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1.
JACC Adv ; 3(8): 101064, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39050815

RESUMO

Background: Heart failure with preserved ejection fraction (HFpEF) is the predominant form of HF in older adults. It represents a heterogenous clinical syndrome that is less well understood across different ethnicities. Objectives: This study aimed to compare the clinical presentation and assess the diagnostic performance of existing HFpEF diagnostic tools between ethnic groups. Methods: A validated Natural Language Processing (NLP) algorithm was applied to the electronic health records of a large London hospital to identify patients meeting the European Society of Cardiology criteria for a diagnosis of HFpEF. NLP extracted patient demographics (including self-reported ethnicity and socioeconomic status), comorbidities, investigation results (N-terminal pro-B-type natriuretic peptide, H2FPEF scores, and echocardiogram reports), and mortality. Analyses were stratified by ethnicity and adjusted for socioeconomic status. Results: Our cohort consisted of 1,261 (64%) White, 578 (29%) Black, and 134 (7%) Asian patients meeting the European Society of Cardiology HFpEF diagnostic criteria. Compared to White patients, Black patients were younger at diagnosis and more likely to have metabolic comorbidities (obesity, diabetes, and hypertension) but less likely to have atrial fibrillation (30% vs 13%; P < 0.001). Black patients had lower N-terminal pro-B-type natriuretic peptide levels and a lower frequency of H2FPEF scores ≥6, indicative of likely HFpEF (26% vs 44%; P < 0.0001). Conclusions: Leveraging an NLP-based artificial intelligence approach to quantify health inequities in HFpEF diagnosis, we discovered that established markers systematically underdiagnose HFpEF in Black patients, possibly due to differences in the underlying comorbidity patterns. Clinicians should be aware of these limitations and its implications for treatment and trial recruitment.

2.
Eur J Heart Fail ; 26(2): 302-310, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38152863

RESUMO

AIM: Heart failure with preserved ejection fraction (HFpEF) remains under-diagnosed in clinical practice despite accounting for nearly half of all heart failure (HF) cases. Accurate and timely diagnosis of HFpEF is crucial for proper patient management and treatment. In this study, we explored the potential of natural language processing (NLP) to improve the detection and diagnosis of HFpEF according to the European Society of Cardiology (ESC) diagnostic criteria. METHODS AND RESULTS: In a retrospective cohort study, we used an NLP pipeline applied to the electronic health record (EHR) to identify patients with a clinical diagnosis of HF between 2010 and 2022. We collected demographic, clinical, echocardiographic and outcome data from the EHR. Patients were categorized according to the left ventricular ejection fraction (LVEF). Those with LVEF ≥50% were further categorized based on whether they had a clinician-assigned diagnosis of HFpEF and if not, whether they met the ESC diagnostic criteria. Results were validated in a second, independent centre. We identified 8606 patients with HF. Of 3727 consecutive patients with HF and LVEF ≥50% on echocardiogram, only 8.3% had a clinician-assigned diagnosis of HFpEF, while 75.4% met ESC criteria but did not have a formal diagnosis of HFpEF. Patients with confirmed HFpEF were hospitalized more frequently; however the ESC criteria group had a higher 5-year mortality, despite being less comorbid and experiencing fewer acute cardiovascular events. CONCLUSIONS: This study demonstrates that patients with undiagnosed HFpEF are an at-risk group with high mortality. It is possible to use NLP methods to identify likely HFpEF patients from EHR data who would likely then benefit from expert clinical review and complement the use of diagnostic algorithms.


Assuntos
Insuficiência Cardíaca , Humanos , Volume Sistólico , Função Ventricular Esquerda , Inteligência Artificial , Estudos Retrospectivos , Prognóstico
3.
IEEE Trans Inf Theory ; 66(9): 5904-5926, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32921802

RESUMO

Extracting information from nonlinear measurements is a fundamental challenge in data analysis. In this work, we consider separable inverse problems, where the data are modeled as a linear combination of functions that depend nonlinearly on certain parameters of interest. These parameters may represent neuronal activity in a human brain, frequencies of electromagnetic waves, fluorescent probes in a cell, or magnetic relaxation times of biological tissues. Separable nonlinear inverse problems can be reformulated as underdetermined sparse-recovery problems, and solved using convex programming. This approach has had empirical success in a variety of domains, from geophysics to medical imaging, but lacks a theoretical justification. In particular, compressed-sensing theory does not apply, because the measurement operators are deterministic and violate incoherence conditions such as the restricted-isometry property. Our main contribution is a theory for sparse recovery adapted to deterministic settings. We show that convex programming succeeds in recovering the parameters of interest, as long as their values are sufficiently distinct with respect to the correlation structure of the measurement operator. The theoretical results are illustrated through numerical experiments for two applications: heat-source localization and estimation of brain activity from electroencephalography data.

5.
Dig Dis Sci ; 65(9): 2534-2541, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32036513

RESUMO

INTRODUCTION: There is marked variability in colonoscopy quality, limiting its effectiveness in colorectal cancer prevention. Multiple indicators have been established as markers for colonoscopy quality; however, there are conflicting data on the effects of quality reporting programs on endoscopist performance. In this study, we investigate the impact of a multicenter quarterly report card initiative on colonoscopy quality metric performance. METHODS: Data were collected from 194 endoscopists at 10 participating sites throughout New York City using a Qualified Clinical Data Registry from January 2013 to December 2014. Adenoma detection rate (ADR), cecal intubation rate, withdrawal time, bowel preparation quality and appropriate interval recommendations were tracked. Report cards were distributed to each site on a quarterly basis and technical assistance was provided as needed. Performance trends were analyzed using the Cochran-Armitage trend and analysis of variance tests. RESULTS: 37,258 screening colonoscopies were performed during the study period. There was a positive performance trend for ADR over time from the first quarter of 2013 to the last quarter of 2014 (15.6-25.7%; p < 0.001). There were also increases in cecal intubation rates (78.2-92.6%; p < 0.001), bowel preparation adequacy rates (77.5-92.8%; p < 0.001), and adherence to appropriate screening intervals (28.0-55.0%; p < 0.001). There was no clinically significant change in mean withdrawal time. CONCLUSIONS: The implementation of a quarterly report card initiative resulted in statistically significant improvements in adenoma detection, cecal intubation, bowel preparation adequacy rates, and appropriate recommended screening intervals.


Assuntos
Benchmarking/normas , Colonoscopia/normas , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer/normas , Padrões de Prática Médica/normas , Melhoria de Qualidade/normas , Indicadores de Qualidade em Assistência à Saúde/normas , Competência Clínica/normas , Neoplasias Colorretais/diagnóstico , Feminino , Disparidades em Assistência à Saúde/normas , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque , Sistema de Registros
6.
Rheumatology (Oxford) ; 59(3): 524-533, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31377781

RESUMO

OBJECTIVE: Damage in patients with systemic lupus erythematosus is irreversible change in organs due to disease activity, concomitant disease or medication side-effects. It is measured using the Systemic Lupus International Collaborative Clinics Damage Index (SDI) and is associated with increased mortality. Previous reports have suggested associations between damage accrual and various ethnic, disease and treatment factors, but there is a dearth of long-term follow-up data from large multi-ethnic cohorts. We describe a study of damage and mortality in 300 patients from London, UK followed for up to 40 years. METHODS: We carried out retrospective analysis of medical records and SDI scores of 300 patients followed for up to 40 years (median 13.3 years). Characteristics of the groups who did and did not develop damage and those who died or survived to the end of follow-up were compared using univariable and multivariable analysis. Kaplan-Meier analysis was used to analyse factors affecting mortality and accrual of damage. RESULTS: Damage developed in 231/300 (77%) of patients. There was a linear accrual of damage over 40 years follow-up. Factors associated with damage were African/Caribbean ethnicity, renal and cerebral involvement, early use of high-dose corticosteroids or immunosuppressants, anti-RNP and antiphospholipid antibodies. Damage was strongly associated with mortality. Of 87 patients who died, 93% had damage compared with 70% of survivors (P < 0.001). CONCLUSION: Development of damage is strongly associated with increased mortality. We identified groups at increased risk of developing damage, including those treated with high-dose steroids and immunosuppressants within the first two years.


Assuntos
Lúpus Eritematoso Sistêmico/patologia , Corticosteroides/uso terapêutico , Adulto , Progressão da Doença , Feminino , Seguimentos , Humanos , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Taxa de Sobrevida , Reino Unido/epidemiologia
9.
Ther Adv Urol ; 10(8): 235-242, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30034542

RESUMO

Since prehistoric times, our understanding of urology has rapidly expanded. Whilst primitive urologists began by using urine as a therapeutic substance, modern urologists may find themselves removing a kidney remotely by driving a robotic arm, with seven degrees of movement, while using image overlay-augmented reality. This review provides an insight into the potential status of urological technology in 20 years' time, assessed through an analysis of developments in imaging, diagnostics, robotics and further technologies. A particular emphasis is given to the promising fields of minimally invasive techniques, nanotechnology and tissue engineering, which likely hold the key to a new era for urology.

10.
Inverse Probl ; 34(9)2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30880863

RESUMO

Magnetic resonance fingerprinting (MRF) is a technique for quantitative estimation of spin- relaxation parameters from magnetic-resonance data. Most current MRF approaches assume that only one tissue is present in each voxel, which neglects intravoxel structure, and may lead to artifacts in the recovered parameter maps at boundaries between tissues. In this work, we propose a multicompartment MRF model that accounts for the presence of multiple tissues per voxel. The model is fit to the data by iteratively solving a sparse linear inverse problem at each voxel, in order to express the measured magnetization signal as a linear combination of a few elements in a precomputed fingerprint dictionary. Thresholding-based methods commonly used for sparse recovery and compressed sensing do not perform well in this setting due to the high local coherence of the dictionary. Instead, we solve this challenging sparse-recovery problem by applying reweighted-𝓁1-norm regularization, implemented using an efficient interior-point method. The proposed approach is validated with simulated data at different noise levels and undersampling factors, as well as with a controlled phantom-imaging experiment on a clinical magnetic-resonance system.

11.
J Surg Case Rep ; 2017(12): rjx245, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29250315

RESUMO

A 91-year-old female presented to the Emergency Department with a 10-day history of constipation and abdominal pain. Abdominal examination was normal and rectal examination showed faecal loading. A phosphate enema was given and the patient was admitted. Overnight, the patient's GCS dropped from 15/15 to 3/15 and an arterial blood gas showed a lactate of 8 mmol/L (1.5 on admission). Abdomen remained soft throughout. A CT scan showed a large amount of free air and free fluid within the abdomen and pelvis, highly suspicious for perforation. Hepatic portal venous gas (HPVG) was visible, with portal venous air fluid levels noted. The patient was treated palliatively and died shortly thereafter. HPVG is a recognized but rarely identified radiological sign, which is a poor prognostic indicator, with most cases subsequently proving terminal, often due to subsequent bowel necrosis.

13.
Gastroenterology ; 150(4): 1009-18, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26907603
14.
Cardiol Young ; 26(1): 161-3, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25599745

RESUMO

Prolongation of the QT interval and development of torsades de pointes are known in patients with complete heart block and profound bradycardia. We report the case of a patient with complete heart block and torsades, with long QT seen during a period of junctional tachycardia at a rate faster than the minimum pacemaker rate.


Assuntos
Bloqueio Cardíaco/complicações , Síndrome do QT Longo/etiologia , Marca-Passo Artificial , Torsades de Pointes/etiologia , Adolescente , Humanos , Masculino
15.
PLoS One ; 10(8): e0136115, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26287800

RESUMO

The effects of endogenous and synthetic glucocorticoids on fetal lung maturation are well-established, although the role of leptin in lung development before birth is unclear. This study examined mRNA and protein levels of the signalling long-form leptin receptor (Ob-Rb) in fetal ovine lungs towards term, and after experimental manipulation of glucocorticoid levels in utero by fetal cortisol infusion or maternal dexamethasone treatment. In fetal ovine lungs, Ob-Rb protein was localised to bronchiolar epithelium, bronchial cartilage, vascular endothelium, alveolar macrophages and type II pneumocytes. Pulmonary Ob-Rb mRNA abundance increased between 100 (0.69 fractional gestational age) and 144 days (0.99) of gestation, and by 2-4-fold in response to fetal cortisol infusion and maternal dexamethasone treatment. In contrast, pulmonary Ob-Rb protein levels decreased near term and were halved by glucocorticoid treatment, without any significant change in phosphorylated signal transducer and activator of transcription-3 (pSTAT3) at Ser727, total STAT3 or the pulmonary pSTAT3:STAT3 ratio. Leptin mRNA was undetectable in fetal ovine lungs at the gestational ages studied. These findings demonstrate differential control of pulmonary Ob-Rb transcript abundance and protein translation, and/or post-translational processing, by glucocorticoids in utero. Localisation of Ob-Rb in the fetal ovine lungs, including alveolar type II pneumocytes, suggests a role for leptin signalling in the control of lung growth and maturation before birth.


Assuntos
Pulmão/embriologia , Pulmão/metabolismo , Receptores para Leptina/genética , Receptores para Leptina/metabolismo , Células Epiteliais Alveolares/metabolismo , Animais , Dexametasona/farmacologia , Feminino , Feto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Glucocorticoides/farmacologia , Hidrocortisona/sangue , Hidrocortisona/farmacologia , Pulmão/efeitos dos fármacos , Fosforilação , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição STAT3/química , Fator de Transcrição STAT3/metabolismo , Carneiro Doméstico , Transdução de Sinais
16.
World J Gastroenterol ; 18(32): 4350-6, 2012 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-22969198

RESUMO

AIM: To examine effects of chronic methadone usage on bowel visualization, preparation, and repeat colonoscopy. METHODS: In-patient colonoscopy reports from October, 2004 to May, 2009 for methadone dependent (MD) patients were retrospectively evaluated and compared to matched opioid naive controls (C). Strict criteria were applied to exclude patients with risk factors known to cause constipation or gastric dysmotility. Colonoscopy reports of all eligible patients were analyzed for degree of bowel visualization, assessment of bowel preparation (good, fair, or poor), and whether a repeat colonoscopy was required. Bowel visualization was scored on a 4 point scale based on multiple prior studies: excellent = 1, good = 2, fair = 3, or poor = 4. Analysis of variance (ANOVA) and Pearson χ(2) test were used for data analyses. Subgroup analysis included correlation between methadone dose and colonoscopy outcomes. All variables significantly differing between MD and C groups were included in both univariate and multivariate logistic regression analyses. P values were two sided, and < 0.05 were considered statistically significant. RESULTS: After applying exclusionary criteria, a total of 178 MD patients and 115 C patients underwent a colonoscopy during the designated study period. A total of 67 colonoscopy reports for MD patients and 72 for C were included for data analysis. Age and gender matched controls were randomly selected from this population to serve as controls in a numerically comparable group. The average age for MD patients was 52.2 ± 9.2 years (range: 32-72 years) years compared to 54.6 ± 15.5 years (range: 20-81 years) for C (P = 0.27). Sixty nine percent of patients in MD and 65% in C group were males (P = 0.67). When evaluating colonoscopy reports for bowel visualization, MD patients had significantly greater percentage of solid stool (i.e., poor visualization) compared to C (40.3% vs 6.9%, P < 0.001). Poor bowel preparation (35.8% vs 9.7%, P < 0.001) and need for repeat colonoscopy (32.8% vs 12.5%, P = 0.004) were significantly higher in MD group compared to C, respectively. Under univariate analysis, factors significantly associated with MD group were presence of fecal particulate [odds ratio (OR), 3.89, 95% CI: 1.33-11.36, P = 0.01] and solid stool (OR, 13.5, 95% CI: 4.21-43.31, P < 0.001). Fair (OR, 3.82, 95% CI: 1.63-8.96, P = 0.002) and poor (OR, 8.10, 95% CI: 3.05-21.56, P < 0.001) assessment of bowel preparation were more likely to be associated with MD patients. Requirement for repeat colonoscopy was also significant higher in MD group (OR, 3.42, 95% CI: 1.44-8.13, P = 0.01). In the multivariate analyses, the only variable independently associated with MD group was presence of solid stool (OR, 7.77, 95% CI: 1.66-36.47, P = 0.01). Subgroup analysis demonstrated a general trend towards poorer bowel visualization with higher methadone dosage. ANOVA analysis demonstrated that mean methadone dose associated with presence of solid stool (poor visualization) was significantly higher compared to mean dosage for clean colon (excellent visualization, P = 0.02) or for those with liquid stool only (good visualization, P = 0.01). CONCLUSION: Methadone dependence is a risk factor for poor bowel visualization and leads to more repeat colonoscopies. More aggressive bowel preparation may be needed in MD patients.


Assuntos
Catárticos , Colonoscopia , Metadona , Entorpecentes , Transtornos Relacionados ao Uso de Substâncias , Falha de Tratamento , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Estudos de Casos e Controles , Estudos de Coortes , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
World J Gastroenterol ; 16(3): 345-7, 2010 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-20082480

RESUMO

AIM: To re-evaluate the theory that colonic diverticulosis is associated with relapse of Clostridium difficile associated disease (CDAD) in light of data suggesting increasing rates of CDAD infection and relapse. METHODS: Charts were reviewed for patients with recurrent CDAD who had also had a prior colonoscopy or flexible sigmoidoscopy. An age and gender matched control group was used to compare the prevalence of diverticulosis. RESULTS: Twenty-two patients met the study criteria, and the prevalence of diverticulosis in patients with CDAD relapse was 23% compared to 32% in age and sex matched controls (P = 0.44). A significant proportion of patients with CDAD relapse had co-morbidities associated with immune suppression. CONCLUSION: Diverticulosis does not appear to be associated with CDAD relapse.


Assuntos
Clostridioides difficile , Diverticulose Cólica/epidemiologia , Enterocolite Pseudomembranosa/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Recidiva , Estudos Retrospectivos , Fatores de Risco
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