19 research outputs found

    ‘Bouncing back’ from subclinical malaria:Inflammation and erythrocytosis after resolution of P. falciparum infection in Gambian children

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    Recent malaria is associated with an increased risk of systemic bacterial infection. The aetiology of this association is unclear but malaria-related haemolysis may be one contributory factor. To characterise the physiological consequences of persistent and recently resolved malaria infections and associated haemolysis, 1650 healthy Gambian children aged 8–15 years were screened for P. falciparum infection (by 18sRNA PCR) and/or anaemia (by haematocrit) at the end of the annual malaria transmission season (t1). P. falciparum-infected children and children with moderate or severe anaemia (haemoglobin concentration < 11g/dl) were age matched to healthy, uninfected, non-anaemic controls and screened again 2 months later (t2). Persistently infected children (PCR positive at t1 and t2) had stable parasite burdens and did not differ significantly haematologically or in terms of proinflammatory markers from healthy, uninfected children. However, among persistently infected children, IL-10 concentrations were positively correlated with parasite density suggesting a tolerogenic response to persistent infection. By contrast, children who naturally resolved their infections (positive at t1 and negative at t2) exhibited mild erythrocytosis and concentrations of pro-inflammatory markers were raised compared to other groups of children. These findings shed light on a ‘resetting’ and potential overshoot of the homeostatic haematological response following resolution of malaria infection. Interestingly, the majority of parameters tested were highly heterogeneous in uninfected children, suggesting that some may be harbouring cryptic malaria or other infections

    Cardiac sodium channel inhibition by lamotrigine: in vitro characterization and clinical implications

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    Lamotrigine, approved for use as an antiseizure medication (ASM) as well as the treatment of bipolar disorder, inhibits sodium channels in the brain to reduce repetitive neuronal firing and pathological release of glutamate. The shared homology of sodium channels and lack of selectivity associated with channel blocking agents can cause slowing of cardiac conduction and increased proarrhythmic potential. The Vaughan-Williams classification system differentiates sodium channel blockers using biophysical properties of binding. As such, Class Ib inhibitors including mexiletine do not slow cardiac conduction as measured by the electrocardiogram (ECG), at therapeutically relevant exposure. Our goal was to characterize the biophysical properties of NaV 1.5 block and to support the observed clinical safety of lamotrigine. We used HEK-293 cells stably expressing the hNaV 1.5 channel and voltage clamp electrophysiology to quantify the potency (IC50 ) against peak and late channel current, on-/off-rate binding kinetics, voltage-dependence and tonic block of the cardiac sodium channel by lamotrigine; and compared to clinically relevant Class Ia (quinidine), Ib (mexiletine) and Ic (flecainide) inhibitors. Lamotrigine blocked peak and late NaV 1.5 current at therapeutically relevant exposure, with rapid kinetics and biophysical properties similar to the Class Ib inhibitor mexiletine. However, no clinically meaningful prolongation in QRS or PR interval was observed in healthy subjects in a new analysis of a previously reported thorough QT clinical trial (SCA104648). In conclusion, the weak NaV 1.5 block and rapid kinetics do not translate into clinically relevant conduction slowing at therapeutic exposure and support the clinical safety of lamotrigine in patients suffering from epilepsy and bipolar disorder

    Towards an Interoperable Ecosystem of Research Cohort and Real-world Data Catalogues Enabling Multi-center Studies

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    Objectives : Existing individual-level human data cover large populations on many dimensions such as lifestyle, demography, laboratory measures, clinical parameters, etc. Recent years have seen large investments in data catalogues to FAIRify data descriptions to capitalise on this great promise, i.e. make catalogue contents more Findable, Accessible, Interoperable and Reusable. However, their valuable diversity also created heterogeneity, which poses challenges to optimally exploit their richness. Methods : In this opinion review, we analyse catalogues for human subject research ranging from cohort studies to surveillance, administrative and healthcare records. Results : We observe that while these catalogues are heterogeneous, have various scopes, and use different terminologies, still the underlying concepts seem potentially harmonizable. We propose a unified framework to enable catalogue data sharing, with catalogues of multi-center cohorts nested as a special case in catalogues of real-world data sources. Moreover, we list recommendations to create an integrated community of metadata catalogues and an open catalogue ecosystem to sustain these efforts and maximise impact. Conclusions : We propose to embrace the autonomy of motivated catalogue teams and invest in their collaboration via minimal standardisation efforts such as clear data licensing, persistent identifiers for linking same records between catalogues, minimal metadata ‘common data elements’ using shared ontologies, symmetric architectures for data sharing (push/pull) with clear provenance tracks to process updates and acknowledge original contributors. And most importantly, we encourage the creation of environments for collaboration and resource sharing between catalogue developers, building on international networks such as OpenAIRE and research data alliance, as well as domain specific ESFRIs such as BBMRI and ELIXIR

    Effects of ACE inhibitors and angiotensin receptor blockers: protocol for a UK cohort study using routinely collected electronic health records with validation against the ONTARGET trial.

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    INTRODUCTION: Cardiovascular disease is a leading cause of death globally, responsible for nearly 18 million deaths worldwide in 2017. Medications to reduce the risk of cardiovascular events are prescribed based on evidence from clinical trials which explore treatment effects in an indicated sample of the general population. However, these results may not be fully generalisable because of trial eligibility criteria that generally restrict to younger patients with fewer comorbidities. Therefore, evidence of effectiveness of medications for groups underrepresented in clinical trials such as those aged ≥75 years, from ethnic minority backgrounds or with low kidney function may be limited.Using individual anonymised data from the Ongoing Telmisartan Alone and the Ramipril Global Endpoint Trial (ONTARGET) trial, in collaboration with the original trial investigators, we aim to investigate clinical trial replicability within a real-world setting in the area of cardiovascular disease. If the original trial results are replicable, we will estimate treatment effects and risk in groups underrepresented and excluded from the original clinical trial. METHODS AND ANALYSIS: We will develop a cohort analogous to the ONTARGET trial within the Clinical Practice Research Datalink between 1 January 2001 and 31 July 2019 using the trial eligibility criteria and propensity score matching. The primary outcome is a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke and hospitalisation for congestive heart failure. If results from the cohort study fall within pre-specified limits, we will expand the cohort to include under represented and excluded groups. ETHICS AND DISSEMINATION: Ethical approval has been granted by the London School of Hygiene & Tropical Medicine Ethics Committee (Ref: 22658). The study has been approved by the Independent Scientific Advisory Committee of the UK Medicines and Healthcare Products Regulatory Agency (protocol no. 20_012). Access to the individual patient data from the ONTARGET trial was obtained by the trial investigators. Findings will be submitted to peer-reviewed journals and presented at conferences

    Free combination of dutasteride plus tamsulosin for the treatment of benign prostatic hyperplasia in South Korea: analysis of drug utilization and adverse events using the National Health Insurance Review and Assessment Service database

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    Abstract Objective To assess the use and safety of free combination therapy (dutasteride and tamsulosin), dutasteride monotherapy, or tamsulosin monotherapy in patients with benign prostatic hyperplasia (BPH). Methods This non-interventional retrospective cohort study used claims data from the Korea Health Insurance Review and Assessment-National Patient Sample database. Patients with BPH ≥ 40years of age receiving combination therapy (dutasteride 0.5mg and tamsulosin 0.4mg daily) or dutasteride 0.5mg, or tamsulosin 0.4mg daily dose between 2012 and 2017 were included. The frequency, duration of treatment and risk of any adverse event (AE) or serious AE (SAE) was compared for combination therapy versus each monotherapy using non-inferiority testing. Results Of 14,755 eligible patients, 1529 (10.4%) received combination therapy, 6660 (45.1%) dutasteride monotherapy, and 6566 (44.5%) tamsulosin monotherapy. The proportion of patients treated with combination therapy exceeded the pre-specified 3% threshold for frequent use. Safety results indicated a similar risk of any AE and SAE irrespective of treatment group. The adjusted relative risk for any AE over the treatment observation period comparing combination therapy with dutasteride monotherapy was 1.07 (95% confidence interval [CI] 1.03, 1.12), and with tamsulosin monotherapy was 0.98 (95% CI 0.95, 1.02) demonstrating non-inferiority. The adjusted relative risk for any SAE was 1.07 (95% CI 0.66, 1.74) and 0.90 (95% CI 0.56, 1.45), compared with dutasteride and tamsulosin monotherapy, respectively. Although the SAE results did not statistically demonstrate non-inferiority of combination therapy based on pre-specified margins, the 95% CI for the risk ratio estimates included the null with a lower limit below the non-inferiority margins, indicating no meaningful differences in SAE risk between groups. Absolute SAE risks were low. Conclusion Combination therapy with dutasteride and tamsulosin is frequently used in real-world practice in South Korea for treatment of BPH and demonstrates a safety profile similar to either monotherapy

    From Inception to ConcePTION: Genesis of a Network to Support Better Monitoring and Communication of Medication Safety During Pregnancy and Breastfeeding

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    In 2019, the Innovative Medicines Initiative (IMI) funded the ConcePTION project—Building an ecosystem for better monitoring and communicating safety of medicines use in pregnancy and breastfeeding: validated and regulatory endorsed workflows for fast, optimised evidence generation—with the vision that there is a societal obligation to rapidly reduce uncertainty about the safety of medication use in pregnancy and breastfeeding. The present paper introduces the set of concepts used to describe the European data sources involved in the ConcePTION project and illustrates the ConcePTION Common Data Model (CDM), which serves as the keystone of the federated ConcePTION network. Based on data availability and content analysis of 21 European data sources, the ConcePTION CDM has been structured with six tables designed to capture data from routine healthcare, three tables for data from public health surveillance activities, three curated tables for derived data on population (e.g., observation time and mother-child linkage), plus four metadata tables. By its first anniversary, the ConcePTION CDM has enabled 13 data sources to run common scripts to contribute to major European projects, demonstrating its capacity to facilitate effective and transparent deployment of distributed analytics, and its potential to address questions about utilization, effectiveness, and safety of medicines in special populations, including during pregnancy and breastfeeding, and, more broadly, in the general population

    Risk of ischaemic cardiovascular events from selective cyclooxygenase-2 inhibitors in osteoarthritis

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    Purpose Most previous observational studies assessing cardiovascular risk associated with Cox‐2 inhibitors (Cox‐2is) used a case control approach, limiting the assessment of absolute risk by disease group and effect of duration of exposure. We conducted a retrospective cohort study in patients with osteoarthritis. Methods Using the Life‐link US claims database, all subjects had at least five years history in the database. Exposure was defined as the first chronic period of Cox‐2i (celecoxib, rofecoxib or valdecoxib) or naproxen use. Non‐users and non‐chronic users of non‐steroidal anti‐inflammatory drug (NSAID)/Cox‐2i within the osteoarthritis cohort served as the reference. The primary outcome was myocardial infarction and ischaemic stroke. Results A cohort of 16 580 subjects were chronically exposed to celecoxib, 9800 received rofecoxib, 2907 received naproxen and 51 539 were non‐chronically exposed controls. With a median follow up of 506 days, there were 2116 ischaemic events for the entire cohort. The strongest predictors of AMI/ ischaemic stroke risk were history of ischaemic stroke (HR 2.34, 2.12–2.59) and age 65+ years (HR 2.28, 2.07–2.52). For rofecoxib, (HR 1.25,1.04–1.50), the attributable risk varied from 3 per 1000 patients years in individuals aged under 65 years with no history of CVD to 19 per 1000 patients years in older individuals with a history of CVD. The hazard ratios did not change over time. Celecoxib and naproxen were not associated with increased risks. Conclusions The attributable risk for rofecoxib varied substantially with the underlying cardiovascular risk profile, being lower in clinical trial than in clinical practice populations. Copyright © 2008 John Wiley & Sons, Ltd

    Prevalent new user designs: a literature review of current implementation practice

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    PURPOSE: Prevalent new user (PNU) designs extend the active comparator new user design by allowing for the inclusion of initiators of the study drug who were previously on a comparator treatment. We performed a literature review summarising current practice. METHODS: PubMed was searched for studies applying the PNU design since its proposal in 2017. The review focused on three components. Firstly, we extracted information on the overall study design, including the database used. We summarised information on implementation of the PNU design, including key decisions relating to exposure set definition and estimation of time-conditional propensity scores. Finally, we reviewed the analysis strategy of the matched cohort. RESULTS: Nineteen studies met the criteria for inclusion. Most studies (73%) implemented the PNU design in electronic health record or registry databases, with the remaining using insurance claims databases. Of 15 studies including a class of prevalent users, 40% deviated from the original exposure set definition proposals in favour of a more complex definition. Four studies did not include prevalent new users but used other aspects of the PNU framework. Several studies lacked details on exposure set definition (n = 2), time-conditional propensity score model (n = 2) or integration of complex analytical techniques, such as the high-dimensional propensity score algorithm (n = 3). CONCLUSION: PNU designs have been applied in a range of therapeutic and disease areas. However, to encourage more widespread use of this design and help shape best practice, there is a need for improved accessibility, specifically through the provision of analytical code alongside guidance to support implementation and transparent reporting

    Towards an Interoperable Ecosystem of Research Cohort and Real-world Data Catalogues Enabling Multi-center Studies

    No full text
    OBJECTIVES: Existing individual-level human data cover large populations on many dimensions such as lifestyle, demography, laboratory measures, clinical parameters, etc. Recent years have seen large investments in data catalogues to FAIRify data descriptions to capitalise on this great promise, i.e. make catalogue contents more Findable, Accessible, Interoperable and Reusable. However, their valuable diversity also created heterogeneity, which poses challenges to optimally exploit their richness. METHODS: In this opinion review, we analyse catalogues for human subject research ranging from cohort studies to surveillance, administrative and healthcare records. RESULTS: We observe that while these catalogues are heterogeneous, have various scopes, and use different terminologies, still the underlying concepts seem potentially harmonizable. We propose a unified framework to enable catalogue data sharing, with catalogues of multi-center cohorts nested as a special case in catalogues of real-world data sources. Moreover, we list recommendations to create an integrated community of metadata catalogues and an open catalogue ecosystem to sustain these efforts and maximise impact. CONCLUSIONS: We propose to embrace the autonomy of motivated catalogue teams and invest in their collaboration via minimal standardisation efforts such as clear data licensing, persistent identifiers for linking same records between catalogues, minimal metadata 'common data elements' using shared ontologies, symmetric architectures for data sharing (push/pull) with clear provenance tracks to process updates and acknowledge original contributors. And most importantly, we encourage the creation of environments for collaboration and resource sharing between catalogue developers, building on international networks such as OpenAIRE and research data alliance, as well as domain specific ESFRIs such as BBMRI and ELIXIR
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