Increase transparency and reproducibility of real-world evidence in rare diseases through disease-specific Federated Data Networks

PURPOSE

In rare diseases, real-world evidence (RWE) generation is often restricted due to small patient numbers and global geographic distribution. A federated data network (FDN) approach brings together multiple data sources harmonized for collaboration to increase the power of observational research. In this paper, we review how to increase reproducibility and transparency of RWE studies in rare diseases through disease-specific FDNs.

METHOD

To be successful, a multiple stakeholder scientific FDN collaboration requires a strong governance model in place. In such a model, each database owner remains in full control regarding the use of and access to patient-level data and is responsible for data privacy, ethical, and legal compliance. Provided that all this is well documented and good database descriptions are in place, such a governance model results in increased transparency, while reproducibility is achieved through data curation and harmonization, and distributed analytical methods.

RESULTS

Leveraging the OHDSI community set of methods and tools, two rare disease-specific FDNs are discussed in more detail. For multiple myeloma, HONEUR-the Haematology Outcomes Network in Europe-has built a strong community among the data partners dedicated to scientific exchange and research. To advance scientific knowledge in pulmonary hypertension (PH) an FDN, called PHederation, was established to form a partnership of research institutions with PH databases coming from diverse origins.

Guidance for the gastrointestinal evaluation and management of iron deficiency in Sub-Saharan Africa

BACKGROUND

Over 30% of the world's population is anaemic, with a significant proportion of these being iron deficient. As iron deficiency (ID) anaemia in men and post-menopausal women is mostly caused by gastrointestinal blood loss or malabsorption, the initial evaluation of a patient with ID anaemia involves referral to a gastroenterologist. The current drive towards patient blood management in sub-Saharan Africa (SSA)prescribes that we regulate not only the use of blood transfusion but also the management of patients in whom the cause of iron loss or inadequate iron absorption is sought. Recommendations have been developed to: (i) aid clinicians in the evaluation of suspected gastrointestinal iron loss and iron malabsorption, and often a combination of these; (ii) improve clinical outcomes for patients with gastrointestinal causes of ID; (iii) provide current, evidence-based, context-specific recommendations for use in the management of ID; and (iv) conserve resources by ensuring rational utilisation of blood and blood products.

METHOD

Development of the guidance document was facilitated by the Gastroenterology Foundation of Sub-Saharan Africa and the South African Gastroenterology Society. The consensus recommendations are based on a rigorous process involving 21 experts in gastroenterology and haematology in SSA. Following discussion of the scope and purpose of the guidance document among the experts, an initial review of the literature and existing guidelines was undertaken. Thereafter, draft recommendation statements were produced to fulfil the outlined purpose of the guidance document. These were reviewed in a round-table discussion and were subjected to two rounds of anonymised consensus voting by the full committee in an electronic Delphi exercise during 2022 using the online platform, Research Electronic Data Capture. Recommendations were modified by considering feedback from the previous round, and those reaching a consensus of over 80% were incorporated into the final document. Finally, 44 statements in the document were read and approved by all members of the working group.

CONCLUSION

The recommendations incorporate six areas, namely: general recommendations and practice, Helicobacter pylori, coeliac disease, suspected small bowel bleeding, inflammatory bowel disease, and preoperative care. Implementation of the recommendations is aimed at various levels from individual practitioners to healthcare institutions, departments and regional, district, provincial and national platforms. It is intended that the recommendations spur the development of centre-specific guidelines and that they are integrated with the relevant patient blood management protocols. Integration of the recommendations is intended to promote optimal evaluation and management of patients with ID, regardless of the presence of anaemia.

Patient Preferences in Pulmonary Arterial Hypertension, a Latent Class Analysis to Identify Preference Heterogeneity

OBJECTIVES

Pulmonary arterial hypertension (PAH) is a chronic, progressive disease of the pulmonary circulation characterized by vascular remodeling that, if untreated, can lead to right heart dysfunction and death. This analysis measured heterogeneity in patient preferences for PAH-specific treatment regimens.

METHOD

Adult patients with PAH with slight to marked limitations during physical activity were recruited through a patient organization in Germany. Participants completed an online best-worst scaling case 3 survey. Patients chose among 3 hypothetical treatment profiles defined by 6 benefits and risks at varying levels. Participants completed 12 choice tasks. Preference heterogeneity was assessed using latent class analysis.

RESULTS

A total of 83 participants (76% female) completed the survey. Best-fit model revealed 4 classes. Class 1 (19% of participants) assigned importance to multiple attributes particularly side effects, class 2 (34%) to physical activity limitations, class 3 (30%) to survival and physical activity limitations, and class 4 (17%) to survival. No differences in sociodemographic characteristics were observed across classes. Compared with other classes, class 4 was most likely to report having marked physical activity limitations (79%) and needing daily help (100%), while considering higher daily activity levels to be ordinary (walking >1 km [71%] or climbing several flights of stairs [50%]).

CONCLUSION

This first patient preference study in a PAH population suggests that physical activity limitations in addition to survival matter most to patients; however, preference heterogeneity between groups of patients was observed. Patient preferences should be considered in treatment decision making to better balance patient's expectations regarding the known risk-benefit ratio of treatment.

Clinical evaluation of code-based algorithms to identify patients with pulmonary arterial hypertension in healthcare databases

Pulmonary arterial hypertension (PAH) is a rare subgroup of pulmonary hypertension (PH). Claims and administrative databases can be particularly important for research in rare diseases; however, there is a lack of validated algorithms to identify PAH patients using administrative codes. We aimed to measure the accuracy of code-based PAH algorithms against the true clinical diagnosis by right heart catheterization (RHC). This study evaluated algorithms in patients who were recorded in two linkable data assets: the Stanford Healthcare administrative electronic health record database and the Stanford Vera Moulton Wall Center clinical PH database (which records each patient's RHC diagnosis). We assessed the sensitivity and specificity achieved by 16 algorithms (six published). In total, 720 PH patients with linked data available were included and 558 (78%) of these were PAH patients. Algorithms consisting solely of a P(A)H-specific diagnostic code classed all or almost all PH patients as PAH (sensitivity >97%, specificity <12%) while multicomponent algorithms with well-defined temporal sequences of procedure, diagnosis and treatment codes achieved a better balance of sensitivity and specificity. Specificity increased and sensitivity decreased with increasing algorithm complexity. The best-performing algorithms, in terms of fewest misclassified patients, included multiple components (e.g., PH diagnosis, PAH treatment, continuous enrollment for ≥6 months before and ≥12 months following index date) and achieved sensitivities and specificities of around 95% and 38%, respectively. Our findings help researchers tailor their choice and design of code-based PAH algorithms to their research question and demonstrate the importance of including well-defined temporal components in the algorithms.

From game engagement to craving responses - The role of gratification and compensation experiences during video-gaming in casual and at-risk gamers

Introduction

Although playing videogames is a common leisure activity some individuals develop problematic gaming behaviors or even symptoms of a gaming disorder. Game engagement may be involved in reinforcement learning that may result in experiences of craving, an important feature of gaming disorder. In the following study we aimed to approach the question which aspects contribute to increased craving for gaming.

Methods

Overall, 439 individuals participated in an online survey, answering questionnaires on game engagement, experience of gratification and compensation, craving, and symptoms of gaming disorder. A mediation model testing if the association between game engagement and facets of craving are mediated by the experience of gratification and compensation during gaming.

Results

Three facets of craving (reward/relief, physiological, obsessive craving) were statistically explained by game engagement and the experience of gratification and compensation. Models differed between casual gamers and at-risk gamers. The effects on reward/relief and physiological craving were fully mediated in the casual group and partially mediated in the at-risk group by gratification and compensation experiences.

Conclusion

Game engagement may contribute to the development of craving by increasing the experience of gratification and compensation and thus might be important in reinforcement learning. Games evoking a high engagement may therefore have a higher addictive potential. Further processes potentially related to game engagement, such as intrusive thoughts and desire thinking, which are related to craving experiences, should be considered in future studies.

[Diagnosis and Treatment in frontobasal fractures]

Traumatic brain injury can result in frontobasal fractures (FBF). The goals of treatment for FBF are to eliminate primary morbidity and/or prevent secondary morbidity. Of particular importance in this regard is the proximity of important sensory organs for hearing, vision, smell, and taste, as well as their supplying nervous structures. Medical history, clinical findings, or CT scan are necessary and should lead to an individual evaluation. Depending on the severity of the fractures, the following disciplines may be involved in the treatment of FBF: neurosurgery, plastic surgery, oral and maxillofacial surgery, and/or otorhinolaryngology. Particularly less invasive endoscopic endonasal therapy is a specialty of otorhinolaryngologic surgeons and has not been widely established in other disciplines. The present work provides an overview of the current state of the art in terms of the following aspects, taking into account the current literature: anatomic principles, classification of fractures, diagnostics (in particular clinical examination, imaging, and laboratory chemistry tests), clinical symptoms, and treatment.

Safety of macitentan for the treatment of pulmonary hypertension: Real‐world experience from the OPsumit® USers Registry (OPUS) and OPsumit® Historical USers cohort (OrPHeUS)

Macitentan is an oral endothelin receptor antagonist for the management of pulmonary arterial hypertension (PAH). The OPsumit® USers Registry (OPUS) and the OPsumit® Historical USers cohort (OrPHeUS) medical chart review provide real‐world data for patients newly initiating macitentan. This study aims to describe the characteristics, safety profile, and clinical outcomes of PAH patients newly treated with macitentan in the combined OPUS/OrPHeUS data set. OPUS was a prospective, multicenter, long‐term, observational drug registry from April 2014 to June 2020. OrPHeUS was a retrospective, US, multicenter chart review: observation period October 2013 to March 2017. All analyses were descriptive. At registry closure in June 2020, the combined population consisted of 5654 patients, of whom 81.9% were diagnosed with PAH. For these 4626 patients, median duration of macitentan exposure observed was 14.5 (Q1 = 5.2, Q3 = 29.0) months; idiopathic PAH (54.8%) was the most common form of PAH; macitentan was initiated as monotherapy (37.9%), or as part of double (48.0%) or triple therapy (14.1%); discontinuation due to nonhepatic/hepatic adverse events occurred in 17.1%/0.3% of patients; 9.9% of patients experienced ≥1 hepatic adverse events; Kaplan–Meier estimates showed that at 1 year 59.9% (95% confidence interval: 58.3, 61.5) of patients were free from hospitalization and survival was 90.4% (89.3, 91.3). This analysis of real‐world data from the combined OPUS and OrPHeUS populations demonstrated that macitentan is well tolerated in a large, diverse population of PAH patients, with overall and hepatic safety profiles consistent with previous macitentan clinical trials.

Standardizing registry data to the OMOP Common Data Model: experience from three pulmonary hypertension databases

Background

The Observational Medical Outcomes Partnership (OMOP) Common Data Model (CDM) can be used to transform observational health data to a common format. CDM transformation allows for analysis across disparate databases for the generation of new, real-word evidence, which is especially important in rare disease where data are limited. Pulmonary hypertension (PH) is a progressive, life-threatening disease, with rare subgroups such as pulmonary arterial hypertension (PAH), for which generating real-world evidence is challenging. Our objective is to document the process and outcomes of transforming registry data in PH to the OMOP CDM, and highlight challenges and our potential solutions.

Methods

Three observational studies were transformed from the Clinical Data Interchange Standards Consortium study data tabulation model (SDTM) to OMOP CDM format. OPUS was a prospective, multi-centre registry (2014–2020) and OrPHeUS was a retrospective, multi-centre chart review (2013–2017); both enrolled patients newly treated with macitentan in the US. EXPOSURE is a prospective, multi-centre cohort study (2017–ongoing) of patients newly treated with selexipag or any PAH-specific therapy in Europe and Canada. OMOP CDM version 5.3.1 with recent OMOP CDM vocabulary was used. Imputation rules were defined and applied for missing dates to avoid exclusion of data. Custom target concepts were introduced when existing concepts did not provide sufficient granularity.

Results

Of the 6622 patients in the three registry studies, records were mapped for 6457. Custom target concepts were introduced for PAH subgroups (by combining SNOMED concepts or creating custom concepts) and World Health Organization functional class. Per the OMOP CDM convention, records about the absence of an event, or the lack of information, were not mapped. Excluding these non-event records, 4% (OPUS), 2% (OrPHeUS) and 1% (EXPOSURE) of records were not mapped.

Conclusions

SDTM data from three registries were transformed to the OMOP CDM with limited exclusion of data and deviation from the SDTM database content. Future researchers can apply our strategy and methods in different disease areas, with tailoring as necessary. Mapping registry data to the OMOP CDM facilitates more efficient collaborations between researchers and establishment of federated data networks, which is an unmet need in rare diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01434-3.

Influence of travel burden on tumor classification and survival of head and neck cancer patients

PURPOSE

Cancer patients have to overcome various barriers to obtain diagnostics and treatment at head and neck cancer centers. Travel distance to a specialized hospital may result in psychosocial and financial distress, thus interfering with diagnostics, treatment, and follow-up care. In this study, we have aimed to analyze the association of travel distance with cTNM status, UICC stage at primary diagnosis, and survival outcomes of head and neck cancer (HNC) patients.

METHODS

We have analyzed data of 1921 consecutive HNC patients diagnosed between 2014 and 2019 at the head and neck cancer center of the Comprehensive Cancer Center Ulm (CCCU), Germany. Postal code-based travel distance calculation in kilometers, TNM status, and UICC stage were recorded at initial diagnosis. The assembly of travel distance-related groups (short, intermediate, long-distance) has been investigated. Moreover, group-related survival and recurrence analysis have been performed.

RESULTS

In contrast to observations from overseas, no association of travel distance and higher cTNM status or UICC stage at primary diagnosis has been observed. Furthermore, no significant differences for recurrence-free survival and overall survival by travel distance were detected.

CONCLUSION

In southern Germany, travel distance to head and neck cancer centers seems to be tolerable. Travel burden is not synonymous with travel distance alone but also involves sociodemographic, monetary, and disease-specific aspects as well as accessibility to proper infrastructure of transport and health care system.

Colorectal cancer liver metastases: management and five-year survival in a South African patient cohort

BACKGROUND

Approximately 25% of patients with colorectal cancer (CRC) will be diagnosed with CRC liver metastases (CRCLM) during the course of their disease. No data regarding CRCLM presentation, management and survival outcomes has been published from either the private or public health care sectors in South Africa. This study aimed to address this deficit, reporting on a private sector cohort.

METHODS

A retrospective review of a private health care funder's database from 1 January 2008 to 31 December 2015 was performed. ICD-10 diagnosis codes were used to identify CRC and CRCLM. Procedure codes assigned to hospital admissions were used to identify the type of surgical treatment. Chemotherapy was identified by the WHO Anatomical Therapeutic Chemical classification system of medicines. Treatment patterns were assessed and five-year overall survival (OS) was calculated. Survival was estimated using the Kaplan-Meier method, and Cox proportional-hazards regression was used for between group survival comparisons.

RESULTS

Six hundred and one (601) of 3 412 patients presenting with CRC (17.6%) were diagnosed with CRCLM at presentation or during the follow-up period. Sixty patients with CRCLM (10.0%) underwent resection of the primary CRC and liver resection for metastases, 281 (46.8%) underwent CRC resection only, 180 (30%) received chemotherapy only, and 47 (7.8%) received no treatment. Five-year OS for these groups were 57.3%, 15.6%, 9.8% and 0% respectively.

CONCLUSION

Five-year OS of the various CRCLM treatment pathways in a South African private sector population compares to results published in international series. However, a smaller proportion of patients with CRCLM underwent liver resection, compared to international studies.

Polyacrylamide Bead Sensors for in vivo Quantification of Cell-Scale Stress in Zebrafish Development

Mechanical stress exerted and experienced by cells during tissue morphogenesis and organ formation plays an important role in embryonic development. While techniques to quantify mechanical stresses in vitro are available, few methods exist for studying stresses in living organisms. Here, we describe and characterize cell-like polyacrylamide (PAAm) bead sensors with well-defined elastic properties and size for in vivo quantification of cell-scale stresses. The beads were injected into developing zebrafish embryos and their deformations were computationally analyzed to delineate spatio-temporal local acting stresses. With this computational analysis-based cell-scale stress sensing (COMPAX) we are able to detect pulsatile pressure propagation in the developing neural rod potentially originating from polarized midline cell divisions and continuous tissue flow. COMPAX is expected to provide novel spatio-temporal insight into developmental processes at the local tissue level and to facilitate quantitative investigation and a better understanding of morphogenetic processes.

P4607A specific complex I-induced ROS modulator, OP2113, is a new cardioproctective agent against acute myocardial infarction injuries during reperfusion

Introduction

Hospital death rates due to myocardial infarction are still a concern and heart failure occurs in nearly a quarter of older patients who present with ST elevation myocardial infarction. Novel therapies are thus desperately needed to reduce infarct size to preserve left ventricular function and to prevent the onset of heart failure.

Purpose

OP2113, trithio-p-methoxyphenylpropene (anethole trithione, 5-(4-methoxyphenyl)-3H-1,2-dithiole-3-thione, anethole dithionethiol), a potential suppressor of complex I superoxide/hydrogen peroxide (ROS) production was evaluated in a sheep model of regional ischemia in order to demonstrate cardioprotective properties against infarct size and left ventricular function remodeling.

Methods

A series of experiments was performed in vitro on isolated mitochondria and on C2C12 cells to clarify the mechanism of action and to test whether OP2113 impacts biological variables of mitochondria. In vivo, anesthetized sheep underwent 60 min ischemia and 120 min reperfusion and either received OP2113 (1–5 μg/kg, i.v at start of and for the duration of the reperfusion) or the vehicle. The animals underwent then a 3-day follow-up period until euthanasia. Ischemic biomarkers, troponin I, CPK, and ventricular function through echocardiography were quantified during reperfusion and infarct size through histological analysis.

Results

OP2113 reduced ROS production from site IQ in mitochondria isolated from rat skeletal muscle, with IC50 of 26±1.4 μM (n=3). It is specific; IC50 values for other sites are at least 15-fold higher (site IIIQo – 414 μM; site IIF – 582 μM; sites IF/DH, PF, GQ >5 mM). Furthermore, OP2113 did not affect oxidative phosphorylation, respiration or growth of C2C12 cells. In the sheep model, OP2113 (1–10 μg/kg) dose-dependently prevented reperfusion-induced ST segment increase during the first minutes. When OP2113 plasmatic concentration was superior to 1 ng/mL (generally associated with a threshold dose of 5 μg/kg), troponin Ic levels measured over the experiment was strongly decreased and the cardiac function significantly improved (+86%), when compared to the vehicle group (left panel). Finally, the infarct size was diminished by 57% comparing to the vehicle group (10.3% vs 23.8%, respectively, right panel).

Conclusion

In a large animal model of ischemia-reperfusion, OP2113 with very low infused dose, reduced ST segment elevation, reduced troponin release, improved left ejection fraction and reduced infarct size. Collectively, these results demonstrate that OP2113, through a new mechanism of action, is a potent cardioprotective compound.

P3674Patient characteristics and treatment patterns in the multicentre, retrospective chart review of first-time Opsumit (macitentan) users in the United States (OrPHeUS)

Introduction

The OPsumit® Historical USers cohort (OrPHeUS) is a multicentre, US, retrospective medical chart review conducted to supplement the OPsumit® USers (OPUS) Registry to fulfil the FDA request to characterise the safety of macitentan in clinical practice.

Purpose

To describe patient characteristics, treatment patterns, hepatic safety and survival in patients with pulmonary hypertension (PH) newly treated with macitentan.

Methods

OrPHeUS (NCT03197688) aimed to include 2200 new users of macitentan, between October 2013 and March 2017, who were not enrolled in OPUS. Here we present patients with follow-up data, including characteristics and treatment patterns at macitentan initiation, hepatic adverse events (HAEs) identified using preferred terms in chart entries and pharmacovigilance reporting, hospitalisations and survival.

Results

OrPHeUS included 2982 patients newly treated with macitentan and with follow-up data; the reason for macitentan prescription was pulmonary arterial hypertension (PAH) in 2362 (79.3%) patients, other PH aetiologies in 612 (20.6%) patients and 8 patients with other/unknown reasons. At macitentan initiation, the median (Q1, Q3) age of the patients was 62 (51, 72) years and 73.9% were female. WHO functional class (FC) was documented in 654 (21.9%) patients, 35.6% of patients were in FC I/II and 64.4% in FC III/IV; median (Q1, Q3) 6-minute walk distance, documented in 411 (13.8%) patients, was 293 (200, 383) metres. At macitentan initiation, 41.5% (n=1239) of patients were not receiving PAH therapy, 46.3% (n=1382) were already receiving one PAH therapy and 11.9% (n=356) were already receiving two PAH therapies. The median (Q1, Q3) exposure to macitentan was 14.9 (5.6, 27.1) months; 57% and 43% of patients had exposures of >12 and >18 months. During the exposure period, 933 (31.3%) patients discontinued treatment, including 474 (15.9%) patients who discontinued due to an adverse event (AE), 6 (0.2%) due to a HAE, 449 (15.1%) for reasons other than an AE/HAE, and 4 (0.1%) for unknown reasons. There were 275 (9.2%) patients who experienced ≥1 HAE (incidence rate [IR]: 0.07 [95% CI, 0.06, 0.08] per 1 person-year); alanine aminotransferase (ALT) or aspartate aminotransferase (AST) ≥3x upper limit of normal (ULN) were experienced by 113 (3.8%) patients (IR: 0.028 [95% CI, 0.023, 0.033] per 1 person-year); ALT/AST ≥x3 ULN and bilirubin ≥2x ULN was experienced by 33 (1.1%) patients (IR: 0.008 [95% CI, 0.006, 0.011] per 1 person-year). There were 1148 (38.5%) patients who experienced at least one hospitalisation (IR: 0.36 [95% CI, 0.34, 0.39] per 1 person-year). The 12-month Kaplan-Meier survival estimate was 92% (95% CI, 91, 93).

Conclusion

OrPHeUS provides additional real-world evidence in patients newly treated with macitentan, confirming the hepatic safety profile of macitentan.

Acknowledgement/Funding

Actelion Pharmaceuticals Ltd

Using deterministic record linkage to link ambulance and emergency department data: is it possible without patient identifiers? A case study from the UK

INTRODUCTION

Routine linkage of emergency ambulance records with those from the emergency department is uncommon in the UK. Our study, known as the Pre-Hospital Emergency Department Data Linking Project (PHED Data), aimed to link records of all patients conveyed by a single emergency ambulance service to thirteen emergency departments in the UK from 2012-2016.

OBJECTIVES

We aimed to examine the feasibility and resource requirements of collecting de-identified emergency department patient record data and, using a deterministic matching algorithm, linking it to ambulance service data.

METHODS

We used a learning log to record contacts and activities undertaken by the research team to achieve data linkage. We also conducted semi-structured interviews with information management/governance staff involved in the process.

RESULTS

We found that five steps were required for successful data linkage for each hospital trust. The total time taken to achieve linkage was a mean of 65 weeks. A total of 958,057 emergency department records were obtained and, of these, 81% were linked to a corresponding ambulance record. The match rate varied between hospital trusts (50%-94%). Staff expressed strong enthusiasm for data linkage. Barriers to successful linkage were mainly due to inconsistencies between and within acute trusts in the recording of two ambulance event identifiers (CAD and call sign). Further data cleaning was required on emergency department fields before full analysis could be conducted. Ensuring the data was not re-identifiable limited validation of the matching method.

CONCLUSION

We conclude that deterministic record linkage based on the combination of two event identifiers (CAD and call sign) is possible. There is an appetite for data linkage in healthcare organisations but it is a slow process. Developments in standardising the recording of emergency department data are likely to improve the quality of the resultant linked dataset. This would further increase its value for providing evidence to support improvements in health care delivery.

HIGHLIGHTS

Ambulance records are rarely linked to other datasets; this study looks at the feasibility and resource requirement to use deterministic matching to link ambulance and emergency department data for patients conveyed by ambulance to the emergency department.It is possible to link these data, with an average match rate of 81% across 13 emergency departments and one large ambulance trust.All trusts approached provided match-able data and there was an appetite for data linkage; however, it was a long process taking an average of 65 weeks.We conclude that deterministic matching using no patient identifiers can be used in this setting.

Carotid CTA at the Lowest Tube Voltage (70 kV) in Comparison with Automated Tube Voltage Adaption

BACKGROUND AND PURPOSE

CTA is the imaging modality of choice in many institutions for the evaluation of the supraaortic vessels, but radiation exposure remains a matter of concern. Our aim was to evaluate a 70-kV protocol for CT angiography of the carotid arteries with respect to image quality and radiation exposure compared with automated tube voltage adaption.

MATERIALS AND METHODS

A total of 90 consecutive patients were included in this prospective study and randomized to the study group (n = 45, 70 kV) or control group (n = 45, automated tube voltage adaptation). Volume CT dose indices and dose-length products were recorded in the examination protocol. Image quality was assessed as arterial vessel contrast, signal-to-noise ratio, contrast-to-noise ratio, and contrast-to-noise ratio in reference to the radiation dose. Subjective overall image-quality analysis, image-artifact analysis, and diagnostic evaluation were performed by 2 observers by using a 4-point Likert scale.

RESULTS

Radiation exposure was significantly lower in the study group (volume CT dose index reduced by 22%, dose-length product reduction by 20%; each P < .001). Contrast (P = .15), SNR (P = .4), and contrast-to-noise ratio (P = .5) did not show significant differences between the groups. The contrast-to-noise ratio in reference to the radiation dose was not significantly increased using the study protocol (P = .2). Subjective image quality and visualization of pathologic findings did not differ significantly between the groups.

CONCLUSIONS

Carotid CTA using the lowest available voltage (70 kV) is feasible at very-low-dose levels, while overall image quality is comparable with protocols using automated tube voltage selection.

Manifesto for a European research network into Problematic Usage of the Internet

The Internet is now all-pervasive across much of the globe. While it has positive uses (e.g. prompt access to information, rapid news dissemination), many individuals develop Problematic Use of the Internet (PUI), an umbrella term incorporating a range of repetitive impairing behaviours. The Internet can act as a conduit for, and may contribute to, functionally impairing behaviours including excessive and compulsive video gaming, compulsive sexual behaviour, buying, gambling, streaming or social networks use. There is growing public and National health authority concern about the health and societal costs of PUI across the lifespan. Gaming Disorder is being considered for inclusion as a mental disorder in diagnostic classification systems, and was listed in the ICD-11 version released for consideration by Member States (http://www.who.int/classifications/icd/revision/timeline/en/). More research is needed into disorder definitions, validation of clinical tools, prevalence, clinical parameters, brain-based biology, socio-health-economic impact, and empirically validated intervention and policy approaches. Potential cultural differences in the magnitudes and natures of types and patterns of PUI need to be better understood, to inform optimal health policy and service development. To this end, the EU under Horizon 2020 has launched a new four-year European Cooperation in Science and Technology (COST) Action Programme (CA 16207), bringing together scientists and clinicians from across the fields of impulsive, compulsive, and addictive disorders, to advance networked interdisciplinary research into PUI across Europe and beyond, ultimately seeking to inform regulatory policies and clinical practice. This paper describes nine critical and achievable research priorities identified by the Network, needed in order to advance understanding of PUI, with a view towards identifying vulnerable individuals for early intervention. The network shall enable collaborative research networks, shared multinational databases, multicentre studies and joint publications.

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

BACKGROUND

The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications.

METHODS

ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery.

RESULTS

The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784.

CONCLUSIONS

This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance.

CLINICAL TRIAL REGISTRATION

NCT03044899.

Suture material use and procurement: an audit of a public hospital surgical system in Gauteng, South Africa

BACKGROUND

Surgical systems are integral to successful, safe and cost effective clinical practice and must balance surgical demands on consumable items and their costs. Suture material is a key consumable resource, and was evaluated in an audit of consumable use and cost as well as the procurement systems within the South African Gauteng public health care sector.

AIMS

To determine suture use and cost in the four commonest general surgical procedures - abdominal wall closure, mastectomy, appendicectomy and inguinal hernia repair - in three academic Gauteng hospitals. Performance and availability were evaluated as a secondary aim in suture material use.

METHOD

A prospective observational study. Suture use was documented by the surgeon at the time of the procedure and qualitative investigation at relevant hospital departments determined suture material procurement and expenditure.

RESULTS

The surgeons in three facilities documented consistent material type and average number of units used; however, in some cases there was a lack of availability of appropriate material and breakage of generic material intraoperatively. There is no consistent and consolidated electronic record-keeping of suture stock and cost in all three hospitals, therefore cost of suture material used was not obtainable.

CONCLUSION

Clinical deficiencies in availability and quality of material may have adverse implications for patient health, healthcare costs and budgets through procedure-related complications and should be investigated. There is a lack of communication between the financial management, procurement officers, hospital and theatre stores and theatre staff. It is suggested that clinical protocols and system-based strategies be put in place to manage surgical consumables.

[Quality of life and posttraumatic stress disorder after out-of-hospital cardiac arrest]

BACKGROUND

Survival rate after out-of-hospital cardiac arrest (OHCA) is increasing. However, there is a lack of data concerning long-term quality of life of affected patients.

OBJECTIVES

This study aims to investigate the psychological effects of out-of-hospital cardiopulmonary resuscitation.

METHODS

All patients who were admitted to our hospital after OHCA between 01 January 2008 and 30 June 2015 and could be discharged in good neurological condition were asked to fill out the Impact of Event Scale-Revised (IES-R) and 36-Item Short Form Health Survey (SF-36). For statistical analysis, the mean, standard deviation and student's t‑test were used (level of significance p < 0.05).

RESULTS

Of 280 OHCA survivors, 56 patients (20.0%) were discharged from the hospital in good neurological condition. Of those, 20 patients (35.7%) were willing to participate in this study, among them 11 women and 9 men. Compared to the cohort of the German normative data, the results of the SF-36 questionnaire of OHCA survivors showed significantly lower values in all SF-36 subscales and also for the summary scores. There was no significant difference compared to patients with myocardial infarction. Average values of the IES-R subscales for intrusion and avoidance were 9.9 ± 9.3 and 9.7 ± 7.7, respectively, and 11.3 ± 7.4 for hyperarousal. Calculations indicated the suspected diagnosis of posttraumatic stress disorder in 2 of the 20 patients (10%).

DISCUSSION

Even in patients who could be discharged from the hospital after OHCA in good neurological condition, the quality of life is significantly lower compared to the standard population but not compared to patients with myocardial infarction. The data also suggest that a relevant number of patients after OHCA is affected by posttraumatic stress disorder. Further research efforts on optimization of post-resuscitation care should not only focus on survival rates but also on improving quality of life.

Proximal jejunal stoma as ultima ratio in case of traumatic distal duodenal perforation facilitating successful EndoVAC® treatment: A case report

INTRODUCTION

During damage control surgery for blunt abdominal traumata simultaneous duodenal perforations can be missed making secondary sufficient surgical treatment challenging. Endoluminal vacuum (EndoVAC™) therapy has been shown to be a revolutionary option but has anatomical and technical limits.

PRESENTATION OF THE CASE

A 59-year old man with hemorrhagic shock due to rupture of the mesenteric root after blunt abdominal trauma received damage control treatment. Within a scheduled second-look, perforation of the posterior duodenal wall was identified. Due to local and systemic conditions, further surgical treatment was limited. Decision for endoscopic treatment was made but proved to be difficult due to the distal location. Finally, double-barreled jejunal stoma was created for transstomal EndoVAC™ treatment. Complete leakage healing was achieved and jejunostomy reversal followed subsequently.

DISCUSSION

During damage control surgery simultaneous bowel injuries can be missed leading to life-threatening complications with limited surgical options. EndoVAC™ treatment is an option for gastrointestinal perforations but has anatomical limitations that can be sufficiently shifted by a transstomal approach for intestinal leakage.

CONCLUSION

In trauma related laparotomy complete mobilization of the duodenum is crucial. As ultima ratio, transstomal EndoVAC™ is a safe and feasible option and can be considered for similar cases.

Do iatrogenic serosal injuries result in small bowel perforation in a rabbit model?

BACKGROUND

Surgical dogma dictates that serosal injuries should be repaired during laparotomy as these injuries may result in localised areas of bowel ischaemia and may perforate. No study has investigated whether there is a correlation between the extent of serosal injuries and the risk for perforation under normal physiological conditions. We hypothesized that small bowel serosal injuries do not result in early or late perforation at physiological intraluminal pressures regardless of their size.

METHOD

An in-vivo rabbit small bowel serosal injury model was developed and two experiments were conducted. The first - to determine whether and at which pressures various lengths and circumferences of serosal injuries in small bowel result in immediate bowel perforation - was performed infusing saline into isolated bowel segments with or without a variety of serosal injuries. In the second study - to determine whether or not serosal injuries result in delayed perforation - a range of injuries was created in rabbits and the effect assessed at re-laparotomy 5 days after the creation of the injury.

RESULTS

No perforations were observed at the site of serosal injuries at physiological intraluminal pressures. Perforations occurred at 43.7+ 18.6 cmH₂O, 23.3+ 14.4 cmH₂O, and 24.4+ 23.9 cmH₂O for controls, 4 cm long and 100% circumference serosal injuries respectively (p-value = 0.18 for various lengths and 0.71 for various circumferences). No serosal injuries perforated within 72 or 120 hours after creation.

CONCLUSION

Small bowel serosal injuries do not perforate or leak at physiological intraluminal pressures, either at the time of creation or up to 120 hours thereafter.

Cardiovascular risk outcome and program evaluation of a cluster randomised controlled trial of a community-based, lay peer led program for people with diabetes

Background

The 2013 Global Burden of Disease Study demonstrated the increasing burden of diabetes and the challenge it poses to the health systems of all countries. The chronic and complex nature of diabetes requires active self-management by patients in addition to clinical management in order to achieve optimal glycaemic control and appropriate use of available clinical services. This study is an evaluation of a “real world” peer support program aimed at improving the control and management of type 2 diabetes (T2DM) in Australia.

Methods

The trial used a randomised cluster design with a peer support intervention and routine care control arms and 12-month follow up. Participants in both arms received a standardised session of self-management education at baseline. The intervention program comprised monthly community-based group meetings over 12 months led by trained peer supporters and active encouragement to use primary health care and other community resources and supports related to diabetes. Clinical, behavioural and other measures were collected at baseline, 6 and 12 months. The primary outcome was the predicted 5 year cardiovascular disease risk using the United Kingdom Prospective Diabetes Study (UKPDS) Risk Equation at 12 months. Secondary outcomes included clinical measures, quality of life, measures of support, psychosocial functioning and lifestyle measures.

Results

Eleven of 12 planned groups were successfully implemented in the intervention arm. Both the usual care and the intervention arms demonstrated a small reduction in 5 year UKPDS risk and the mean values for biochemical and anthropometric outcomes were close to target at 12 months. There were some small positive changes in self-management behaviours.

Conclusions

The positive changes in self-management behaviours among intervention participants were not sufficient to reduce cardiovascular risk, possibly because approximately half of the study participants already had quite well controlled T2DM at baseline. Future research needs to address how to enhance community based programs so that they reach and benefit those most in need of resources and supports to improve metabolic control and associated clinical outcomes.

Trial registration

Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12609000469213. Registered 16 June 2009.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3538-3) contains supplementary material, which is available to authorized users.

[Are emergency physicians influenced by nonmedical aspects in their choice of the hospital : Observations in 280 victims of out-of-hospital cardiac arrest in times of hospital alliances]

INTRODUCTION

Emergency physicians are responsible for the out-of-hospital treatment of victims from out-of-hospital cardiac arrest (OHCA), not only with regard on the medical treatment, but also in terms of the choice of the most suitable hospital. We therefore wanted to determine whether nonmedical processes such as hospital alliances lead to changing rates of hospital admissions of patients following OHCA.

MATERIALS AND METHODS

All patients who were admitted in our hospital following OHCA between 1 January 2008 and 30 June 2015 were identified and their data were anonymously stored in a central database. Afterward, we divided the study period into three periods: (1) the period prior to the publication of the ERC guidelines 2010, (2) the period after the publication of the ERC guidelines 2010, and (3) the period after a contract for hospital alliances with another hospital in town was signed.

RESULTS

Of the 280 OHCA victims, we could analyze the emergency physician's reports of 238 victims from nontraumatic OHCA; there were 143 men (60.1 %) and 95 women (39.9 %) with an age of 69.1 ± 13.7 years. Following the changes in the guidelines in 2010, we observed a 42.8 % increase of hospital admissions from 2.15 admissions per month to 3.07 in period 2 following OHCA compared to period 1. After signing of the hospital alliance, there was an additional increase of 42.3 % to an average of 4.37 hospital admissions per month.

DISCUSSION AND CONCLUSION

According to our data, it might be possible that not only medical influences (e.g., changes in the guidelines) but also nonmedical aspects (e.g., hospital alliances) might influence the choice of hospital for the further treatment of victims from OHCA.

A Prospective, Placebo-Controlled Pilot Evaluation of the Effect of Omeprazole on Serum Calcium, Magnesium, Cobalamin, Gastrin Concentrations, and Bone in Cats

BACKGROUND

Chronic proton pump inhibitor administration has been associated with electrolyte and cobalamin deficiency, disrupted bone homeostasis, hypergastrinemia, and rebound acid hypersecretion in humans. It is unknown if this occurs in cats.

OBJECTIVES

Prolonged oral omeprazole results in altered bone mineral density or content, serum calcium, magnesium, cobalamin, and gastrin concentrations in healthy cats.

ANIMALS

Six healthy adult DSH cats.

METHODS

In a within subjects, before and after design, cats received placebo followed by omeprazole (0.83-1.6 mg/kg PO q12h) for 60 days each. Analysis of serum calcium, magnesium, cobalamin, and gastrin concentrations was performed on days 0, 30, and 60. Bone density and content were evaluated on days 0 and 60 of each intervention. Continuous data were analyzed using a two-way ANOVA (α = 0.006). On day 60 of omeprazole administration, continuous intragastric pH monitoring was performed in 2 cats to evaluate the effects of abrupt withdrawal of omeprazole.

RESULTS

No significant changes were detected between treatments for any variables, except serum gastrin, which was significantly higher during omeprazole treatment in comparison to placebo (P = 0.002). Evidence of gastric hyperacidity was seen in both cats in which intragastric pH monitoring was performed following cessation of omeprazole.

CONCLUSIONS AND CLINICAL IMPORTANCE

Although further studies with larger populations of cats will be needed to draw any definitive conclusions, these preliminary results suggest that prolonged PPI treatment results in hypergastrinemia and abrupt PPI withdrawal might result in RAH in cats.

Growth in children with pulmonary arterial hypertension: a longitudinal retrospective multiregistry study

BACKGROUND

To enable adequate interpretation of growth measurements in the management of children with pulmonary arterial hypertension (PAH), we assessed growth and its associated determinants in children with PAH.

METHODS

We did a retrospective longitudinal study of height and body-mass index in reference to WHO growth standards by pooling data from four contemporary prospective registries of paediatric PAH representing 53 centres in 19 countries. The main outcome measures were median height for age and body-mass index for age percentiles and longitudinal deviation of height for age and body-mass index for age Z scores from WHO standards.

FINDINGS

601 children were followed up for a median of 2·9 years (IQR 1·5-4·4). Baseline median height for age percentile was 26 (IQR 4-54) and baseline median body-mass index for age percentile was 41 (IQR 12-79). Mean height for age Z score was significantly lower than the reference (-0·81, 95% CI -0·93 to -0·69; p<0·0001), as was body-mass index for age Z score (-0·12, -0·25 to -0·01; p=0·047). Height for age Z score was particularly decreased in young patients (aged ≤5 years) with idiopathic or hereditary PAH and in all patients with PAH associated with congenital heart disease. Although Z scores increased in some patients and decreased in others, we detected no significant trend in height for age Z score (p=0·57) or body-mass index for age Z score (p=0·48) before taking account of covariates. Multivariable linear mixed effects modelling showed that age, cause of PAH, ex-prematurity, WHO functional class, trisomy 21, and time since diagnosis were associated with height for age Z score, whereas age, ethnicity, and trisomy 21 were associated with body-mass index for age Z score. A favourable WHO functional class course was independently associated with increases in height for age Z score.

INTERPRETATION

PAH is associated with impaired growth, especially in younger children and those with pulmonary arterial hypertension associated with congenital heart disease. The degree of impairment is independently associated with cause of PAH and comorbidities, but also with disease severity and duration. Because a favourable clinical course was associated with catch-up growth, height for age could serve as an additional and globally available clinical parameter to monitor patients' clinical condition.

FUNDING

Actelion Pharmaceuticals.