The individual and combined impacts of pre-existing diabetes and dementia on ischemic stroke outcomes: a registry-based cohort study.

BACKGROUND: Individually, diabetes mellitus and dementia are associated with poorer outcomes after stroke. However, the combined impact of these pre-existing factors on acute ischemic stroke (AIS) outcomes has not been examined. METHODS: All consecutive patients with AIS admitted to Norfolk and Norwich University Hospitals between 2003 and 2016 (catchment population ~ 900,000) were divided into four groups: those with neither diabetes nor dementia (reference), with diabetes without dementia, with dementia without diabetes, and with both co-morbidities. In-hospital mortality, length of hospital stay (LoS), and disability outcomes were analysed using logistic regressions. Post-discharge mortality and recurrence were assessed using Cox regressions. Additionally, interaction terms were added to the models for the short-term outcomes and long-term mortality to test for synergistic effects of diabetes and dementia. Models were adjusted for age, sex, Oxfordshire Community Stroke Project classification, comorbidities, hematological and biochemical measures, and antithrombotic medications. RESULTS: The cohort was 10,812 patients with 52% females and a median age of 80. The median follow-up was 3.8 years for stroke recurrence and 5.5 years for mortality. No significant differences between the four groups existed for in-hospital mortality and post-stroke disability. Patients with dementia had significantly longer LoS (OR 2.25 [95% CI: 1.34-3.77] and 1.31 [1.02-1.68] with and without diabetes, respectively). Patients with both comorbidities had the highest risk of stroke recurrence (HR 2.06 [1.12-3.77]), followed by those with only dementia (1.59 [1.15-2.20]) and only diabetes (1.25 [1.06-1.49]). Similarly, the patient group with both diabetes and dementia had the highest long-term mortality risk (1.76 [1.33-2.37]). The hazard ratios for patients with only dementia and only diabetes were 1.71 [1.46-2.01] and 1.19 [1.08-1.32], respectively. No significant interactions were seen between diabetes and dementia with regards to their effects on the outcomes. CONCLUSION: Individual and cumulative impacts of the two conditions on long-term mortality and stroke recurrence were notable. However, no synergistic impact of the two comorbidities were seen on the stroke outcomes tested in our study. Therefore, tailoring the management of stroke patients based on additional requirements associated with each pre-existing condition will be more impactful towards improving outcomes.

Infective endocarditis is associated with worse outcomes in stroke: A Thailand National Database Study.

BACKGROUND: There is lack of data on the association between infective endocarditis (IE) and outcomes of mortality and complications in stroke. We aimed to compare characteristics and outcomes of stroke patients with and without IE. METHODS: We retrospectively examined the above association using data obtained from an insurance database which covers ~75% of the Thai population. All hospitalised strokes between 8 January 2003 and 31 December 2013 were included in the current study. Characteristics and outcomes were compared between stroke patients with or without IE, and then between two main stroke types. Multiple logistic regression models including propensity score-matched analyses were constructed to assess study outcomes controlling for age, sex, stroke type and comorbidities. RESULTS: A total of 590 115 stroke patients (mean (SD) age = 64.2 ± 13.7 years; ischaemic = 51.7%; haemorrhagic = 32.6%; undetermined = 15.7%) were included, of whom 2129 (0.36%) had stroke associated with IE. After adjustment, we found that IE was significantly associated with the following complications: arrhythmias (adjusted odds ratio (95% CI) 6.94 (6.29-7.66)), sepsis (1.24 (1.01-1.52)), pneumonia (1.34 (1.17-1.53)), respiratory failure (1.43 (1.24-1.66)) and in-hospital mortality (1.29 (1.13-1.47)) (P for all <.001). Patients with haemorrhagic stroke with IE had poorer outcomes for in-hospital mortality and respiratory failure compared with their counterparts with ischaemic stroke. Propensity score-matched analysis showed similar results. CONCLUSIONS: Our results suggest that stroke patients with IE differ from that of the general stroke population and these patients have worse outcomes. Future studies are needed to determine the best treatment strategies for stroke patients with IE.

Individual and Combined Impact of Heart Failure and Atrial Fibrillation on Ischemic Stroke Outcomes.

Background and Purpose- We aimed to determine individual and combined effects of atrial fibrillation (AF) and heart failure (HF) on acute ischemic stroke outcomes: in-hospital mortality, length-of-stay, and poststroke disability; long-term mortality and stroke recurrence. Methods- Prospective cohort study of patients with acute ischemic stroke admitted to a UK center with a catchment population of ≈900 000 between 2004 and 2016. Exposure groups were patients with neither AF nor HF (reference group), those with AF but without HF, those with HF but without AF, and those with AF+HF. Logistic and Cox regressions were used to model in-hospital and long-term outcomes, respectively. Results- A total of 10 816 patients with a mean age±SD =77.9±12.1 years, 48% male were included. Only 30 (4.9%) of the patients with HF but not AF were anticoagulated at discharge. Both AF (odds ratio, 1.24 [95% CI, 1.07-1.43]), HF (odds ratio, 1.40 [1.10-1.79]), and their combination (odds ratio, 2.23 [1.83-2.72]) were associated with increased odds of in-hospital mortality. All 3 exposure groups were associated with increased length-of-stay, while only AF predicted increased disability (1.36 [1.12-1.64]). Patients were followed for a median of 5.5 and 3.7 years for mortality and recurrence, respectively. Long-term mortality was associated with AF (hazard ratio, 1.45 [95% CI, 1.33-1.59]), HF (2.07 [1.83-2.36]), and their combination (2.20 [1.96-2.46]). Recurrent stroke was associated with AF 1.50 (1.26-1.78), HF (1.33 [1.01-1.75]), and AF with HF (1.62 [1.28-2.07]). Conclusions- The AF-associated excess risk of stroke recurrence was independent of comorbid HF. HF without AF was also associated with a significant risk of recurrence. Anticoagulation for secondary stroke prevention in patients with HF without AF may require further evaluation in a clinical trial setting.

Myocardial infarction after acute ischaemic stroke: Incidence, mortality and risk factors.

OBJECTIVES: To determine the risk factor profiles associated with post-acute ischaemic stroke (AIS) myocardial infarction (MI) over long-term follow-up. METHODS: This observational study includes prospectively identified AIS patients (n = 9840) admitted to a UK regional centre between January 2003 and December 2016 (median follow-up: 4.72 years). Predictors of post-stroke MI during follow-up were examined using logistic and Cox regression models for in-hospital and post-discharge events, respectively. MI incidence was determined using a competing risk non-parametric estimator. The influence of post-stroke MI on mortality was examined using Cox regressions. RESULTS: Mean age (SD) of study participants was 77.3 (12.2) years (48% males). Factors associated with in-hospital MI (OR [95% CI]) were increasing blood glucose (1.80 [1.17-2.77] per 10 mmol/L), total leucocyte count (1.25 [1.01-1.54] per 10 × 109 /L) and CRP (1.05 [1.02-1.08] per 10 mg/L increase). Age (HR [95% CI] = 1.03 [1.01-1.06]), coronary heart disease (1.59 [1.01-2.50]), chronic kidney disease (2.58 [1.44-4.63]) and cancers (1.76 [1.08-2.89]) were associated with incident MI between discharge and one-year follow-up. Age (1.02 [1.00-1.03]), diabetes (1.96 [1.38-2.65]), congestive heart failure (2.07 [1.44-2.99]), coronary heart disease (1.81 [1.31-2.50]), hypertension [1.86 (1.24-2.79)] and peripheral vascular disease (2.25 [1.40-3.63]) were associated with incident MI between 1 and 5 years after discharge. Diabetes (2.01 [1.09-3.72]), hypertension (3.69 [1.44-9.45]) and peripheral vascular disease (2.46 [1.02-5.98]) were associated with incident MI between 5 and 10 years after discharge. Cumulative MI incidence over 10 years was 5.4%. MI during all follow-up periods (discharge-1, 1-5, 5-10 years) was associated with increased risk of death (respective HR [95% CI] = 3.26 [2.51-4.15], 1.96 [1.58-2.42] and 1.92 [1.26-2.93]). CONCLUSIONS: In conclusion, prognosis is poor in post-stroke MI. We highlight a range of potential areas to focus preventative efforts.

Pneumonia and Risk of Serious Adverse Outcomes in Hospitalized Strokes in Thailand.

BACKGROUND: The impact of stroke associated pneumonia (SAP) on stroke complications is not well understood; we aimed to study the association between SAP and adverse outcomes including in-hospital mortality, prolonged length of stay and the risk of developing common serious complications (sepsis, respiratory failure, and convulsions). METHODS: We retrospectively analyzed data from a cohort of 610,668 stroke patients drawn from the Universal Coverage Health Security Scheme (a national insurance database) in Thailand which covers ∼80% of the Thai population. Patients were hospitalized between October 2004 and January 2013. RESULTS: Pneumonia was present in 9.6 % (n = 58,586) of patients. Aspiration pneumonia was present in 6.2% (n = 38,060) and nonaspiration pneumonia in 3.4% (n = 20,526). After adjusting for age, sex, stroke type, and comorbidities, patients with SAP had significantly higher odds of in-hospital mortality (odds ratio [OR] 2.90: 2.83-2.96), long length of stay (OR 13.11: 12.83-13.40), sepsis (OR 8.49: 8.22-8.76), respiratory failure (OR 4.37: 4.27-4.48), and convulsions (OR 2.09: 2.00-2.17). On subanalysis, patients with nonaspiration pneumonia were found to have higher odds of adverse outcomes compared to aspiration pneumonia; the corresponding ORs (95% confidence interval) for above outcomes were 1.25 (1.21-1.30), 2.40 (2.32-2.49), 1.34 (1.28-1.40), 1.80 (1.73-1.88), and 1.19 (1.11-1.28), respectively. CONCLUSIONS: SAP is associated with higher odds of inpatient mortality, long length of stay, and risk of developing serious stroke complications. Nonaspiration pneumonia is associated with significantly higher likelihood of adverse outcomes compared to aspiration pneumonia in this patient population. Early identification and treatment of SAP is vital in reducing adverse outcomes in acute stroke.

Role of tamoxifen in idiopathic gynecomastia: A 10-year prospective cohort study.

BACKGROUND: Idiopathic gynecomastia is a benign breast disorder characterized by overdevelopment of male breast tissue. It can cause discomfort and concern, resulting in patients seeking diagnosis and treatment. We aimed to evaluate the efficacy of tamoxifen therapy in resolving this condition. METHODS: We undertook a prospective cohort study of all male patients who presented to our breast clinic, were diagnosed with primary gynecomastia, and were treated with a trial of tamoxifen 10 mg daily therapy, over a 10-year period from October 2004 to October 2015. All patients underwent routine investigations to exclude secondary causes of gynecomastia. The end point of interest was the complete resolution of gynecomastia. RESULTS: We included 81 patients in this study. The mean age was 42.8 years (SD 19.5 years). Of these, 28.4% were bilateral gynecomastia and 71.6% were unilateral. The majority (87.7%) of cases presented with accompanying mastalgia. Following treatment, 90.1% (n = 73) had a complete response of their gynecomastia with tamoxifen therapy. Only eight patients did not have a complete resolution following tamoxifen therapy, of which two underwent subsequent surgical resection of their symptomatic gynecomastia. CONCLUSION: Our study is the largest to date examining the role of tamoxifen in idiopathic gynecomastia, and our results show approximately nine in every 10 men treated with tamoxifen therapy had successful resolution of their symptoms. We support its use for idiopathic gynecomastia in eligible men following the careful discussion of its risks and benefits.

Closure methods of the appendix stump for complications during laparoscopic appendectomy.

BACKGROUND: Laparoscopic appendectomy is amongst the most common general surgical procedures performed in the developed world. Arguably, the most critical part of this procedure is effective closure of the appendix stump to prevent catastrophic intra-abdominal complications from a faecal leak into the abdominal cavity. A variety of methods to close the appendix stump are used worldwide; these can be broadly divided into traditional ligatures (such as intracorporeal or extracorporeal ligatures or Roeder loops) and mechanical devices (such as stapling devices, clips, or electrothermal devices). However, the optimal method remains unclear. OBJECTIVES: To compare all surgical techniques now used for appendix stump closure during laparoscopic appendectomy. SEARCH METHODS: In June 2017, we searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 6) in the Cochrane Library, MEDLINE Ovid (1946 to 14 June 2017), Embase Ovid (1974 to 14 June 2017), Science Citation Index - Expanded (14 June 2017), China Biological Medicine Database (CBM), the World Health Organization International Trials Registry Platform search portal, ClinicalTrials.gov, Current Controlled Trials, the Chinese Clinical Trials Register, and the EU Clinical Trials Register (all in June 2017). We searched the reference lists of relevant publications as well as meeting abstracts and Conference Proceedings Citation Index to look for additional relevant clinical trials. SELECTION CRITERIA: We included all randomised controlled trials (RCTs) that compared mechanical appendix stump closure (stapler, clips, or electrothermal devices) versus ligation (Endoloop, Roeder loop, or intracorporeal knot techniques) for uncomplicated appendicitis. DATA COLLECTION AND ANALYSIS: Two review authors identified trials for inclusion, collected data, and assessed risk of bias independently. We performed the meta-analysis using Review Manager 5. We calculated the odds ratio (OR) for dichotomous outcomes and the mean difference (MD) for continuous outcomes, with 95% confidence intervals (CIs). MAIN RESULTS: We included eight randomised studies encompassing 850 participants. Five studies compared titanium clips versus ligature, two studies compared an endoscopic stapler device versus ligature, and one study compared an endoscopic stapler device, titanium clips, and ligature. In our analyses of primary outcomes, we found no differences in total complications (OR 0.97, 95% CI 0.27 to 3.50, 8 RCTs, very low-quality evidence), intraoperative complications (OR 0.93, 95% CI 0.34 to 2.55, 8 RCTs, very low-quality evidence), or postoperative complications (OR 0.80, 95% CI 0.21 to 3.13, 8 RCTs, very low-quality evidence) between ligature and all types of mechanical devices. However, our analyses of secondary outcomes revealed that use of mechanical devices saved approximately nine minutes of total operating time when compared with use of a ligature (mean difference (MD) -9.04 minutes, 95% CI -12.97 to -5.11 minutes, 8 RCTs, very low-quality evidence). However, this finding did not translate into a clinically or statistically significant reduction in inpatient hospital stay (MD 0.02 days, 95% CI -0.12 to 0.17 days, 8 RCTs, very low-quality evidence). Available information was insufficient for reliable comparison of total hospital costs and postoperative pain/quality of life between the two approaches. Overall, evidence across all analyses was of very low quality, with substantial potential for confounding factors. Given the limitations of all studies in terms of bias and the low quality of available evidence, a clear conclusion regarding superiority of any one particular type of mechanical device over another is not possible. AUTHORS' CONCLUSIONS: Evidence is insufficient at present to advocate omission of conventional ligature-based appendix stump closure in favour of any single type of mechanical device over another in uncomplicated appendicitis.

Rheumatic Mitral Valve Disease Is Associated With Worse Outcomes in Stroke: A Thailand National Database Study.

BACKGROUND AND PURPOSE: Rheumatic valvular heart disease is associated with the increased risk of cerebrovascular events, although there are limited data on the prognosis of patients with rheumatic mitral valve disease (RMVD) after stroke. METHODS: We examined the association between RMVD and both serious and common cardiovascular and noncardiovascular (respiratory and infective) complications in a cohort of hospitalized stroke patients based in Thailand. Factors associated with in-hospital mortality were also explored. Data were obtained from a National Insurance Database. All hospitalized strokes between October 1, 2004, and January 31, 2013, were included in the current study. Characteristics and outcomes were compared for RMVD and non-RMVD patients. Logistic regression, propensity score matching, and multivariate models were used to assess study outcomes. RESULTS: In total, 594 681 patients (mean [SD] age=64 [14.5] years) with a diagnosis of stroke (ischemic=306 154; hemorrhagic=195 392; undetermined=93 135) were included in this study, of whom 5461 had RMVD. Results from primary analyses showed that after ischemic stroke, and controlling for potential confounding covariates, RMVD was associated (P<0.001) with increased odds for cardiac arrest (odds ratio [95% confidence interval]=2.13 [1.68-2.70]), shock (2.13 [1.64-2.77]), arrhythmias (1.70 [1.21-2.39]), respiratory failure (2.09 [1.87-2.33]), pneumonia (2.00 [1.81-2.20]), and sepsis (1.39 [1.19-1.63]). In hemorrhagic stroke patients, RMVD was associated with increased odds (fully adjusted model) for respiratory failure (1.26 [1.01-1.57]), and in patients with undetermined stroke, RMVD was associated with increased odds (fully adjusted analyses) for shock (3.00 [1.46-6.14]), respiratory failure (2.70 [1.91-3.79]), and pneumonia (2.42 [1.88-3.11]). CONCLUSIONS: RMVD is associated with the development of cardiac arrest, shock, arrhythmias, respiratory failure, pneumonia, and sepsis after acute stroke.

Incidentally Raised Cardiac Troponin I Has a Worse Prognosis in Older Patients Compared to Those with Normal Cardiac Troponin I and Patients with Acute Coronary Syndrome: A Cohort Study.

BACKGROUND: Incidentally elevated cardiac troponin I (cTnI) levels are common in acutely unwell older patients. However, little is known about how this impacts on the prognosis of these patients. OBJECTIVE: We aimed to investigate whether incidentally elevated cTnI levels (group 1) are associated with poorer outcome when compared to age- and sex-matched patients without an elevated cTnI level (group 2), and to patients diagnosed with acute coronary syndrome (group 3). PATIENTS AND METHODS: This prospective, matched cohort study placed patients ≥75 years old who were admitted to a University teaching hospital into groups 1-3, based on the cTnI levels and underlying diagnosis. Outcomes were compared between the groups using mixed-effects regression models and adjusted for renal function and C-reactive protein. All-cause mortality at discharge, at 1 month and 3 months, alongside the length of hospital stay (LOS), were recorded. RESULTS: In total, 315 patients were included, with 105 patients in each of the 3 groups. The mean age was 84.8 ± 5.5 years, with 41.9% males. All patients were followed up for 3 months. The percent all-cause mortality at discharge and the LOS for groups 1, 2 and 3 were 12.4, 3.8 and 8.6% and 11.2, 8.5 and 7.7 days, respectively. Group 1 had significantly increased mortality at 3 months [odds ratio (OR) 2.80, 95% confidence interval (CI) 1.12-6.96; p = 0.040] and LOS (OR 1.39, 95% CI 1.08-1.79; p = 0.008) compared to group 2 and did not differ significantly when compared to 3-month mortality (OR 2.39, 95% CI 0.91-6.29; p = 0.079) or LOS (OR 1.26, 95% CI 0.96-1.66; p = 0.097) in group 3. CONCLUSION: There is a significant association between an incidental rise in cTnI level with mortality and LOS in older patients. Further research is required to evaluate whether a more systematic management of these patients would improve the prognosis.

The clinical utility of Multiplate analyser measurement in platelet function testing following stroke and transient ischaemic attack.

BACKGROUND: Platelet responsiveness to aspirin in people with cerebrovascular disease is poorly understood. OBJECTIVES: To determine: (i) normal reference range, imprecision and reproducibility of the Multiplate instrument in healthy volunteers naive to aspirin; (ii) imprecision and reproducibility of the Multiplate instrument in acute stroke and transient ischaemic attack (TIA); (iii) the relationship between aspirin responsiveness and clinical outcome. MATERIALS AND METHODS: We evaluated platelet function response to three agonists [Adenosine Diphosphate (ADP), Arachidonic Acid (AA), Collagen (Col)] using the Mulitplate platelet function analyser in a two-phase pilot study. In phase 1, we recruited healthy volunteers to determine the normal reference range and imprecision of the Multiplate instrument. In phase 2, we assessed platelet function in acute stroke or TIA patients presenting to hospital. These patients were bled within 24 h of presentation and between 12 and 24 h after ≥75 mg dose of Aspirin. Patients were followed up to 1 yr to assess mortality and recurrent cardiovascular event. RESULTS: Overall, 29 healthy volunteers and 81 stroke/TIA patients were recruited. On assessing components of variance, Multiplate testing is reproducible and precise in volunteers and stroke/TIA patients. In stroke patients receiving aspirin, Bland-Altman plots show initial day 1 measurement provided a reliable measure of continuing response to aspirin at day 3. We defined one-third of patients as aspirin resistant [31.8% (95% CI: 22.1%-42.8%)] using cut off mean aggregation of ≥23.08% for AA and mean aggregation of ≥80.76% for ADP. CONCLUSION: The Multiplate device gives reproducible, precise results in volunteers and stroke/TIA patients.

Evaluating the Predictive Features of Person-Centric Knowledge Graph Embeddings: Unfolding Ablation Studies.

Developing novel predictive models with complex biomedical information is challenging due to various idiosyncrasies related to heterogeneity, standardization or sparseness of the data. We previously introduced a person-centric ontology to organize information about individual patients, and a representation learning framework to extract person-centric knowledge graphs (PKGs) and to train Graph Neural Networks (GNNs). In this paper, we propose a systematic approach to examine the results of GNN models trained with both structured and unstructured information from the MIMIC-III dataset. Through ablation studies on different clinical, demographic, and social data, we show the robustness of this approach in identifying predictive features in PKGs for the task of readmission prediction.

Pragmatic De-Identification of Cross-Domain Unstructured Documents: A Utility-Preserving Approach with Relation Extraction Filtering.

The volume of information, and in particular personal information, generated each day is increasing at a staggering rate. The ability to leverage such information depends greatly on being able to satisfy the many compliance and privacy regulations that are appearing all over the world. We present READI, a utility preserving framework for the unstructured document de-identification. READI leverages Named Entity Recognition and Relation Extraction technology to improve the quality of the entity detection, thus improving the overall quality of the data de-identification process. In this proof of concept study, we evaluate the proposed approach on two different datasets and compare with the existing state-of-the-art approaches. We show that Relation Extraction-based Approach for De-Identification (READI) notably reduces the number of false positives and improves the utility of the de-identified text.

Automated Feature Selection from Medical Literature.

We propose an automated approach to rank the most salient variables related to a certain clinical phenomenon from scientific literature. Our solution is an automated approach to improve the efficiency of the collection of different health-related measures from a population, and to accelerate the discovery of novel associations and dependencies between health-related concepts.

Investigating Cross-Domain Binary Relation Classification in Biomedical Natural Language Processing.

This paper addresses the challenge of binary relation classification in biomedical Natural Language Processing (NLP), focusing on diverse domains including gene-disease associations, compound protein interactions, and social determinants of health (SDOH). We evaluate different approaches, including fine-tuning Bidirectional Encoder Representations from Transformers (BERT) models and generative Large Language Models (LLMs), and examine their performance in zero and few-shot settings. We also introduce a novel dataset of biomedical text annotated with social and clinical entities to facilitate research into relation classification. Our results underscore the continued complexity of this task for both humans and models. BERT-based models trained on domain-specific data excelled in certain domains and achieved comparable performance and generalization power to generative LLMs in others. Despite these encouraging results, these models are still far from achieving human-level performance. We also highlight the significance of high-quality training data and domain-specific fine-tuning on the performance of all the considered models.

Serum Albumin and Post-Stroke Outcomes: Analysis of UK Regional Registry Data, Systematic Review, and Meta-Analysis.

Hypoalbuminemia associates with poor acute ischemic stroke (AIS) outcomes. We hypothesised a non-linear relationship and aimed to systematically assess this association using prospective stroke data from the Norfolk and Norwich Stroke and TIA Register. Consecutive AIS patients aged ≥40 years admitted December 2003-December 2016 were included. Outcomes: In-hospital mortality, poor discharge, functional outcome (modified Rankin score 3-6), prolonged length of stay (PLoS) > 4 days, and long-term mortality. Restricted cubic spline regressions investigated the albumin-outcome relationship. We updated a systematic review (PubMed, Scopus, and Embase databases, January 2020-June 2023) and undertook a meta-analysis. A total of 9979 patients were included; mean age (standard deviation) = 78.3 (11.2) years; mean serum albumin 36.69 g/L (5.38). Compared to the cohort median, albumin < 37 g/L associated with up to two-fold higher long-term mortality (HRmax; 95% CI = 2.01; 1.61-2.49) and in-hospital mortality (RRmax; 95% CI = 1.48; 1.21-1.80). Albumin > 44 g/L associated with up to 12% higher long-term mortality (HRmax1.12; 1.06-1.19). Nine studies met our inclusion criteria totalling 23,597 patients. Low albumin associated with increased risk of long-term mortality (two studies; relative risk 1.57 (95% CI 1.11-2.22; I2 = 81.28)), as did low-normal albumin (RR 1.10 (95% CI 1.01-1.20; I2 = 0.00)). Strong evidence indicates increased long-term mortality in AIS patients with low or low-normal albumin on admission.

Changes in antiplatelet use prior to incident ischaemic stroke over 7 years in a UK centre and the association with stroke subtype.

BACKGROUND: guidelines have changed in relation to the indication of antiplatelet therapy for the primary and secondary prevention of stroke. Of interest is how the proportion of patients who had or had not taken antiplatelet agents prior to an incident stroke has changed over time, whether the type of antiplatelet agents used has altered and whether prior antiplatelet use is associated with a particular ischaemic stroke subtype. METHODS: a stroke register was retrospectively examined. All ischaemic stroke patients admitted between January 2004 and March 2011 to a single University Hospital with a catchment population of ∼750,000 were included. We excluded those who were on anticoagulants prior to the ischaemic stroke. RESULTS: a total of 4,307 ischaemic stroke patients [male 47.5%, mean age 77.6 (SD 11.7) years] were included. Of them, 54.7% (SD 2.2%) were not on any antiplatelet therapy prior to their incident stroke. The type and pattern of antiplatelet use prior to stroke did not change significantly during the 7-year study period, and there were no statistically significant differences between different ischaemic stroke subtypes with regards to prior antiplatelet use. CONCLUSIONS: our findings highlight the requirement to improve currently available risk prediction scores as well as the potential clinical impact of antiplatelet resistance within the at risk population who are already on antiplatelets. These findings also indicate that targeting of multiple risk factors may be very important in stroke prevention.

Automatic Mapping of Terminology Items with Transformers.

Biomedical ontologies are a key component in many systems for the analysis of textual clinical data. They are employed to organize information about a certain domain relying on a hierarchy of different classes. Each class maps a concept to items in a terminology developed by domain experts. These mappings are then leveraged to organize the information extracted by Natural Language Processing (NLP) models to build knowledge graphs for inferences. The creation of these associations, however, requires extensive manual review. In this paper, we present an automated approach and repeatable framework to learn a mapping between ontology classes and terminology terms derived from vocabularies in the Unified Medical Language System (UMLS) metathesaurus. According to our evaluation, the proposed system achieves a performance close to humans and provides a substantial improvement over existing systems developed by the National Library of Medicine to assist researchers through this process.

Subtyping Gastrointestinal Surgical Outcomes from Real World Data: A Comprehensive Analysis of UK Biobank.

Chronic gastrointestinal (GI) conditions, such as inflammatory bowel diseases (IBD), offer a promising opportunity to create classification systems that can enhance the accuracy of predicting the most effective therapies and prognosis for each patient. Here, we present a novel methodology to explore disease subtypes using our open-sourced BiomedSciAI toolkit. Applying methods available in this toolkit on the UK Biobank, including subpopulation-based feature selection and multi-dimensional subset scanning, we aimed to discover unique subgroups from GI surgery cohorts. Of a 12,073-patient cohort, a subgroup of 440 IBD patients was discovered with an increased risk of a subsequent GI surgery (OR: 2.21, 95% CI [1.81-2.69]). We iteratively demonstrate the discovery process using an additional cohort (with a narrower definition of GI surgery). Our results show that the iterative process can refine the subgroup discovery process and generate novel hypotheses to investigate determinants of treatment response.

Predicting 10-year stroke mortality: development and validation of a nomogram.

Predicting long-term stroke mortality is a clinically important and unmet need. We aimed to develop and internally validate a 10-year ischaemic stroke mortality prediction score. In this UK cohort study, 10,366 patients with first-ever ischaemic stroke between January 2003 and December 2016 were followed up for a median (interquartile range) of 5.47 (2.96-9.15) years. A Cox proportional-hazards model was used to predict 10-year post-admission mortality. The predictors associated with 10-year mortality included age, sex, Oxfordshire Community Stroke Project classification, estimated glomerular filtration rate (eGFR), pre-stroke modified Rankin Score, admission haemoglobin, sodium, white blood cell count and comorbidities (atrial fibrillation, coronary heart disease, heart failure, cancer, hypertension, chronic obstructive pulmonary disease, liver disease and peripheral vascular disease). The model was internally validated using bootstrap resampling to assess optimism in discrimination and calibration. A nomogram was created to facilitate application of the score at the point of care. Mean age (SD) was 78.5 ± 10.9 years, 52% female. Most strokes were partial anterior circulation syndromes (38%). 10-year mortality predictors were: total anterior circulation stroke (hazard ratio, 95% confidence intervals) (2.87, 2.62-3.14), eGFR < 15 (1.97, 1.55-2.52), 1-year increment in age (1.04, 1.04-1.05), liver disease (1.50, 1.20-1.87), peripheral vascular disease (1.39, 1.23-1.57), cancers (1.37, 1.27-1.47), heart failure (1.24, 1.15-1.34), 1-point increment in pre-stroke mRS (1.20, 1.17-1.22), atrial fibrillation (1.17, 1.10-1.24), coronary heart disease (1.09, 1.02-1.16), chronic obstructive pulmonary disease (1.13, 1.03-1.25) and hypertension (0.77, 0.72-0.82). Upon internal validation, the optimism-adjusted c-statistic was 0.76 and calibration slope was 0.98. Our 10-year mortality model uses routinely collected point-of-care information. It is the first 10-year mortality score in stroke. While the model was internally validated, further external validation is also warranted.