MIR137 polygenic risk for schizophrenia and ephrin-regulated pathway: Role in lateral ventricles and corpus callosum volume

Background/Objective. Enlarged lateral ventricle (LV) volume and decreased volume in the corpus callosum (CC) are hallmarks of schizophrenia (SZ). We previously showed an inverse correlation between LV and CC volumes in SZ, with global functioning decreasing with increased LV volume. This study investigates the relationship between LV volume, CC abnormalities, and the microRNA MIR137 and its regulated genes in SZ, because of MIR137's essential role in neurodevelopment. Methods. Participants were 1224 SZ probands and 1466 unaffected controls from the GENUS Consortium. Brain MRI scans, genotype, and clinical data were harmonized across cohorts and employed in the analyses. Results. Increased LV volumes and decreased CC central, mid-anterior, and mid-posterior volumes were observed in SZ probands. The MIR137-regulated ephrin pathway was significantly associated with CC:LV ratio, explaining a significant proportion (3.42 %) of CC:LV variance, and more than for LV and CC separately. Other pathways explained variance in either CC or LV, but not both. CC:LV ratio was also positively correlated with Global Assessment of Functioning, supporting previous subsample findings. SNP-based heritability estimates were higher for CC central:LV ratio (0.79) compared to CC or LV separately. Discussion. Our results indicate that the CC:LV ratio is highly heritable, influenced in part by variation in the MIR137-regulated ephrin pathway. Findings suggest that the CC:LV ratio may be a risk indicator in SZ that correlates with global functioning.

Carepath for overcoming psychosis early (COPE): first 5 years of clinical operation and prospective research in the Cavan-Monaghan early intervention service

OBJECTIVES

As Ireland confronts the many challenges of broadening the introduction of early intervention services (EIS) for first episode psychosis (FEP) as national policy, this article describes Carepath for Overcoming Psychosis Early (COPE), the EIS of Cavan-Monaghan Mental Health Service, and presents prospective research findings during its first 5 years of operation.

METHODS

COPE was launched as a rural EIS with an embedded research protocol in early 2012, following an education programme for general practitioners (GPs). Here, operational activities are documented and research findings presented through to late 2016.

RESULTS

During this period, 115 instances of FEP were incepted into COPE, 70.4% via their GP and 29.6% via the Emergency Department. The annual rate of inception was 24.8/100,000 of population aged > 15 years and was 2.1-fold more common among men than women. Mean duration of untreated psychosis was 5.7 months and median time from first psychotic presentation to initiation of antipsychotic treatment was zero days. Assessments of psychopathology, neuropsychology, neurology, premorbid functioning, quality of life, insight, and functionality compared across 10 DSM-IV psychotic diagnoses made at six months following presentation indicated minimal differences between them, other than more prominent negative symptoms in schizophrenia and more prominent mania in bipolar disorder.

CONCLUSIONS

COPE illustrates the actuality of introducing and the challenges of operating a rural EIS for FEP. Prospective follow-up studies of the 5-year COPE cohort should inform on the effectiveness of this EIS model in relation to long-term outcome in psychotic illness across what appear to be arbitrary diagnostic boundaries at FEP.

Reduction in Antibiotic Delivery Time Following Improving Pediatric Sepsis Outcomes Quality Improvement Initiative at a Major Children's Hospital

OBJECTIVE

Sepsis causes morbidity and mortality in pediatric patients, but timely antibiotic administration can improve sepsis outcomes. The pharmacy department can affect the time from order to delivery of antibiotics. By evaluating the pharmacy process, this study aimed to decrease the time from antibiotic order to delivery to within 45 minutes.

METHODS

All antibiotic orders placed following a positive sepsis screen for acute care patients at a freestanding children's hospital from April 1, 2019, to December 31, 2019, were reviewed. Lean Six Sigma methodology including process mapping was used to identify and implement improvements, including educational interventions for providers. Outcome measures included time from antibiotic order placement to delivery and to administration. Additional assessment of process measures included evaluation of order priority, PowerPlan (an internally created order set) use, and delivery method.

RESULTS

Ninety-eight antibiotic orders for 85 patients were evaluated. In an individual chart of antibiotic delivery time, a trend towards faster delivery time was observed after interventions. Stat orders (40.5 minutes [IQR, 19.5-48]) were delivered more quickly than routine orders (51 minutes [IQR, 45-65]; p < 0.001). Orders using the PowerPlan (20.5 minutes [IQR, 18.5-38]) were delivered more quickly than those that did not (47 minutes [IQR, 34-64]; p < 0.01). Shorter time to administration was observed with pneumatic tube delivery (41 minutes [IQR, 20-50]) than with direct delivery to a health care provider (51 minutes [IQR, 31-83]; p < 0.05) or to the automated dispensing cabinet's refrigerator (47 minutes [IQR, 41-62]; p < 0.0001).

CONCLUSIONS

Multifactorial coordinated interventions within the pharmacy department improve medication delivery time for pediatric sepsis antibiotic orders.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

POS1122 ULTRASOUND GUIDED INJECTIONS OF HYADD4 FOR KNEE OSTEOARTHRITIS IMPROVES PAIN AND FUNCTIONAL OUTCOMES AT 3 AND 6 MONTHS WITHOUT CHANGES IN SYNOVIAL FLUID VOLUMES

Background

Prior studies have demonstrated improved accuracy and efficacy when Intra-articular (IA) therapeutics are injected using ultrasound (US) guidance. There is also growing evidence that many patients with knee osteoarthritis (OA) exhibit a pro-inflammatory catabolic synovial fluid (SF) profile. However, it is not known if temporary clinical improvement in pain and function after IA Hyaluronic acid (HA) injections is associated with changes in SF volumes.

Objectives

The purpose of this study was to determine if IA HA injections delivered using US directed needle visualization with an external pneumatic compression device would result in improved clinical outcomes for knee OA at 3 and 6 months, and if this was associated with a reduction in the amount of knee synovial fluid (SF) measured on US.

Methods

49 eligible subjects with symptomatic Knee OA, BMI < 40 and KL radiographic rating of II or III OA were consented for this open label prospective IRB approved Investigator Initiated SF OA biomarker study (HS 3179, NCT 04093232). All standing radiographs were reviewed by a fellowship-trained MSK radiologist. 36 subjects had adequate aspirated SF volumes of > 500 mcl for biomarker analysis and therefore were eligible to receive two IA injections of HYADD4, 24 mg/3ml (Fidia Farmaceutici S.p.A. Italy) 7 days apart by a MSK US certified Rheumatologist. An external pneumatic compression device and US visualized needle insertion ensured injections were delivered into the intra-synovial space. Despite COVID-19 restrictions, 34 patients (17 women and 17 men) between 35 and 78 years of age returned for 3 month evaluations and 30 had evaluations at 6 months. The following clinical variables were measured: Western Ontario and McMaster Universities Index (WOMAC) total scores, Visual Analog Pain Scale (VAS, 0-10), PCS scores on the SF-36 health survey questionnaires (physical function/bodily pain and general health), 6-minute walking distance in meters (6 MWD), and measured SF depth before and after an external pneumatic compression device was inflated to 100 mmHg to facilitate aspiration by increasing available SF volumes under positive presure. The SF depth was measured on the recorded US image (GE logiq e) as the largest anechoic region selected for aspiration on either the lateral (n= 30) or medial (n=4) compartment. SF and simultaneous peripheral blood samples were centrifuged and cryopreserved at -80 o C within 45 minutes of aspiration for future analysis. Statistical differences between baseline values compared to those levels at 3 and 6 months were determined using a paired ANOVA test with p <0.05 significance.

Results

Improvements over baseline values were observed at 3 and 6 months respectively, after IA HA injections in WOMAC (40%, 40%), VAS (45%, 51%) and PCS (15%, 18%) all p< 0.0001. The 6 WWD improved by 7 % at 3 months (p< 0.007) but was not statistically improved at 6 months. US measured SF depth at baseline was 3.2 ± 2.2 mm before inflation and 6.4 + 3.7 mm after inflation of the pneumatic external compressioin device but statistical differences in SF depth were not observed at 3 and 6 months.

Conclusion

Despite improvements in WOMAC, VAS scores, and PCS scores on the SF 36 at 3 and 6 months after US guided knee injections with an HA product, a statistically significant reduction in the amount of US measured SF was not observed. The 6 MWD improved at 3 months but was not statistically different from the baseline distance by 6 months. IA injections using US needle visualization confirmed that the product was delivered into the synovial space with 100 % accuracy which might have resulted in improved efficacy results in this study compared to prior IA HA studies injected without US or using different HA products. In the future, we hope SF biomarkers may identify which individual OA patients will likely achieve the greatest benefit with IA HA injections and to determine if this is associated with a reduction in catabolic pro-inflammatory proteins.

Disclosure of Interests

richard Meehan Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. I was the PI., Mary Gill Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. As the study coordinator she received salary support, Eric Hoffman Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. As a biomedical engineer consultant he received some compensation for his work., Molly Wolf Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. As the Immunology laboratory supervisor she received support from this grant for sample processing and analysis., Isabelle Amigues Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. As a Rheumatologist who performed some of the aspirations and injections she did receive some very small salary support from this grant., Liudmila (Mila) Kastsianok Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. As a Rheumatologist who performed some of the aspirations and injections she did receive some very small salary support from this grant., Elizabeth Regan Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. As a orthopedic surgeon and immunologists she did receive some very small salary support from this grant., James Crooks Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. As our biostatistician for this project he did receive some support from this grant for statistical analysis and consultation., Gregory Czuczman: None declared, claire Coeshott Consultant of: She was ben an employee for pharmaceutical companies in the past unrelated to this project and has no relationship in the past with Fidia who funded the study., Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. As the director of the ADx immunology labs where this samples are processed her staff received some compensation for sample handling and biomarker analysis. She did not receive any salary support., Vijaya Knight Grant/research support from: This grant was funded by Fidia Pharmaceutici and Fidia Pharma USA as an Investigator Initiated grant for synovial fluid based biomarker research in osteoarthritis. As an Immunologists and prior director of the ADx immunology labs when the project started in 2019 her staff performed sample processing and testing and they received support from this grant by Dr Knight did not receive and salary support or direct compensation for her consultation expertise.

In Vivo Reflectance Confocal Microscopy of Cutaneous Acute Graft-Versus-Host Disease: Concordance with Histopathology and Interobserver Reproducibility of a Glossary with Representative Images

BACKGROUND

The reliability to noninvasively identify features of inflammatory dermatoses by reflectance confocal microscopy (RCM) remains unknown. Lack of formal training among RCM readers can result in inconsistent assessments, limiting clinical utility. Specific consensus terminology with representative images is necessary to ensure consistent feature-level interpretation among RCM readers.

OBJECTIVES

(1) Develop a glossary with representative images of RCM features of cutaneous acute graft-versus-host disease (aGVHD) for consistent interpretation among observers, (2) assess the interobserver reproducibility among RCM readers using the glossary, and (3) determine the concordance between RCM and histopathology for aGVHD features.

METHODS

Through an iterative process of refinement and discussion among five international RCM experts, we developed a glossary with representative images of RCM features of aGVHD. From April to November 2018, patients suspected of aGVHD were imaged with RCM and subsequently biopsied. 17 lesions from 12 patients had clinically and pathologically confirmed cutaneous aGVHD. For each of these lesions, four dermatopathologists and four RCM readers independently evaluated the presence of aGVHD features in scanned histopathology slides and 1.5x1.5 mm RCM submosaics at 4 depths (blockstacks), respectively. RCM cases were adjudicated by a fifth RCM expert. Interobserver reproducibility was calculated by U statistic. Concordance between modalities was determined by fraction agreement.

RESULTS

We present a glossary with representative images of 18 aGVHD features by RCM. The average interobserver reproducibility among RCM readers (75%, confidence interval, CI: 71%-79%) did not differ significantly from dermatopathologists (80%, 76%-85%). The concordance between RCM and histopathology was 59%.

CONCLUSIONS

By using the glossary, the interobserver reproducibility among RCM readers was similar to the interobserver reproducibility among dermatopathologists. There was good concordance between RCM and histopathology to visualize aGVHD features. The implementation of RCM can now be advanced in a variety of inflammatory conditions with a validated glossary and representative image set.

Review: More effective linkages between science and policy are needed to minimize the negative environmental impacts of livestock production

Animals form an integral part of our planetary ecosystem but balance is critical to effective ecosystem functioning as demand for livestock products has increased, greater numbers of domesticated livestock have created an imbalance and hence had a negative impact on a number of ecosystem services which means that life as we know it will become unsustainable. Policies and technology advances have helped to manage the impact but more needs to be done. The aim of this paper is to highlight ways in which better knowledge of animal science, and other disciplines, can both harness technology and inform policy to work towards a sustainable balance between livestock and the environment. Effective policies require simple, quantifiable indicators against which to set targets and monitor progress. Indicators are clear for water pollution, but more complex for biodiversity. Hence, more progress has been made with the former. It is not yet possible to measure the impacts of changes in livestock management on greenhouse gas emissions per se at a farm level and progress has been slower, although new technologies are emerging. With respect to land use, the simple indicator of area has been used, but total area is oversimplistic. Our analysis of land suitability and use highlights a relatively overlooked role of livestock in acting as a 'buffer' to use by-products and grains which do not meet the standards for processing by industry during years of inclement weather, which in the past has provided an 'insurance policy' for farmers. Since extreme weather events are increasing in frequency with climate change, this role for livestock may be more important in future. The conclusions of the review with respect to strengthening the links between research and policy are i) to encourage animal scientists to identify the relevant environmental indicators, work with the cutting edge experts developing technologies to measure these cost-effectively and across a range of relevant livestock systems and ii) to work with the feed industry to optimize diets not just in terms of least cost financially but also least 'cost' in terms of global carbon flux and engage in dialogue with the food industry and policy makers on regulations for grain quality.

Research and innovation as a catalyst for food system transformation

BACKGROUND

Food systems are associated with severe and persistent problems worldwide. Governance approaches aiming to foster sustainable transformation of food systems face several challenges due to the complex nature of food systems.

SCOPE AND APPROACH

In this commentary we argue that addressing these governance challenges requires the development and adoption of novel research and innovation (R&I) approaches that will provide evidence to inform food system transformation and will serve as catalysts for change. We first elaborate on the complexity of food systems (transformation) and stress the need to move beyond traditional linear R&I approaches to be able to respond to persistent problems that affect food systems. Though integrated transdisciplinary approaches are promising, current R&I systems do not sufficiently support such endeavors. As such, we argue, we need strategies that trigger a double transformation - of food systems and of their R&I systems.

KEY FINDINGS AND CONCLUSIONS

Seizing the opportunities to transform R&I systems has implications for how research is done - pointing to the need for competence development among researchers, policy makers and society in general - and requires specific governance interventions that stimulate a systemic approach. Such interventions should foster transdisciplinary and transformative research agendas that stimulate portfolios of projects that will reinforce one another, and stimulate innovative experiments to shape conditions for systemic change. In short, a thorough rethinking of the role of R&I as well as how it is funded is a crucial step towards the development of the integrative policies that are necessary to engender systemic change - in the food system and beyond.

BDNF Val66Met polymorphism is associated with aggressive behavior in schizophrenia

Brain-derived neurotrophic factor (BDNF) gene variants may potentially influence behaviour. In order to test this hypothesis, we investigated the relationship between BDNF Val66Met polymorphism and aggressive behaviour in a population of schizophrenic patients. Our results showed that increased number of BDNF Met alleles was associated with increased aggressive behaviour.

Avoiding, diagnosing and treating well leg compartment syndrome after pelvic surgery

Background

Patients undergoing prolonged pelvic surgery may develop compartment syndrome of one or both lower limbs in the absence of direct trauma or pre‐existing vascular disease (well leg compartment syndrome). This condition may have devastating consequences for postoperative recovery, including loss of life or limb, and irreversible disability.

Methods

These guidelines represent the collaboration of a multidisciplinary group of colorectal, vascular and orthopaedic surgeons, acting on behalf of their specialty associations in the UK and Ireland. A systematic analysis of the available peer‐reviewed literature was undertaken to provide an evidence base from which these guidelines were developed.

Results

These guidelines encompass the risk factors (both patient‐ and procedure‐related), diagnosis and management of the condition. Key recommendations for the adoption of perioperative strategies to facilitate prevention and effective treatment of well leg compartment syndrome are presented.

Conclusion

All surgeons who carry out abdominopelvic surgical procedures should be aware of well leg compartment syndrome, and instigate policies within their own institution to reduce the risk of this potentially life‐changing complication.

Armed Conflict, Intimate Partner Violence, and Mental Distress of Women in Northeastern Uganda: A Mixed Methods Study

As global mental health research and programming proliferate, research that prioritizes women's voices and examines marginalized women's mental health outcomes in relation to exposure to violence at community and relational levels of the socioecological model is needed. In a mixed methods, transnational study, we examined armed conflict exposure, intimate partner violence (IPV), and depressive symptoms among 605 women in Northeastern Uganda. We used analysis of variance to test between groups of women who had experienced no IPV or armed conflict, IPV only, armed conflict only, and both; and linear regression to predict depressive symptoms. We used rapid ethnographic methods with a subsample (n = 21) to identify problem prioritization; and, to characterize women's mental health experiences, we conducted follow up in-depth interviews (n = 15), which we analyzed with grounded theory methods. Thirty percent of the sample met the cut-off for probable major depressive disorder; women exposed to both IPV and armed conflict had significantly higher rates of depression than all other groups. While women attributed psychological symptoms primarily to IPV exposure, both past-year IPV and exposure to armed conflict were significantly associated with depressive symptoms. Women identified socioeconomic neglect as having the most impact and described three interrelated mental health experiences that contribute to thoughts of escape, including escape through suicide. Policy efforts should be interprofessional, and specialists should collaborate to advance multi-pronged interventions and gender-informed implementation strategies for women's wellbeing.

Measurement of chronic pain in companion animals: Priorities for future research and development based on discussions from the Pain in Animals Workshop (PAW) 2017

The estimation of long-standing pain in companion animals through the measurement of different dimensions impacted by pain is a fundamental requirement if pain management, and pain therapeutic development, are to advance. Although pain management in veterinary medicine has advanced considerably in the last 20 years, there is much critical work to do in the area of measurement of chronic pain. To date, most work has centered on musculoskeletal pain, and has been focused around the measurement of limb use and the development of owner-completed questionnaires, or clinical metrology instruments (CMI). Recent areas of research have extended to developing measures of activity, sensory function (quantitative sensory testing; nociceptive withdrawal reflexes), and quality of life (QoL). Across all these areas, more data on validity are needed, and studies should be extended to other painful disease states. By necessity, assessing measurement tools requires testing in field studies, which incur considerable time and expense. Facilitating these studies could be optimized with a collaborative (industry, academia and private practice) approach, and the utility of the information produced from all field studies would be enhanced by full and transparent reporting and data sharing, including data already generated by industry in the form of studies submitted to the regulatory authorities.

Measurement of chronic pain in companion animals: Discussions from the Pain in Animals Workshop (PAW) 2017

In the face of increasing recognition and interest in treating chronic pain in companion animals, we struggle with a lack of therapeutic options. A significant barrier to the development of new therapeutics, or the critical evaluation of current therapies, is our inability to accurately measure chronic pain and its impact on companion animals. Over the last 20 years, much progress has been made in developing methods to measure chronic pain via subjective and objective methods - particularly in owner assessment tools and measurements of limb use and activity. Most work has been focused on chronic joint pain conditions, but there has been relatively little work in other areas of chronic pain, such as neuropathic and cancer pain. Although progress has been made, there is a considerable interest in improving our assessment of chronic pain, as evidenced by the multiple disciplines across industry, academia, and clinical practice from the veterinary and human medical fields that participated in the Pain in Animals Workshop held at the National Institutes of Health in 2017. This review is one product of that meeting and summarizes the current state of knowledge surrounding the measurement of chronic pain (musculoskeletal, cancer, neuropathic), and its impact, in cats and dogs.

Comparison of portable blood-warming devices under simulated pre-hospital conditions: a randomised in-vitro blood circuit study

Pre-hospital transfusion of blood products is a vital component of many advanced pre-hospital systems. Portable fluid warmers may be utilised to help prevent hypothermia, but the limits defined by manufacturers often do not reflect their clinical use. The primary aim of this randomised in-vitro study was to assess the warming performance of four portable blood warming devices (Thermal Angel, Hypotherm X LG, °M Warmer, Buddy Lite) against control at different clinically-relevant flow rates. The secondary aim was to assess haemolysis rates between devices at different flow rates. We assessed each of the four devices and the control, at flow rates of 50 ml.min^-1 , 100 ml.min^-1 and 200 ml.min^-1 , using a controlled perfusion circuit with multisite temperature monitoring. Free haemoglobin concentration, a marker of haemolysis, was measured at multiple points during each initial study run with spectrophotometry. At all flow rates, the four devices provided superior warming performance compared with the control (p < 0.001). Only the °M Warmer provided a substantial change in temperature at all flow rates (mean (95%CI) temperature change of 21.1 (19.8-22.4) °C, 20.4 (19.1-21.8) °C and 19.4 (17.7-21.1) °C at 50 ml.min^-1 , 100 ml.min^-1 and 200 ml.min^-1 , respectively). There was no association between warming and haemolysis with any device (p = 0.949) or flow rate (p = 0.169). Practical issues, which may be relevant to clinical use, also emerged during testing. Our results suggest that there were significant differences in the performance of portable blood warming devices used at flow rates encountered in clinical practice.

Accuracy of tele-consultation on management decisions of lesions suspect for melanoma using reflectance confocal microscopy as a stand-alone diagnostic tool

BACKGROUND

Diagnostic accuracy of reflectance confocal microscopy (RCM) as a stand-alone diagnostic tool for suspect skin lesions has not been extensively studied.

OBJECTIVE

Primary aim was to measure experts' accuracy in RCM-based management decisions. Secondary aim was to identify melanoma-specific RCM features.

METHODS

The study enrolled patients ≥18 years that underwent biopsy of skin lesions clinically suspected to be melanoma. One hundred lesions imaged by RCM were randomly selected from 439 lesions prospectively collected at four pigmented lesion clinics. The study data set included 23 melanomas, three basal cell and two squamous cell carcinomas, 11 indeterminate melanocytic lesions and 61 benign lesions including 50 nevi. Three expert RCM evaluators were blinded to clinical or dermoscopic images, and to the final histopathological diagnosis. Evaluators independently issued a binary RCM-based management decision, 'biopsy' vs. 'observation'; these decisions were scored against histopathological diagnosis, with 'biopsy' as the correct management decision for malignant and indeterminate lesions. A subset analysis of 23 melanomas and 50 nevi with unequivocal histopathological diagnosis was performed to identify melanoma-specific RCM features.

RESULTS

Sensitivity, specificity and diagnostic accuracy were 74%, 67% and 70% for reader 1, 46%, 84% and 69% for reader 2, and 72%, 46% and 56% for reader 3, respectively. The overall kappa for management decisions was 0.34. Readers had unanimous agreement on management for 50 of the 100 lesions. Non-specific architecture, non-visible papillae, streaming of nuclei, coarse collagen fibres and abnormal vasculature showed a significant association with melanoma in the evaluation of at least two readers.

CONCLUSIONS

Reflectance confocal microscopy tele-consultation of especially challenging lesions, based on image review without benefit of clinical or dermoscopy images, may be associated with limited diagnostic accuracy and interobserver agreement. Architectural and stromal criteria may emerge as potentially useful and reproducible criteria for melanoma diagnosis.

Genetically predicted complement component 4A expression: effects on memory function and middle temporal lobe activation

BACKGROUND

The longstanding association between the major histocompatibility complex (MHC) locus and schizophrenia (SZ) risk has recently been accounted for, partially, by structural variation at the complement component 4 (C4) gene. This structural variation generates varying levels of C4 RNA expression, and genetic information from the MHC region can now be used to predict C4 RNA expression in the brain. Increased predicted C4A RNA expression is associated with the risk of SZ, and C4 is reported to influence synaptic pruning in animal models.

METHODS

Based on our previous studies associating MHC SZ risk variants with poorer memory performance, we tested whether increased predicted C4A RNA expression was associated with reduced memory function in a large (n = 1238) dataset of psychosis cases and healthy participants, and with altered task-dependent cortical activation in a subset of these samples.

RESULTS

We observed that increased predicted C4A RNA expression predicted poorer performance on measures of memory recall (p = 0.016, corrected). Furthermore, in healthy participants, we found that increased predicted C4A RNA expression was associated with a pattern of reduced cortical activity in middle temporal cortex during a measure of visual processing (p < 0.05, corrected).

CONCLUSIONS

These data suggest that the effects of C4 on cognition were observable at both a cortical and behavioural level, and may represent one mechanism by which illness risk is mediated. As such, deficits in learning and memory may represent a therapeutic target for new molecular developments aimed at altering C4's developmental role.

Oxidative Stress and Cardiovascular Risk in Type 1 Diabetes Mellitus: Insights From the DCCT/EDIC Study

Background

Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus.

Methods and Results

A random subcohort of 349 participants was selected from the DCCT / EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT , and 1 to 2 years post‐ DCCT ( EDIC years 1 and 2) were measured for markers of oxidative stress, including plasma myeloperoxidase, paraoxonase activity, urinary F 2α isoprostanes, and its metabolite, 2,3 dinor‐8 iso prostaglandin F 2α . Following adjustment for glycated hemoblobin and weighting the observations inversely proportional to the sampling selection probabilities, higher paraoxonase activity, reflective of antioxidant activity, and 2,3 dinor‐8 iso prostaglandin F 2α , an oxidative marker, were significantly associated with lower risk of cardiovascular disease (−4.5% risk for 10% higher paraoxonase, P <0.003; −5.3% risk for 10% higher 2,3 dinor‐8 iso prostaglandin F 2α , P =0.0092). In contrast, the oxidative markers myeloperoxidase and F 2α isoprostanes were not significantly associated with cardiovascular disease after adjustment for glycated hemoblobin. There were no significant differences between DCCT intensive and conventional treatment groups in the change in all biomarkers across time segments.

Conclusions

Heightened antioxidant activity (rather than diminished oxidative stress markers) is associated with lower cardiovascular disease risk in type 1 diabetes mellitus, but these biomarkers did not change over time with intensification of glycemic control.

Clinical Trial Registration

URL : https://www.clinicaltrials.gov . Unique identifiers: NCT 00360815 and NCT 00360893.

Widespread white matter microstructural differences in schizophrenia across 4322 individuals: results from the ENIGMA Schizophrenia DTI Working Group

The regional distribution of white matter (WM) abnormalities in schizophrenia remains poorly understood, and reported disease effects on the brain vary widely between studies. In an effort to identify commonalities across studies, we perform what we believe is the first ever large-scale coordinated study of WM microstructural differences in schizophrenia. Our analysis consisted of 2359 healthy controls and 1963 schizophrenia patients from 29 independent international studies; we harmonized the processing and statistical analyses of diffusion tensor imaging (DTI) data across sites and meta-analyzed effects across studies. Significant reductions in fractional anisotropy (FA) in schizophrenia patients were widespread, and detected in 20 of 25 regions of interest within a WM skeleton representing all major WM fasciculi. Effect sizes varied by region, peaking at (d=0.42) for the entire WM skeleton, driven more by peripheral areas as opposed to the core WM where regions of interest were defined. The anterior corona radiata (d=0.40) and corpus callosum (d=0.39), specifically its body (d=0.39) and genu (d=0.37), showed greatest effects. Significant decreases, to lesser degrees, were observed in almost all regions analyzed. Larger effect sizes were observed for FA than diffusivity measures; significantly higher mean and radial diffusivity was observed for schizophrenia patients compared with controls. No significant effects of age at onset of schizophrenia or medication dosage were detected. As the largest coordinated analysis of WM differences in a psychiatric disorder to date, the present study provides a robust profile of widespread WM abnormalities in schizophrenia patients worldwide. Interactive three-dimensional visualization of the results is available at www.enigma-viewer.org.

GWAS meta-analysis reveals novel loci and genetic correlates for general cognitive function: a report from the COGENT consortium

This corrects the article DOI: 10.1038/mp.2016.244.

Rare DNA variants in the brain-derived neurotrophic factor gene increase risk for attention-deficit hyperactivity disorder: a next-generation sequencing study

Attention-deficit hyperactivity disorder (ADHD) is a prevalent and highly heritable disorder of childhood with negative lifetime outcomes. Although candidate gene and genome-wide association studies have identified promising common variant signals, these explain only a fraction of the heritability of ADHD. The observation that rare structural variants confer substantial risk to psychiatric disorders suggests that rare variants might explain a portion of the missing heritability for ADHD. Here we believe we performed the first large-scale next-generation targeted sequencing study of ADHD in 152 child and adolescent cases and 188 controls across an a priori set of 117 genes. A multi-marker gene-level analysis of rare (<1% frequency) single-nucleotide variants (SNVs) revealed that the gene encoding brain-derived neurotrophic factor (BDNF) was associated with ADHD at Bonferroni corrected levels. Sanger sequencing confirmed the existence of all novel rare BDNF variants. Our results implicate BDNF as a genetic risk factor for ADHD, potentially by virtue of its critical role in neurodevelopment and synaptic plasticity.

GWAS meta-analysis reveals novel loci and genetic correlates for general cognitive function: a report from the COGENT consortium

The complex nature of human cognition has resulted in cognitive genomics lagging behind many other fields in terms of gene discovery using genome-wide association study (GWAS) methods. In an attempt to overcome these barriers, the current study utilized GWAS meta-analysis to examine the association of common genetic variation (~8M single-nucleotide polymorphisms (SNP) with minor allele frequency ⩾1%) to general cognitive function in a sample of 35 298 healthy individuals of European ancestry across 24 cohorts in the Cognitive Genomics Consortium (COGENT). In addition, we utilized individual SNP lookups and polygenic score analyses to identify genetic overlap with other relevant neurobehavioral phenotypes. Our primary GWAS meta-analysis identified two novel SNP loci (top SNPs: rs76114856 in the CENPO gene on chromosome 2 and rs6669072 near LOC105378853 on chromosome 1) associated with cognitive performance at the genome-wide significance level (P<5 × 10^-8). Gene-based analysis identified an additional three Bonferroni-corrected significant loci at chromosomes 17q21.31, 17p13.1 and 1p13.3. Altogether, common variation across the genome resulted in a conservatively estimated SNP heritability of 21.5% (s.e.=0.01%) for general cognitive function. Integration with prior GWAS of cognitive performance and educational attainment yielded several additional significant loci. Finally, we found robust polygenic correlations between cognitive performance and educational attainment, several psychiatric disorders, birth length/weight and smoking behavior, as well as a novel genetic association to the personality trait of openness. These data provide new insight into the genetics of neurocognitive function with relevance to understanding the pathophysiology of neuropsychiatric illness.

MiR-137-derived polygenic risk: effects on cognitive performance in patients with schizophrenia and controls

Variants at microRNA-137 (MIR137), one of the most strongly associated schizophrenia risk loci identified to date, have been associated with poorer cognitive performance. As microRNA-137 is known to regulate the expression of ~1900 other genes, including several that are independently associated with schizophrenia, we tested whether this gene set was also associated with variation in cognitive performance. Our analysis was based on an empirically derived list of genes whose expression was altered by manipulation of MIR137 expression. This list was cross-referenced with genome-wide schizophrenia association data to construct individual polygenic scores. We then tested, in a sample of 808 patients and 192 controls, whether these risk scores were associated with altered performance on cognitive functions known to be affected in schizophrenia. A subgroup of healthy participants also underwent functional imaging during memory (n=108) and face processing tasks (n=83). Increased polygenic risk within the empirically derived miR-137 regulated gene score was associated with significantly lower performance on intelligence quotient, working memory and episodic memory. These effects were observed most clearly at a polygenic threshold of P=0.05, although significant results were observed at all three thresholds analyzed. This association was found independently for the gene set as a whole, excluding the schizophrenia-associated MIR137 SNP itself. Analysis of the spatial working memory fMRI task further suggested that increased risk score (thresholded at P=10^-5) was significantly associated with increased activation of the right inferior occipital gyrus. In conclusion, these data are consistent with emerging evidence that MIR137 associated risk for schizophrenia may relate to its broader downstream genetic effects.

Right iliac fossa pain from a grossly enlarged and torted appendix in a patient with known colitis

A 27-year-old man with a background of well controlled colitis presented with a 12-hour history of central abdominal pain, nausea, vomiting and fever. A diagnostic laparoscopy revealed an extremely large, gangrenous appendix, which had descended into the pelvis posterior to adhesions in the right iliac fossa and was torted 720°. The decision was taken to convert to a lower midline laparotomy and as the base appeared healthy, a standard appendicectomy was performed. The patient recovered well and was discharged after two days. The appendix measured 104mm x 53mm x 51mm. Histology revealed acute haemorrhagic and necrotising appendicitis with foci of impending perforation. There was no malignancy or mucocoele. Acute torsion (or volvulus) of the appendix is an unusual cause of this common general surgical emergency.

The other 25%: Autistic girls and women

Autism spectrum disorder (ASD) is a pervasive developmental disorder characterized by impairments in social and communicative abilities, along with the presence of ritualistic and/or repetitive behaviors. One of the under-researched areas in the ASD literature is the large gender difference in the diagnosis rates. On average, the male to female ratio stands at 4.3:1, increasing to 9:1 in the absence of comorbid intellectual impairment. It has been evidenced that compared to boys, ASD is diagnosed later in cognitively able girls, despite there being no difference in the number of visits to a health-care professional during the diagnostic process and the age at which parents first express concern. The suboptimal identification of the disorder in cognitively able girls causes a large magnitude of gender discrepancy. These statistics may not be accurate since females may camouflage their difficulties and may be undetected due to their ability to disguise their symptoms better than males. The other hypothesis of under diagnosing ASD in girls is how we quantify and diagnose it. It is based on a male-centric presentation, which does not accurately reflect the disorder in girls. Altogether, these differences may make it more challenging for medical professionals and clinicians to identify potential early signs of the disorder in girls. Hence, there is a need to develop programs to mentor girls and women on the autism spectrum in schools, colleges and industry. And there should be an insistence on inclusion of females on the autism spectrum in pharmacological research and other research projects.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

The phenotypic manifestations of rare genic CNVs in autism spectrum disorder

Significant evidence exists for the association between copy number variants (CNVs) and Autism Spectrum Disorder (ASD); however, most of this work has focused solely on the diagnosis of ASD. There is limited understanding of the impact of CNVs on the 'sub-phenotypes' of ASD. The objective of this paper is to evaluate associations between CNVs in differentially brain expressed (DBE) genes or genes previously implicated in ASD/intellectual disability (ASD/ID) and specific sub-phenotypes of ASD. The sample consisted of 1590 cases of European ancestry from the Autism Genome Project (AGP) with a diagnosis of an ASD and at least one rare CNV impacting any gene and a core set of phenotypic measures, including symptom severity, language impairments, seizures, gait disturbances, intelligence quotient (IQ) and adaptive function, as well as paternal and maternal age. Classification analyses using a non-parametric recursive partitioning method (random forests) were employed to define sets of phenotypic characteristics that best classify the CNV-defined groups. There was substantial variation in the classification accuracy of the two sets of genes. The best variables for classification were verbal IQ for the ASD/ID genes, paternal age at birth for the DBE genes and adaptive function for de novo CNVs. CNVs in the ASD/ID list were primarily associated with communication and language domains, whereas CNVs in DBE genes were related to broader manifestations of adaptive function. To our knowledge, this is the first study to examine the associations between sub-phenotypes and CNVs genome-wide in ASD. This work highlights the importance of examining the diverse sub-phenotypic manifestations of CNVs in ASD, including the specific features, comorbid conditions and clinical correlates of ASD that comprise underlying characteristics of the disorder.

Familiality and SNP heritability of age at onset and episodicity in major depressive disorder

BACKGROUND

Strategies to dissect phenotypic and genetic heterogeneity of major depressive disorder (MDD) have mainly relied on subphenotypes, such as age at onset (AAO) and recurrence/episodicity. Yet, evidence on whether these subphenotypes are familial or heritable is scarce. The aims of this study are to investigate the familiality of AAO and episode frequency in MDD and to assess the proportion of their variance explained by common single nucleotide polymorphisms (SNP heritability).

METHOD

For investigating familiality, we used 691 families with 2-5 full siblings with recurrent MDD from the DeNt study. We fitted (square root) AAO and episode count in a linear and a negative binomial mixed model, respectively, with family as random effect and adjusting for sex, age and center. The strength of familiality was assessed with intraclass correlation coefficients (ICC). For estimating SNP heritabilities, we used 3468 unrelated MDD cases from the RADIANT and GSK Munich studies. After similarly adjusting for covariates, derived residuals were used with the GREML method in GCTA (genome-wide complex trait analysis) software.

RESULTS

Significant familial clustering was found for both AAO (ICC = 0.28) and episodicity (ICC = 0.07). We calculated from respective ICC estimates the maximal additive heritability of AAO (0.56) and episodicity (0.15). SNP heritability of AAO was 0.17 (p = 0.04); analysis was underpowered for calculating SNP heritability of episodicity.

CONCLUSIONS

AAO and episodicity aggregate in families to a moderate and small degree, respectively. AAO is under stronger additive genetic control than episodicity. Larger samples are needed to calculate the SNP heritability of episodicity. The described statistical framework could be useful in future analyses.

Clinical and microbiological evaluation of epidural and regional anaesthesia catheters in injured UK military personnel

INTRODUCTION

The adoption of regional and epidural analgesia in UK military personnel injured in action during Op HERRICK increased from 2008, in line with structural and environmental developments in the UK medical treatment facility. Historically, there have been concerns that invasive analgesic techniques could carry an increased risk of infection, due to the mechanism of injury and the environmental conditions in which the injuries were sustained. Consequently, the epidural and continuous peripheral nerve blockade (CPNB) catheters that were inserted in UK military personnel during a 33-month period of Op HERRICK were clinically and microbiologically examined, after subsequent admission to the University Hospitals Birmingham (UHB) NHS Trust.

METHODS

Data on epidural and CPNB insertions were collected via the specialist pain service at UHB over the study period, including de novo and replacement insertions performed in both Afghanistan and the UK. Patients were regularly reviewed and relevant clinical concerns were documented in patients' case notes as necessary. The anatomical site, duration of placement and the results of microbiological culture of the epidural and CPNB catheter tips were all recorded.

RESULTS

Overall, 236 catheters were assessed, of which 151 catheter tips (64%) were cultured (85 epidural, 66 CPNB). Of these, 48 grew bacteria (34% of cultured epidurals and 29% of cultured CPNB). There was no difference between the colonisation rates of epidurals inserted in Afghanistan and the UK. Only one infection related to a misplaced epidural catheter was confirmed.

CONCLUSIONS

With the exception of the epidural (34%) and proximal sciatic (42%) catheters, these figures, in a military cohort characterised by significant injury scores, are consistent with those reported for civilian surgical patients. The results strongly support the expansion of regional analgesia during Op HERRICK from 2008 onwards. The outcomes suggest a possible translation into civilian major trauma practice.

The one and the many: effects of the cell adhesion molecule pathway on neuropsychological function in psychosis

BACKGROUND

Genetic studies of single gene variants have been criticized as providing a simplistic characterization of the genetic basis of illness risk that ignores the effects of other variants within the same biological pathways. Of candidate biological pathways for schizophrenia (SZ), the cell adhesion molecule (CAM) pathway has repeatedly been linked to both psychosis and neurocognitive dysfunction. Here we tested, using risk allele scores derived from the Schizophrenia Psychiatric Genome-Wide Association Study Consortium (PGC-SCZ), whether alleles within the CAM pathway were correlated with poorer neuropsychological function in patients.

METHOD

In total, 424 patients with psychosis were assessed in areas of cognitive ability typically found to be impaired in SZ: intelligence quotient, memory, working memory and attentional control. CAM pathway genes were identified using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Alleles within these genes identified as significantly associated with SZ risk in the PGC-SCZ were then used to calculate a CAM pathway-based polygenic risk allele score for each patient and these scores were tested for association with cognitive ability.

RESULTS

Increased CAM pathway polygenic risk scores were significantly associated with poorer performance on measures of memory and attention, explaining 1-3% of variation on these measures. Notably, the most strongly associated single nucleotide polymorphism (SNP) in the CAM pathway (rs9272105 within HLA-DQA1) explained a similar amount of variance in attentional control, but not memory, as the polygenic risk analysis.

CONCLUSIONS

These data support a role for the CAM pathway in cognitive function, both at the level of individual SNPs and the wider pathway. In so doing these data highlight the value of pathway-based polygenic risk score studies as well as single gene studies for understanding SZ-associated deficits in cognition.

Constituents of Agaricus xanthodermus Genevier: The First Naturally Endogenous Azo Compound and Toxic Phenolic Metabolites

Extraction of fresh sporophores of the fungus Agaricus xanthodermus yields 4,4′-dihydroxy-azobenzene, phenol, p-quinol, and 4,4′-dihydroxybiphenyl. This is the first report of an azo compound arising endogenously in nature, while phenol, p-quinol and 4,4′-dihydroxybiphenyl have not previously been isolated from higher fungi. Phenol is present in fruitbodies in sufficiently high concentration to account for the toxicity of A. xanthodermus.

Allelic differences between Europeans and Chinese for CREB1 SNPs and their implications in gene expression regulation, hippocampal structure and function, and bipolar disorder susceptibility

Bipolar disorder (BD) is a polygenic disorder that shares substantial genetic risk factors with major depressive disorder (MDD). Genetic analyses have reported numerous BD susceptibility genes, while some variants, such as single-nucleotide polymorphisms (SNPs) in CACNA1C have been successfully replicated, many others have not and subsequently their effects on the intermediate phenotypes cannot be verified. Here, we studied the MDD-related gene CREB1 in a set of independent BD sample groups of European ancestry (a total of 64,888 subjects) and identified multiple SNPs significantly associated with BD (the most significant being SNP rs6785[A], P=6.32 × 10(-5), odds ratio (OR)=1.090). Risk SNPs were then subjected to further analyses in healthy Europeans for intermediate phenotypes of BD, including hippocampal volume, hippocampal function and cognitive performance. Our results showed that the risk SNPs were significantly associated with hippocampal volume and hippocampal function, with the risk alleles showing a decreased hippocampal volume and diminished activation of the left hippocampus, adding further evidence for their involvement in BD susceptibility. We also found the risk SNPs were strongly associated with CREB1 expression in lymphoblastoid cells (P<0.005) and the prefrontal cortex (P<1.0 × 10(-6)). Remarkably, population genetic analysis indicated that CREB1 displayed striking differences in allele frequencies between continental populations, and the risk alleles were completely absent in East Asian populations. We demonstrated that the regional prevalence of the CREB1 risk alleles in Europeans is likely caused by genetic hitchhiking due to natural selection acting on a nearby gene. Our results suggest that differential population histories due to natural selection on regional populations may lead to genetic heterogeneity of susceptibility to complex diseases, such as BD, and explain inconsistencies in detecting the genetic markers of these diseases among different ethnic populations.