptability of clinical prediction rules for pulmonary embolism among Swiss general internal medicine residents

INTRODUCTION

Whether clinical prediction rules for pulmonary embolism are accepted and used among general internal medicine residents remains uncertain. We therefore evaluated the frequency of use and acceptability of the Revised Geneva Score (RGS) and the Pulmonary Embolism Severity Index (PESI), and explored which factors were associated with rule use.

MATERIALS/METHODS

In an online survey among general internal medicine residents from 10 Swiss hospitals, we assessed rule acceptability using the Ottawa Acceptability of Decision Rules Instrument (OADRI) and explored the association between physician and training-related factors and rule use using mixed logistic regression models.

RESULTS

The response rate was 50.4% (433/859). Overall, 61% and 36% of the residents reported that they always or regularly use the RGS and the PESI, respectively. The mean overall OADRI score was 4.3 (scale 0-6) for the RGS and 4.1 for the PESI, indicating a good acceptability. Rule acceptability (odds ratio [OR] 6.19 per point, 95% confidence interval [CI] 3.64-10.51), prior training in emergency medicine (OR 5.14, CI 2.20-12.01), and availability of internal guidelines recommending RGS use (OR 4.25, CI 2.15-8.43) were associated with RGS use. Rule acceptability (OR 6.43 per point, CI 4.17-9.92) and rule taught at medical school (OR 2.06, CI 1.24-3.43) were associated with PESI use.

CONCLUSIONS

The RGS was more frequently used than the PESI. Both rules were considered acceptable. Rule acceptability, prior training in emergency medicine, availability of internal guidelines, and rule taught at medical school were associated with rule use and represent potential targets for quality improvement interventions.

The association of admission hyperglycaemia and adverse clinical outcome in medical emergencies: the multinational, prospective, observational TRIAGE study

AIMS

The clinical relevance of hyperglycaemia in an emergency department population remains incompletely understood. We investigated the association between admission blood glucose levels and adverse clinical outcomes in a large emergency department cohort.

METHODS

We prospectively enrolled 7132 adult medical patients seeking emergency department care in three tertiary care hospitals in Switzerland, France and the USA. We used adjusted multivariable logistic regression models to examine the association between admission blood glucose levels and 30-day mortality, as well as adverse clinical course stratified by pre-existing diabetes and principal medical diagnoses.

RESULTS

In 6044 people without diabetes (84.7%), severe hyperglycaemia, defined as a glucose level of > 11.1 mmol/l (200 mg/dl), was associated with a doubling in the risk of 30-day mortality [adjusted odds ratio (OR) 1.9; 95% confidence interval (95% CI), 1.1 to 3.3; P = 0.018] and a three-fold increase in the risk of intensive care unit admission (adjusted OR 3.0; 95% CI, 1.9 to 4.9; P < 0.001). These associations were similar among different diagnoses. In the population with diabetes (n = 1088), no association with 30-day mortality was found (adjusted OR 1.0; 95% CI, 0.6 to 1.8; P for interaction = 0.001), whereas the association with intensive care unit admission was weaker (adjusted OR 2.4; 95% CI, 1.5 to 4.1; P for interaction = 0.011). Overall 30-day mortality was higher in those with diabetes than in those without (6.1 vs. 4.4%, P = 0.015).

CONCLUSIONS

In this large medical emergency department patient cohort, admission hyperglycaemia was strongly associated with adverse clinical course in people without diabetes. (Clinical Trial Registry No: NCT01768494).

The impact of hyperhidrosis on patients' daily life and quality of life: a qualitative investigation

BACKGROUND

An understanding of the daily life impacts of hyperhidrosis and how patients deal with them, based on qualitative research, is lacking. This study investigated the impact of hyperhidrosis on the daily life of patients using a mix of qualitative research methods.

METHODS

Participants were recruited through hyperhidrosis patient support groups such as the Hyperhidrosis Support Group UK. Data were collected using focus groups, interviews and online surveys. A grounded theory approach was used in the analysis of data transcripts. Data were collected from 71 participants, out of an initial 100 individuals recruited.

RESULTS

Seventeen major themes capturing the impacts of hyperhidrosis were identified; these covered all areas of life including daily life, psychological well-being, social life, professional /school life, dealing with hyperhidrosis, unmet health care needs and physical impact.

CONCLUSIONS

Psychosocial impacts are central to the overall impacts of hyperhidrosis, cutting across and underlying the limitations experienced in other areas of life.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Comparison of non-invasive MRI measurements of cerebral blood flow in a large multisite cohort

Arterial spin labeling and phase contrast magnetic resonance imaging provide independent non-invasive methods for measuring cerebral blood flow. We compared global cerebral blood flow measurements obtained using pseudo-continuous arterial spin labeling and phase contrast in 436 middle-aged subjects acquired at two sites in the NHLBI CARDIA multisite study. Cerebral blood flow measured by phase contrast (CBFPC: 55.76 ± 12.05 ml/100 g/min) was systematically higher (p < 0.001) and more variable than cerebral blood flow measured by pseudo-continuous arterial spin labeling (CBFPCASL: 47.70 ± 9.75). The correlation between global cerebral blood flow values obtained from the two modalities was 0.59 (p < 0.001), explaining less than half of the observed variance in cerebral blood flow estimates. Well-established correlations of global cerebral blood flow with age and sex were similarly observed in both CBFPCASL and CBFPC CBFPC also demonstrated statistically significant site differences, whereas no such differences were observed in CBFPCASL No consistent velocity-dependent effects on pseudo-continuous arterial spin labeling were observed, suggesting that pseudo-continuous labeling efficiency does not vary substantially across typical adult carotid and vertebral velocities, as has previously been suggested.

CONCLUSIONS

Although CBFPCASL and CBFPC values show substantial similarity across the entire cohort, these data do not support calibration of CBFPCASL using CBFPC in individual subjects. The wide-ranging cerebral blood flow values obtained by both methods suggest that cerebral blood flow values are highly variable in the general population.

Treatment of type I ROP with intravitreal bevacizumab or laser photocoagulation according to retinal zone

AIMS

To investigate the outcome of intravitreal bevacizumab (IVB) compared with laser photocoagulation in type I retinopathy of prematurity (ROP).

METHODS

Case records of 54 consecutive very low birth weight (VLBW) infants with type I ROP (posterior ROP, n=33; peripheral zone II, n=21) who were treated either with IVB (n=37) or laser photocoagulation (n=17) between 2011 and 2015 were retrospectively evaluated.

RESULTS

Patients with posterior ROP displayed significantly faster regression of active ROP within 12 days (range 9-15 days) if treated with IVB compared with laser photocoagulation, where active ROP regressed within 57 days (range 28-63 days) (p>0.001). No difference was observed in peripheral zone II.Five of seven patients (12%) who developed a recurrence in both eyes after IVB required additional laser photocoagulation within a mean of 12.7 weeks (11.3-15.6 weeks) after the previous treatment. After laser photocoagulation one patient with posterior ROP developed macular dragging and another patient developed a temporary exudative retinal detachment in both eyes. 12 months after treatment the spherical equivalent was not statistically significant different between IVB and laser photocoagulation in posterior ROP patients. However, IVB lead to a significant lower spherical equivalent in infants with posterior ROP (+0.37 dioptres, range -0.5 to +1.88 dioptres) compared with peripheral zone II (+3.0 dioptres range +2.0 to +4.0 dioptres, p<0.001).

CONCLUSIONS

IVB leads to faster regression of active ROP in infants with posterior ROP compared with laser photocoagulation. Spherical equivalent after 12 months was comparable in those treated with IVB and laser photocoagulation, but it was significantly lower in posterior ROP than in peripheral zone II.

Network analysis of functional brain connectivity in borderline personality disorder using resting-state fMRI

Borderline personality disorder (BPD) is associated with symptoms such as affect dysregulation, impaired sense of self, and self-harm behaviors. Neuroimaging research on BPD has revealed structural and functional abnormalities in specific brain regions and connections. However, little is known about the topological organizations of brain networks in BPD. We collected resting-state functional magnetic resonance imaging (fMRI) data from 20 patients with BPD and 10 healthy controls, and constructed frequency-specific functional brain networks by correlating wavelet-filtered fMRI signals from 82 cortical and subcortical regions. We employed graph-theory based complex network analysis to investigate the topological properties of the brain networks, and employed network-based statistic to identify functional dysconnections in patients. In the 0.03–0.06 Hz frequency band, compared to controls, patients with BPD showed significantly larger measures of global network topology, including the size of largest connected graph component, clustering coefficient, small-worldness, and local efficiency, indicating increased local cliquishness of the functional brain network. Compared to controls, patients showed lower nodal centrality at several hub nodes but greater centrality at several non-hub nodes in the network. Furthermore, an interconnected subnetwork in 0.03–0.06 Hz frequency band was identified that showed significantly lower connectivity in patients. The links in the subnetwork were mainly long-distance connections between regions located at different lobes; and the mean connectivity of this subnetwork was negatively correlated with the increased global topology measures. Lastly, the key network measures showed high correlations with several clinical symptom scores, and classified BPD patients against healthy controls with high accuracy based on linear discriminant analysis. The abnormal topological properties and connectivity found in this study may add new knowledge to the current understanding of functional brain networks in BPD. However, due to limitation of small sample sizes, the results of the current study should be viewed as exploratory and need to be validated on large samples in future works.

•

We analyzed the topology and connectivity of functional brain networks in BPD.

•

Patients with BPD showed altered small-world properties and network efficiency.

•

Patients with BPD showed altered nodal centrality at specific brain regions.

•

An interconnected subnetwork showed significantly lower connectivity in BPD.

•

Key network measures were correlated with clinical symptom scores.

Neuropsychological profile in adult schizophrenia measured with the CMINDS

Schizophrenia neurocognitive domain profiles are predominantly based on paper-and-pencil batteries. This study presents the first schizophrenia domain profile based on the Computerized Multiphasic Interactive Neurocognitive System (CMINDS(®)). Neurocognitive domain z-scores were computed from computerized neuropsychological tests, similar to those in the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB), administered to 175 patients with schizophrenia and 169 demographically similar healthy volunteers. The schizophrenia domain profile order by effect size was Speed of Processing (d=-1.14), Attention/Vigilance (d=-1.04), Working Memory (d=-1.03), Verbal Learning (d=-1.02), Visual Learning (d=-0.91), and Reasoning/Problem Solving (d=-0.67). There were no significant group by sex interactions, but overall women, compared to men, showed advantages on Attention/Vigilance, Verbal Learning, and Visual Learning compared to Reasoning/Problem Solving on which men showed an advantage over women. The CMINDS can readily be employed in the assessment of cognitive deficits in neuropsychiatric disorders; particularly in large-scale studies that may benefit most from electronic data capture.

Synergistic effect of combined transcranial direct current stimulation/constraint-induced movement therapy in children and young adults with hemiparesis: study protocol

Background

Perinatal stroke occurs in more than 1 in 2,500 live births and resultant congenital hemiparesis necessitates investigation into interventions which may improve long-term function and decreased burden of care beyond current therapies (http://www.cdc.gov/ncbddd/cp/data.html). Constraint-Induced Movement Therapy (CIMT) is recognized as an effective hemiparesis rehabilitation intervention . Transcranial direct current stimulation as an adjunct treatment to CIMT may potentiate neuroplastic responses and improve motor function. The methodology of a clinical trial in children designed as a placebo-controlled, serial –session, non-invasive brain stimulation trial incorporating CIMT is described here. The primary hypotheses are 1) that no serious adverse events will occur in children receiving non-invasive brain stimulation and 2) that children in the stimulation intervention group will show significant improvements in hand motor function compared to children in the placebo stimulation control group.

Methods/design

A randomized, controlled, double-blinded clinical trial. Twenty children and/or young adults (ages 8–21) with congenital hemiparesis, will be enrolled. The intervention group will receive ten 2-hour sessions of transcranial direct current stimulation combined with constraint-induced movement therapy and the control group will receive sham stimulation with CIMT. The primary outcome measure is safety assessment of transcranial direct current stimulation by physician evaluation, vital sign monitoring and symptom reports. Additionally, hand function will be evaluated using the Assisting Hand Assessment, grip strength and assessment of goals using the Canadian Occupational Performance Measure. Neuroimaging will confirm diagnoses, corticospinal tract integrity and cortical activation. Motor cortical excitability will also be examined using transcranial magnetic stimulation techniques.

Discussion

Combining non-invasive brain stimulation and CIMT interventions has the potential to improve motor function in children with congenital hemiparesis beyond each intervention independently. Such a combined intervention has the potential to benefit an individual throughout their lifetime.

Trial registration

Clinicaltrials.gov, NCT02250092Registered 18 September 2014

Clinical risk scores and blood biomarkers as predictors of long-term outcome in patients with community-acquired pneumonia: a 6-year prospective follow-up study

OBJECTIVE

Prediction of long-term outcomes in patients with community-acquired pneumonia (CAP) is incompletely understood. We investigated the value of clinical risk scores [pneumonia severity index (PSI) and CURB-65] (Confusion, Urea, Respiratory rate, Blood Pressure, Age >65 years) and blood biomarkers of different physiopathological pathways in predicting long-term survival in a well-characterized cohort of patients with CAP enrolled in an antibiotic stewardship trial.

DESIGN, SETTING AND SUBJECTS

Patients admitted with CAP to six medical centres in Switzerland were prospectively followed for 6 years. Cox regression models and area under the receiver operating characteristics curve (AUC) were used to investigate associations between initial risk assessment and all-cause mortality.

MAIN OUTCOME MEASURE

All-cause mortality during a 6-year follow-up period.

RESULTS

Six-year mortality in the present cohort (median age 73 years) was 45.1% [95% confidence interval (CI) 41.8-48.3%]. Initial PSI and CURB-65 scores both had excellent long-term prognostic accuracy, with a stepwise increase in mortality per risk class. The hazard ratios (95% CI) of the highest PSI and CURB-65 classes (reference: lowest class) were 38.0 (14.0-103.0) and 7.8 (2.2-14.5), respectively, after 6 years. The addition of inflammatory (pro-adrenomedullin) and cardiac (pro-atrial natriuretic peptide) blood biomarkers measured upon hospital admission further improved the prognostic capabilities of the PSI (AUC increase from 0.79 to 0.83; P < 0.0001) and the CURB-65 score (AUC increase from 0.73 to 0.80; P < 0.001).

CONCLUSION

Risk assessment using clinical scores allowed accurate long-term prognostication, which was further improved by the addition of two inflammatory (pro-adrenomedullin) and cardiac (pro-atrial natriuretic peptide) blood biomarkers. These data provide a rationale for a more risk-adapted, 'personalized' strategy for long-term management of patients with CAP.

Separated response function ratios in exclusive, forward π(±) electroproduction

The study of exclusive π(±) electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio RL=σL(π-)/σL(π+) is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of RT=σT(π-)/σT(π+) from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to perturbative QCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive π(±) electroproduction on the deuteron at central Q(2) values of 0.6, 1.0, 1.6  GeV(2) at W=1.95  GeV, and Q(2)=2.45  GeV(2) at W=2.22  GeV. Here, we present the L and T cross sections, with emphasis on RL and RT, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for RT are consistent with a transition between pion knockout and quark knockout mechanisms.

A multi-scanner study of subcortical brain volume abnormalities in schizophrenia

Schizophrenia patients show significant subcortical brain abnormalities. We examined these abnormalities using automated image analysis software and provide effect size estimates for prospective multi-scanner schizophrenia studies. Subcortical and intracranial volumes were obtained using FreeSurfer 5.0.0 from high-resolution structural imaging scans from 186 schizophrenia patients (mean age±S.D.=38.9±11.6, 78% males) and 176 demographically similar controls (mean age±S.D.=37.5±11.2, 72% males). Scans were acquired from seven 3-Tesla scanners. Univariate mixed model regression analyses compared between-group volume differences. Weighted mean effect sizes (and number of subjects needed for 80% power at α=0.05) were computed based on the individual single site studies as well as on the overall multi-site study. Schizophrenia patients have significantly smaller intracranial, amygdala, and hippocampus volumes and larger lateral ventricle, putamen and pallidum volumes compared with healthy volunteers. Weighted mean effect sizes based on single site studies were generally larger than effect sizes computed based on analysis of the overall multi-site sample. Prospectively collected structural imaging data can be combined across sites to increase statistical power for meaningful group comparisons. Even when using similar scan protocols at each scanner, some between-site variance remains. The multi-scanner effect sizes provided by this study should help in the design of future multi-scanner schizophrenia imaging studies.