13 research outputs found
The Persisting Burden of Intracerebral Haemorrhage: Can Effective Treatments Be Found?
Colin Josephson, Rustam Al-Shahi Salman, and colleagues discuss the effectiveness of treatments for intracerebral haemorrhage
Absolute risk and predictors of the growth of acute spontaneous intracerebral haemorrhage: a systematic review and meta-analysis of individual patient data.
Background Intracerebral haemorrhage growth is associated with poor clinical outcome and is a therapeutic target for improving outcome. We aimed to determine the absolute risk and predictors of intracerebral haemorrhage growth, develop and validate prediction models, and evaluate the added value of CT angiography. Methods In a systematic review of OVID MEDLINE—with additional hand-searching of relevant studies' bibliographies— from Jan 1, 1970, to Dec 31, 2015, we identified observational cohorts and randomised trials with repeat scanning protocols that included at least ten patients with acute intracerebral haemorrhage. We sought individual patient-level data from corresponding authors for patients aged 18 years or older with data available from brain imaging initially done 0·5–24 h and repeated fewer than 6 days after symptom onset, who had baseline intracerebral haemorrhage volume of less than 150 mL, and did not undergo acute treatment that might reduce intracerebral haemorrhage volume. We estimated the absolute risk and predictors of the primary outcome of intracerebral haemorrhage growth (defined as >6 mL increase in intracerebral haemorrhage volume on repeat imaging) using multivariable logistic regression models in development and validation cohorts in four subgroups of patients, using a hierarchical approach: patients not taking anticoagulant therapy at intracerebral haemorrhage onset (who constituted the largest subgroup), patients taking anticoagulant therapy at intracerebral haemorrhage onset, patients from cohorts that included at least some patients taking anticoagulant therapy at intracerebral haemorrhage onset, and patients for whom both information about anticoagulant therapy at intracerebral haemorrhage onset and spot sign on acute CT angiography were known. Findings Of 4191 studies identified, 77 were eligible for inclusion. Overall, 36 (47%) cohorts provided data on 5435 eligible patients. 5076 of these patients were not taking anticoagulant therapy at symptom onset (median age 67 years, IQR 56–76), of whom 1009 (20%) had intracerebral haemorrhage growth. Multivariable models of patients with data on antiplatelet therapy use, data on anticoagulant therapy use, and assessment of CT angiography spot sign at symptom onset showed that time from symptom onset to baseline imaging (odds ratio 0·50, 95% CI 0·36–0·70; p<0·0001), intracerebral haemorrhage volume on baseline imaging (7·18, 4·46–11·60; p<0·0001), antiplatelet use (1·68, 1·06–2·66; p=0·026), and anticoagulant use (3·48, 1·96–6·16; p<0·0001) were independent predictors of intracerebral haemorrhage growth (C-index 0·78, 95% CI 0·75–0·82). Addition of CT angiography spot sign (odds ratio 4·46, 95% CI 2·95–6·75; p<0·0001) to the model increased the C-index by 0·05 (95% CI 0·03–0·07). Interpretation In this large patient-level meta-analysis, models using four or five predictors had acceptable to good discrimination. These models could inform the location and frequency of observations on patients in clinical practice, explain treatment effects in prior randomised trials, and guide the design of future trials
Improving our understanding of the in vivo modelling of psychotic disorders: a systematic review and meta-analysis
Psychotic disorders represent a severe category of mental disorders affecting about one
percent of the population. Individuals experience a loss or distortion of contact with reality
alongside other symptoms, many of which are still not adequately managed using existing
treatments. While animal models of these disorders could offer insights into these disorders
and potential new treatments, translation of this knowledge has so far been poor in terms of
informing clinical trials and practice. The aim of this project was to improve our
understanding of these pre-clinical studies and identify potential weaknesses underlying
translational failure.
I carried out a systematic search of the literature to provide an unbiased summary of
publications reporting animal models of schizophrenia and other psychotic disorders. From
these publications, data were extracted to quantify aspects of the field including reported
quality of studies, study characteristics and behavioural outcome data. The latter of these
data were then used to calculate estimates of efficacy using random-effects meta-analysis.
Having identified 3847 publications of relevance, including 852 different methods used to
induce the model, over 359 different outcomes tested in them and almost 946 different
treatments reported to be administered. I show that a large proportion of studies use simple
pharmacological interventions to induce their models of these disorders, despite the
availability of models using other interventions that are arguably of higher translational
relevance. I also show that the reported quality of these studies is low, and only 22% of
studies report taking measures to reduce the risk of biases such as randomisation and
blinding, which has been shown to affect the reliability of results drawn.
Through this work it becomes apparent that the literature is incredibly vast for studies looking
at animal models of psychotic disorders and that some of the relevant work potentially
overlaps with studies describing other conditions. This means that drawing reliable
conclusions from these data is affected by what is made available in the literature, how it is
reported and identified in a search and the time that it takes to reach these conclusions. I
introduce the idea of using computer-assisted tools to overcome one of these problems in
the long term.
Translation of results from studies looking at animals modelling uniquely-human psychotic
disorders to clinical successes might be improved by better reporting of studies including
publishing of all work carried out, labelling of studies more uniformly so that it is identifiable,
better reporting of study design including improving on reporting of measures taken to
reduce the risk of bias and focusing on models with greater validity to the human condition
Prospective, multicentre study of screening, investigation and management of hyponatraemia after subarachnoid haemorrhage in the UK and Ireland
Background: Hyponatraemia often occurs after subarachnoid haemorrhage (SAH). However, its clinical significance and optimal management are uncertain. We audited the screening, investigation and management of hyponatraemia after SAH. Methods: We prospectively identified consecutive patients with spontaneous SAH admitted to neurosurgical units in the United Kingdom or Ireland. We reviewed medical records daily from admission to discharge, 21 days or death and extracted all measurements of serum sodium to identify hyponatraemia (<135 mmol/L). Main outcomes were death/dependency at discharge or 21 days and admission duration >10 days. Associations of hyponatraemia with outcome were assessed using logistic regression with adjustment for predictors of outcome after SAH and admission duration. We assessed hyponatraemia-free survival using multivariable Cox regression. Results: 175/407 (43%) patients admitted to 24 neurosurgical units developed hyponatraemia. 5976 serum sodium measurements were made. Serum osmolality, urine osmolality and urine sodium were measured in 30/166 (18%) hyponatraemic patients with complete data. The most frequently target daily fluid intake was >3 L and this did not differ during hyponatraemic or non-hyponatraemic episodes. 26% (n/N=42/164) patients with hyponatraemia received sodium supplementation. 133 (35%) patients were dead or dependent within the study period and 240 (68%) patients had hospital admission for over 10 days. In the multivariable analyses, hyponatraemia was associated with less dependency (adjusted OR (aOR)=0.35 (95% CI 0.17 to 0.69)) but longer admissions (aOR=3.2 (1.8 to 5.7)). World Federation of Neurosurgical Societies grade I–III, modified Fisher 2–4 and posterior circulation aneurysms were associated with greater hazards of hyponatraemia. Conclusions: In this comprehensive multicentre prospective-adjusted analysis of patients with SAH, hyponatraemia was investigated inconsistently and, for most patients, was not associated with changes in management or clinical outcome. This work establishes a basis for the development of evidence-based SAH-specific guidance for targeted screening, investigation and management of high-risk patients to minimise the impact of hyponatraemia on admission duration and to improve consistency of patient care
Identification of hydrogen-sulfide releasing compounds as novel antiresorptive and antitumour agents
Hydrogen sulphide-releasing diclofenac derivatives inhibit breast cancer-induced osteoclastogenesis in vitro and prevent osteolysis ex vivo
BACKGROUND AND PURPOSE Hydrogen sulphide (H(2) S) and prostaglandins are both involved in inflammation, cancer and bone turnover, and non-steroidal anti-inflammatory drugs (NSAIDs) and H(2) S donors exhibit anti-inflammatory and anti-tumour properties. H(2) S-releasing diclofenac (S-DCF) derivatives are a novel class of NSAIDs combining the properties of a H(2) S donor with those of a conventional NSAID. EXPERIMENTAL APPROACH We studied the effects of the S-DCF derivatives ACS15 and ACS32 on osteoclast and osteoblast differentiation and activity in vitro, human and mouse breast cancer cells support for osteoclast formation and signalling in vitro, and osteolysis ex vivo. KEY RESULTS The S-diclofenac derivatives ACS15 and ACS32 inhibited the increase in osteoclast formation induced by human MDA-MB-231 and MCF-7 and mouse 4T1 breast cancer cells without affecting breast cancer cell viability. Conditioned media from human MDA-MB-231 cells enhanced I\u3baB phosphorylation and osteoclast formation and these effects were significantly inhibited following treatment by ACS15 and ACS32, whereas the parent compound diclofenac had no effects. ACS15 and ACS32 inhibited receptor activator of NF\u3baB ligand-induced osteoclast formation and resorption, and caused caspase-3 activation and apoptosis in mature osteoclasts via a mechanism dependent on IKK/NF\u3baB inhibition. In calvaria organ culture, human MDA-MB-231 cells caused osteolysis, and this effect was completely prevented following treatment with ACS15 and ACS32. CONCLUSIONS AND IMPLICATIONS S-diclofenac derivatives inhibit osteoclast formation and activity, suppress breast cancer cell support for osteoclastogenesis and prevent osteolysis. This suggests that H(2) S-releasing diclofenac derivatives exhibit anti-resorptive properties, which might be of clinical value in the treatment of osteolytic bone disease