Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 105
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Clin Gastroenterol Hepatol ; 21(10): 2570-2577.e1, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36813013

RESUMO

BACKGROUND & AIMS: The MRI-AST (MAST) score accurately identifies patients with at-risk nonalcoholic steatohepatitis, defined as nonalcoholic steatohepatitis with nonalcoholic fatty liver disease activity score ≥4 and fibrosis stage ≥2 at highest risk for disease progression. It is important to determine the robustness of the MAST score in predicting major adverse liver outcomes (MALO), hepatocellular carcinoma (HCC), liver transplant, and death. METHODS: This retrospective analysis included patients with nonalcoholic fatty liver disease from a tertiary care center who underwent magnetic resonance imaging proton density fat fraction, magnetic resonance elastography, and laboratory testing within 6 months from 2013 to 2022. Other causes of chronic liver disease were excluded. Hazard ratios between logit MAST and MALO (ascites, hepatic encephalopathy, or bleeding esophageal varices), liver transplant, HCC, or liver-related death were computed using a Cox proportional hazards regression model. We computed the hazard ratio of MALO or death associated with MAST scores 0.165-0.242 and 0.242-1.000, using MAST scores 0.000-0.165 as the reference group. RESULTS: Among 346 total patients, average age was 58.8 years with 52.9% females and 34.4% with type 2 diabetes. Average alanine aminotransferase was 50.7 IU/L (24.3-60.0 IU/L), aspartate aminotransferase was 38.05 IU/L (22.00-41.00 IU/L), platelets were 242.9 × 109/L (193.8-290.0 × 109/L), proton density fat fraction was 12.90% (5.90%-18.22%), and liver stiffness on magnetic resonance elastography was 2.75 kPa (2.07-2.90 kPa). Median follow-up was 29.5 months. Fourteen had adverse outcomes, including 10 MALO, 1 HCC, 1 liver transplant, and 2 liver-related deaths. The Cox regression of MAST versus adverse event rate had a hazard ratio of 2.01 (95% confidence interval, 1.59-2.54; P < .0001) for each 1 logit unit increases in MAST. The corresponding Harrell concordance statistic (C statistic) was 0.919 (95% confidence interval, 0.865-0.953). The MAST score ranges of 0.165-0.242 and 0.242-1.0, respectively, had adverse event rate hazard ratio of 7.75 (1.40-42.9; P = .0189) and 22.11 (6.59-74.2; P < .0000) relative to MAST 0-0.165. CONCLUSIONS: The MAST score noninvasively identifies at-risk nonalcoholic steatohepatitis and accurately predicts MALO, HCC, liver transplant, and liver-related death.


Assuntos
Carcinoma Hepatocelular , Diabetes Mellitus Tipo 2 , Neoplasias Hepáticas , Transplante de Fígado , Hepatopatia Gordurosa não Alcoólica , Feminino , Humanos , Pessoa de Meia-Idade , Masculino , Carcinoma Hepatocelular/patologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologia , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Diabetes Mellitus Tipo 2/complicações , Prótons , Neoplasias Hepáticas/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Imageamento por Ressonância Magnética/métodos
2.
Am J Physiol Heart Circ Physiol ; 324(6): H821-H832, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37057991

RESUMO

Electronic cigarettes are often used for smoking cessation as a harm reduction strategy, but studies comparing risks of electronic cigarettes (ECs) and tobacco cigarettes (TCs) are scarce. Ventricular repolarization in people who smoke TCs is abnormal. Baseline repolarization was compared among nonusers (people who do not use TCs or ECs) and people who use ECs or TCs. The acute effects of ECs and TCs on metrics of ventricular repolarization were then compared in people who chronically smoke. A total of 110 participants (59 female), including 35 people (21 females) in the TC cohort, 34 people (17 females) in the EC cohort, and 41 people (21 females) in the nonuser cohort, were included. None of the primary outcomes, Tpeak-end (Tp-e), Tp-e/QT, and Tp-e/QTc, were different among the three cohorts at supine baseline, even when adjusted for sex. When compared with the control exposure standing after acutely using the EC but not the TC, significantly prolonged all three primary indices of ventricular repolarization in people who smoke TCs. The major new finding in this study is that in people who smoke TCs, using an EC compared with a TC significantly prolongs ventricular repolarization. Furthermore, in our subgroup analysis by sex, this adverse effect on repolarization is found only in male, not female, smokers. In summary, chronic TC smoking is the most prevalent, modifiable risk factor for cardiovascular death, including sudden cardiac death. If used for smoking cessation, ECs should only be used in the short term since they too carry their own risks; this risk appears to be greatest in males compared with females who smoke.NEW & NOTEWORTHY The major new finding in this study is that in people who smoke tobacco cigarettes, using an electronic cigarette but not a tobacco cigarette acutely and significantly prolongs several metrics of ventricular repolarization, including Tpeak-Tend, Tpeak-Tend/QT, and Tpeak-Tend/QTc. Furthermore, in our subgroup analysis by sex, this adverse effect on repolarization is found only in male, not female, smokers.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Feminino , Humanos , Masculino , Nicotina/efeitos adversos , Redução do Dano , Fumar/efeitos adversos
4.
Stroke ; 53(8): 2426-2434, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35545939

RESUMO

BACKGROUND: To emphasize treatment speed for time-sensitive conditions, emergency medicine has developed not only the concept of the golden hour, but also the platinum half-hour. Patients with acute stroke treated within the first half-hour of onset have not been previously characterized. METHODS: In this cohort study, we analyzed patients enrolled in the FAST-MAG (Field Administration of Stroke Therapy-Magnesium) trial, testing paramedic prehospital start of neuroprotective agent ≤2 hours of onset. The features of all acute cerebral ischemia, and intracranial hemorrhage patients with treatment starting at ≤30 m of last known well were compared with later-treated patients. RESULTS: Among 1680 patients, 203 (12.1%) received study agents within 30 minutes of last known well. Among platinum half-hour patients, median onset-to-treatment time was 28 minutes (interquartile range, 25-30), and final diagnoses were acute cerebral ischemia in 71.8% (ischemic stroke, 61.5%, TIA 10.3%); intracranial hemorrhage in 26.1%; and mimic in 2.5%. Clinical features among platinum half-hour patients were largely similar to later-treated patients and included age 69 (interquartile range, 57-79), 44.8% women, prehospital Los Angeles Motor Scale median 4 (3-5), and early-postarrival National Institutes of Health Stroke Scale deficit 8 (interquartile range, 3-18). Platinum half-hour acute cerebral ischemia patients did have more severe prehospital motor deficits and younger age; platinum half-hour intracranial hemorrhage patients had more severe motor deficits, were more often female, and less often of Hispanic ethnicity. Outcomes at 3 m in platinum half-hour patients were comparable to later-treated patients and included freedom-from-disability (modified Rankin Scale score, 0-1) in 35.5%, functional independence (modified Rankin Scale score, 0-2) in 53.2%, and mortality in 17.7%. CONCLUSIONS: Prehospital initiation permits treatment start within the platinum half-hour after last known well in a substantial proportion of acute ischemic and hemorrhagic stroke patients, accounting for more than 1 in 10 enrolled in a multicenter trial. Hyperacute platinum half-hour patients were largely similar to later-treated patients and are an attainable target for treatment in prehospital stroke trials.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Doença Aguda , Idoso , Isquemia Encefálica/terapia , Estudos de Coortes , Feminino , Humanos , Hemorragias Intracranianas/terapia , Masculino , Platina/uso terapêutico , Acidente Vascular Cerebral/terapia , Trombectomia , Resultado do Tratamento
5.
J Hepatol ; 76(4): 781-787, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34798176

RESUMO

BACKGROUND & AIMS: Among the large population of patients with non-alcoholic fatty liver disease (NAFLD), identifying those with fibrotic non-alcoholic steatohepatitis (Fibro-NASH) is a clinical priority, as these patients are at the highest risk of disease progression and will benefit most from pharmacologic treatment. MRI-based proton density fat fraction (MRI-PDFF) and MR elastography (MRE) can risk-stratify patients with NAFLD by assessing steatosis and fibrosis, respectively. We developed a highly specific MRI-based score to identify patients with Fibro-NASH. METHODS: This analysis included derivation (n = 103) and validation (n = 244) cohorts of patients who underwent MRI, liver biopsy, transient elastography, and laboratory testing for NAFLD from 2016-2020 in 2 tertiary care centers. To identify Fibro-NASH, a formula was developed based on MRI-PDFF, MRE, and a third variable with highest balanced accuracy per logistic regression. The MRI-aspartate aminotransferase (MAST) score was created and compared to NAFLD fibrosis (NFS), Fibrosis-4 (FIB-4), and FibroScan-aspartate aminotransferase (FAST) scores. RESULTS: The MAST score demonstrated high performance and discrimination in the validation cohort (AUC 0.93; 95% CI 0.88-0.97). In the validation cohorts, the 90% specificity cut-off of 0.242 corresponded to a sensitivity of 75.0%, positive predictive value (PPV) of 50.0% and negative predictive value (NPV) of 96.5%, whereas the 90% sensitivity cut-off of 0.165 corresponded to a specificity of 72.2%, PPV of 29.4%, and NPV of 98.1%. Compared to NFS and FIB-4, MAST resulted in fewer patients having indeterminate scores and an overall higher AUC. Compared to FAST, MAST exhibited a higher AUC and overall better discrimination. CONCLUSION: The MAST score is an accurate, MRI-serum-based score that outperforms previous scores in non-invasively identifying patients at higher risk of Fibro-NASH. LAY SUMMARY: Identifying patients with non-alcoholic steatohepatitis and significant fibrosis - who need treatment and are at risk of clinical liver-related outcomes - is a clinical priority. We developed a more accurate score using MRI-based technologies and a laboratory blood test (aspartate aminotransferase) that outperforms previous non-invasive scores for the identification of patients at higher risk of liver disease progression.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Aspartato Aminotransferases , Biópsia , Progressão da Doença , Fibrose , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/etiologia , Imageamento por Ressonância Magnética/métodos , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia
6.
Ann Noninvasive Electrocardiol ; 27(4): e12958, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35712805

RESUMO

BACKGROUND: The Tpeak-end(Tp-e) has not been compared in all 12 ECG leads in healthy adults to determine if the Tp-e varies across leads. If there is variation, it remains uncertain, which lead(s) are preferred for recording in order to capture the maximal Tp-e value. OBJECTIVE: The purpose of the current study was to determine the optimal leads, if any, to capture the maximal Tp-e interval in healthy young adults. METHODS: In 88 healthy adults (ages 21-38 years), including derivation (n = 21), validation (n = 20), and smoker/vaper (n = 47) cohorts, the Tp-e was measured using commercial computer software (LabChart Pro 8 with ECG module, ADInstruments) in all 12 leads at rest and following a provocative maneuver, abrupt standing. Tp-e was compared to determine which lead(s) most frequently captured the maximal Tp-e interval. RESULTS: In the rest and abrupt standing positions, the Tp-e was not uniform among the 12 leads; the maximal Tp-e was most frequently captured in the precordial leads. At rest, grouping leads V2-V4 resulted in detection of the maximum Tp-e in 85.7% of participants (CI 70.7, 99.9%) versus all other leads (p < .001). Upon abrupt standing, grouping leads V2-V6 together, resulted in detection of the maximum Tp-e 85.0% of participants (CI 69.4, 99.9% versus all other leads; p < .001). These findings were confirmed in the validation cohort, and extended to the smoking/vaping cohort. CONCLUSION: If only a subset of ECG leads will be recorded or analyzed for the Tp-e interval, selection of the precordial leads is preferred since these leads are most likely to capture the maximal Tp-e value.


Assuntos
Eletrocardiografia , Adulto , Estudos de Coortes , Eletrocardiografia/métodos , Humanos , Adulto Jovem
7.
Arthroscopy ; 38(2): 632-642, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34547404

RESUMO

Rigorous and reproducible methodology of controlling for bias is essential for high-quality, evidence-based studies. Propensity score matching (PSM) is a valuable way to control for bias and achieve pseudo-randomization in retrospective observation studies. The purpose of this review is to 1) provide a clear conceptual framework for PSM, 2) recommend how to best report its use in studies, and 3) offer some practical examples of implementation. First, this article covers the concepts behind PSM, discusses its pros and cons, and compares it with other methods of controlling for bias, namely, hard/exact matching and regression analysis. Second, recommendations are given for what to report in a manuscript when PSM is used. Finally, a worked example is provided, which can also serve as a template for the reader's own studies. A study's conclusions are only as strong as its methods. PSM is an invaluable tool for producing rigorous and reproducible results in observational studies. The goal of this article is to give practicing clinical physicians not only a better understanding of PSM and its implications but the ability to implement it for their own studies. STUDY DESIGN: Review.


Assuntos
Pesquisa Biomédica , Viés , Humanos , Pontuação de Propensão , Estudos Retrospectivos
8.
Stroke ; 52(7): 2241-2249, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34011171

RESUMO

Background and Purpose: Clot fragmentation and distal embolization during endovascular thrombectomy for acute ischemic stroke may produce emboli downstream of the target occlusion or in previously uninvolved territories. Susceptibility-weighted magnetic resonance imaging can identify both emboli to distal territories (EDT) and new territories (ENT) as new susceptibility vessel signs (SVS). Diffusion-weighted imaging (DWI) can identify infarcts in new territories (INT). Methods: We studied consecutive acute ischemic stroke patients undergoing magnetic resonance imaging before and after thrombectomy. Frequency, predictors, and outcomes of EDT and ENT detected on gradient-recalled echo imaging (EDT-SVS and ENT-SVS) and INT detected on DWI (INT-DWI) were analyzed. Results: Among 50 thrombectomy-treated acute ischemic stroke patients meeting study criteria, mean age was 70 (±16) years, 44% were women, and presenting National Institutes of Health Stroke Scale score 15 (interquartile range, 8­19). Overall, 21 of 50 (42%) patients showed periprocedural embolic events, including 10 of 50 (20%) with new EDT-SVS, 10 of 50 (20%) with INT-DWI, and 1 of 50 (2%) with both. No patient showed ENT-SVS. On multivariate analysis, model-selected predictors of EDT-SVS were lower initial diastolic blood pressure (odds ratio, 1.09 [95% CI, 1.02­1.16]), alteplase pretreatment (odds ratio, 5.54 [95% CI, 0.94­32.49]), and atrial fibrillation (odds ratio, 7.38 [95% CI, 1.02­53.32]). Classification tree analysis identified pretreatment target occlusion SVS as an additional predictor. On univariate analysis, INT-DWI was less common with internal carotid artery (5%), intermediate with middle cerebral artery (25%), and highest with vertebrobasilar (57%) target occlusions (P=0.02). EDT-SVS was not associated with imaging/functional outcomes, but INT-DWI was associated with reduced radiological hemorrhagic transformation (0% versus 54%; P<0.01). Conclusions: Among acute ischemic stroke patients treated with thrombectomy, imaging evidence of distal emboli, including EDT-SVS beyond the target occlusion and INT-DWI in novel territories, occur in about 2 in every 5 cases. Predictors of EDT-SVS are pretreatment intravenous fibrinolysis, potentially disrupting thrombus structural integrity; atrial fibrillation, possibly reflecting larger target thrombus burden; lower diastolic blood pressure, suggestive of impaired embolic washout; and pretreatment target occlusion SVS sign, indicating erythrocyte-rich, friable target thrombus.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Embolia Intracraniana/diagnóstico por imagem , AVC Isquêmico/diagnóstico por imagem , Imageamento por Ressonância Magnética/tendências , Complicações Cognitivas Pós-Operatórias/diagnóstico por imagem , Trombectomia/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/cirurgia , Feminino , Humanos , Embolia Intracraniana/etiologia , AVC Isquêmico/cirurgia , Masculino , Pessoa de Meia-Idade , Complicações Cognitivas Pós-Operatórias/etiologia , Estudos Prospectivos , Sistema de Registros , Trombectomia/tendências , Fatores de Tempo , Resultado do Tratamento
9.
Clin Gastroenterol Hepatol ; 19(11): 2315-2323.e2, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32828873

RESUMO

BACKGROUND AND AIMS: No prior randomized controlled trial (RCT) has reported patient outcomes of large over-the-scope clip (OTSC) compared to standard hemostasis as initial endoscopic treatment of severe NVUGIB. This was our study aim. METHODS: Patients with bleeding ulcers or Dieulafoy's lesions and major stigmata of hemorrhage - SRH (active spurting bleeding, visible vessel, or clot) - or lesser SRH (oozing bleeding or flat spots - with arterial blood flow by Doppler probe) were randomized to OTSC or standard endoscopic hemostasis (with hemoclips or multipolar electrocoagulation - MPEC). Patients and their healthcare providers were blinded to treatments and made all post-randomization management decisions. Ulcer patients received high dose intravenous infusions of proton pump inhibitors (PPI) for 3 days, then 27 days of oral PPI. 30 day outcomes were prospectively recorded; data management was with SAS; and data analysis was by a statistician. RESULTS: 53 patients (25 OTSC, 28 Standard) were randomized, with similar baseline risk factors. However, there were significant differences in OTSC vs. Standard groups in rates of rebleeding (4% vs. 28.6%; p = .017; relative risk 0.10, 95% confidence intervals 0.01, 0.91; number needed to treat 4); severe complications (0 % vs. 14.3%); and post-randomization units of red cell transfusions (0.04 vs. 0.68). All rebleeds occurred in patients with major SRH and none with lesser SRH. CONCLUSION: 1. OTSC significantly reduced rates of rebleeding, severe complications, and post-randomization red cell transfusions. 2. Patients with major stigmata benefited significantly from hemostasis with OTSC, but those with lesser stigmata did not. (ClinicalTrials.gov, Number: NCT03065465).


Assuntos
Hemostase Endoscópica , Hemorragia Gastrointestinal/terapia , Humanos , Inibidores da Bomba de Prótons , Instrumentos Cirúrgicos , Resultado do Tratamento
10.
J Card Fail ; 27(12): 1321-1327, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34153460

RESUMO

BACKGROUND: Current guidelines recommend measuring natriuretic peptide biomarkers to establish prognosis in patients with chronic heart failure with reduced ejection fraction (HFrEF). We assessed whether a combination biomarkers approach improve prognostication in patients with stable HFrEF. METHODS AND RESULTS: An observational cohort study recruited 202 patients with stable HFrEF at a single center, tertiary care hospital undergoing elective cardiac resynchronization therapy device placement from 2013 to 2015. Twenty-four biomarkers were analyzed individually and in combination using Cox proportion hazard regression model for major adverse cardiac events (ie, death, cardiac transplant, left ventricular assist device placement), and major adverse cardiac events plus HF hospitalizations. The single best biomarker for predicting major adverse cardiac events is peripheral mid-regional pro-adrenomedullin (C statistic = 0.771 ± 0.045) compared to current guideline recommended N-terminal pro b-type natriuretic peptide (C=0.668 ± 0.046). The best combined biomarkers for predicting major adverse cardiac events are blood urea nitrogen, coronary sinus C-reactive protein, peripheral mid-regional pro-atrial natriuretic peptide and peripheral soluble IL-1 receptor-like 1 (C = 0.767 ± 0.036). CONCLUSIONS: In this observational cohort, the combined biomarkers (blood urea nitrogen, C-reactive protein, mid-regional pro-atrial natriuretic peptide and soluble IL-1 receptor-like 1) or the single biomarker (mid-regional pro-adrenomedullin) was superior to N-terminal pro B-type natriuretic peptide, the current guideline recommended biomarker in predicting cardiovascular outcomes in patients with HFrEF. Larger studies are needed to validate these findings and examine whether single or combined biomarkers improve HFrEF prognostication.


Assuntos
Insuficiência Cardíaca , Biomarcadores , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Humanos , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Prognóstico , Medição de Risco , Volume Sistólico
11.
Am J Obstet Gynecol ; 224(2): 215.e1-215.e7, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32739399

RESUMO

BACKGROUND: Aberrant fetal programming in gestational diabetes mellitus seems to increase the risk of obesity, type 2 diabetes, and cardiovascular disease. The inability to accurately identify gestational diabetes mellitus in the first trimester of pregnancy has thwarted ascertaining whether early therapeutic interventions reduce the predisposition to these prevalent medical disorders. OBJECTIVE: A metabolomics study was conducted to determine whether advanced analytical methods could identify accurate predictors of gestational diabetes mellitus in early pregnancy. STUDY DESIGN: This nested observational case-control study was composed of 92 gravidas (46 in the gestational diabetes mellitus group and 46 in the control group) in early pregnancy, who were matched by maternal age, body mass index, and gestational age at urine collection. Gestational diabetes mellitus was diagnosed according to community standards. A comprehensive metabolomics platform measured 626 endogenous metabolites in randomly collected urine. Consensus multivariate criteria or the most important by 1 method identified low-molecular weight metabolites independently associated with gestational diabetes mellitus, and a classification tree selected a subset most predictive of gestational diabetes mellitus. RESULTS: Urine for both groups was collected at a mean gestational age of 12 weeks (range, 6-19 weeks' gestation). Consensus multivariate analysis identified 11 metabolites independently linked to gestational diabetes mellitus. Classification tree analysis selected a 7-metabolite subset that predicted gestational diabetes mellitus with an accuracy of 96.7%, independent of maternal age, body mass index, and time of urine collection. CONCLUSION: Validation of this high-accuracy model by a larger study is now needed to support future studies to determine whether therapeutic interventions in the first trimester of pregnancy for gestational diabetes mellitus reduce short- and long-term morbidity.


Assuntos
Diabetes Gestacional/urina , Idade Gestacional , Metabolômica , Adulto , Alanina/análogos & derivados , Alanina/urina , Arginina/análogos & derivados , Arginina/urina , Carnitina/análogos & derivados , Carnitina/urina , Estudos de Casos e Controles , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/terapia , Dietoterapia , Dopamina/urina , Diagnóstico Precoce , Epigênese Genética , Feminino , Desenvolvimento Fetal/genética , Teste de Tolerância a Glucose , Glucuronídeos/urina , Humanos , Hipoglicemiantes/uso terapêutico , Lactonas/urina , Lisina/análogos & derivados , Lisina/urina , Meglutol/análogos & derivados , Meglutol/urina , Neopterina/análogos & derivados , Neopterina/urina , Ácido Orótico/análogos & derivados , Ácido Orótico/urina , Fenóis/urina , Gravidez , Ribonucleosídeos/urina , Sulfetos/urina
12.
Am J Physiol Heart Circ Physiol ; 319(3): H547-H556, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32734819

RESUMO

Tobacco cigarette (TC) smoking has never been lower in the United States, but electronic cigarette (EC) vaping has reached epidemic proportions among our youth. Endothelial dysfunction, as measured by flow-mediated vasodilation (FMD) is a predictor of future atherosclerosis and adverse cardiovascular events and is impaired in young TC smokers, but whether FMD is also reduced in young EC vapers is uncertain. The aim of this study in otherwise healthy young people was to compare the effects of acute and chronic tobacco cigarette (TC) smoking and electronic cigarette (EC) vaping on FMD. FMD was compared in 47 nonsmokers (NS), 49 chronic EC vapers, and 40 chronic TC smokers at baseline and then after EC vapers (n = 31) and nonsmokers (n = 47) acutely used an EC with nicotine (ECN), EC without nicotine (EC0), and nicotine inhaler (NI) at ~4-wk intervals and after TC smokers (n = 33) acutely smoked a TC, compared with sham control. Mean age (NS, 26.3 ± 5.2 vs. EC, 27.4 ± 5.45 vs. TC, 27.1 ± 5.51 yr, P = 0.53) was similar among the groups, but there were more female nonsmokers. Baseline FMD was not different among the groups (NS, 7.7 ± 4.5 vs. EC:6.6 ± 3.6 vs. TC, 7.9 ± 3.7%∆, P = 0.35), even when compared by group and sex. Acute TC smoking versus control impaired FMD (FMD pre-/postsmoking, -2.52 ± 0.92 vs. 0.65 ± 0.93%∆, P = 0.02). Although the increase in plasma nicotine was similar after EC vapers used the ECN versus TC smokers smoked the TC (5.75 ± 0.74 vs. 5.88 ± 0.69 ng/mL, P = 0.47), acute EC vaping did not impair FMD. In otherwise healthy young people who regularly smoke TCs or ECs, impaired FMD compared with that in nonsmokers was not present at baseline. However, FMD was significantly impaired after smoking one TC, but not after vaping an equivalent "dose" (estimated by change in plasma nicotine) of an EC, consistent with the notion that non-nicotine constituents in TC smoke mediate the impairment. Although it is reassuring that acute EC vaping did not acutely impair FMD, it would be dangerous and premature to conclude that ECs do not lead to atherosclerosis.NEW & NOTEWORTHY In our study of otherwise healthy young people, baseline flow-mediated dilation (FMD), a predictor of atherosclerosis and increased cardiovascular risk, was not different among tobacco cigarette (TC) smokers or electronic cigarette (EC) vapers who had refrained from smoking, compared with nonsmokers. However, acutely smoking one TC impaired FMD in smokers, whereas vaping a similar EC "dose" (as estimated by change in plasma nicotine levels) did not. Finally, although it is reassuring that acute EC vaping did not acutely impair FMD, it would be premature and dangerous to conclude that ECs do not lead to atherosclerosis or increase cardiovascular risk.


Assuntos
Artéria Braquial/fisiopatologia , Fumar Cigarros/efeitos adversos , Vapor do Cigarro Eletrônico/efeitos adversos , Sistemas Eletrônicos de Liberação de Nicotina , Endotélio Vascular/fisiopatologia , Vaping/efeitos adversos , Vasodilatação , Adulto , Aterosclerose/etiologia , Aterosclerose/fisiopatologia , Fumar Cigarros/fisiopatologia , Qualidade de Produtos para o Consumidor , Estudos Cross-Over , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória , Medição de Risco , Fatores de Risco , Adulto Jovem
13.
Am J Physiol Heart Circ Physiol ; 318(5): H1176-H1184, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32196360

RESUMO

Tobacco cigarette smoking is associated with increased sudden death risk, perhaps through adverse effects on ventricular repolarization. The effect of electronic (e-)cigarettes on ventricular repolarization is unknown. The objective of the study was to test the hypothesis that tobacco cigarettes and e-cigarettes have similar adverse effects on electrocardiogram (ECG) indexes of ventricular repolarization and these effects are attributable to nicotine. ECG recordings were obtained in 37 chronic tobacco cigarette smokers, 43 chronic e-cigarette users, and 65 nonusers. Primary outcomes, Tpeak to Tend (Tp-e), Tp-e/QT ratio, and Tp-e/QTc ratio, were measured in tobacco cigarette smokers pre-/post-straw control and smoking one tobacco cigarette and in e-cigarette users and nonusers pre-/post-straw control and using an e-cigarette with and without nicotine (different days). Mean values of the primary outcomes were not different among the three groups at baseline. In chronic tobacco cigarette smokers, all primary outcomes, including the Tp-e (12.9 ± 5.0% vs. 1.5 ± 5%, P = 0.017), Tp-e/QT (14.9 ± 5.0% vs. 0.7 ± 5.1%, P = 0.004), and Tp-e/QTc (11.9 ± 5.0% vs. 2.1 ± 5.1%, P = 0.036), were significantly increased pre-/post-smoking one tobacco cigarette compared with pre-/post-straw control. In chronic e-cigarette users, the Tp-e/QT (6.3 ± 1.9%, P = 0.046) was increased only pre/post using an e-cigarette with nicotine but not pre/post the other exposures. The changes relative to the changes after straw control were greater after smoking the tobacco cigarette compared with using the e-cigarette with nicotine for Tp-e (11.4 ± 4.4% vs. 1.1 ± 2.5%, P < 0.05) and Tp-e/QTc (9.8 ± 4.4% vs. -1.6 ± 2.6%, P = 0.05) but not Tp-e/QT(14.2 ± 4.5% vs. 4.2 ± 2.6%, P = 0.061) . Heart rate increased similarly after the tobacco cigarette and e-cigarette with nicotine. Baseline ECG indexes of ventricular repolarization were not different among chronic tobacco cigarette smokers, electronic cigarette users and nonusers. An adverse effect of acute tobacco cigarette smoking on ECG indexes of ventricular repolarization was confirmed. In chronic e-cigarette users, an adverse effect of using an e-cigarette with nicotine, but not without nicotine, on ECG indexes of ventricular repolarization was also observed.NEW & NOTEWORTHY Abnormal ventricular repolarization, as indicated by prolonged Tpeak-end (Tp-e), is associated with increased sudden death risk. Baseline ECG indexes of repolarization, Tp-e, Tp-e/QT, and Tp-e/QTc, were not different among tobacco cigarette (TC) smokers, electronic cigarette (EC) users, and nonsmokers at baseline, but when TC smokers smoked one TC, all parameters were prolonged. Using an electronic cigarette with nicotine, but not without nicotine, increased the Tp-e/QT. Smoking induces changes in ECG indexes of ventricular repolarization associated with increased sudden death risk.


Assuntos
Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Fumar Tabaco/fisiopatologia , Vaping/fisiopatologia , Função Ventricular/efeitos dos fármacos , Potenciais de Ação , Adulto , Morte Súbita Cardíaca/etiologia , Feminino , Frequência Cardíaca , Humanos , Masculino , Fumar Tabaco/efeitos adversos , Vaping/efeitos adversos
14.
Am J Physiol Heart Circ Physiol ; 319(2): H262-H270, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32559135

RESUMO

Electronic cigarettes (ECs) and tobacco cigarettes (TCs) both release nicotine, a sympathomimetic drug. We hypothesized that baseline heart rate variability (HRV) and hemodynamics would be similar in chronic EC and TC smokers and that after acute EC use, changes in HRV and hemodynamics would be attributable to nicotine, not non-nicotine, constituents in EC aerosol. In 100 smokers, including 58 chronic EC users and 42 TC smokers, baseline HRV and hemodynamics [blood pressure (BP) and heart rate (HR)] were compared. To isolate the acute effects of nicotine vs. non-nicotine constituents in EC aerosol, we compared changes in HRV, BP, and HR in EC users after using an EC with nicotine (ECN), EC without nicotine (EC0), nicotine inhaler (NI), or sham vaping (control). Outcomes were also compared with TC smokers after smoking one TC. Baseline HRV and hemodynamics were not different in chronic EC users and TC smokers. In EC users, BP and HR, but not HRV outcomes, increased only after using the ECN, consistent with a nicotine effect on BP and HR. Similarly, in TC smokers, BP and HR but not HRV outcomes increased after smoking one TC. Despite a similar increase in nicotine, the hemodynamic increases were significantly greater after TC smokers smoked one TC compared with the increases after EC users used the ECN. In conclusion, chronic EC and TC smokers exhibit a similar pattern of baseline HRV. Acute increases in BP and HR in EC users are attributable to nicotine, not non-nicotine, constituents in EC aerosol. The greater acute pressor effects after TC compared with ECN may be attributable to non-nicotine, combusted constituents in TC smoke.NEW & NOTEWORTHY Chronic electronic cigarette (EC) users and tobacco cigarette (TC) smokers exhibit a similar level of sympathetic nerve activity as estimated by heart rate variability. Acute increases in blood pressure (BP) and heart rate in EC users are attribute to nicotine, not non-nicotine, constituents in EC aerosol. Acute TC smoking increased BP significantly more than acute EC use, despite similar increases in plasma nicotine, suggestive of additional adverse vascular effects attributable to combusted, non-nicotine constituents in TC smoke.


Assuntos
Sistema Cardiovascular/efeitos dos fármacos , Fumar Cigarros/efeitos adversos , Sistemas Eletrônicos de Liberação de Nicotina , Hemodinâmica/efeitos dos fármacos , Nicotina/efeitos adversos , Sistema Nervoso Simpático/efeitos dos fármacos , Simpatomiméticos/efeitos adversos , Vaping/efeitos adversos , Adulto , Aerossóis , Pressão Sanguínea/efeitos dos fármacos , Sistema Cardiovascular/fisiopatologia , Estudos Cross-Over , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Exposição por Inalação/efeitos adversos , Masculino , Pessoa de Meia-Idade , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Distribuição Aleatória , Medição de Risco , Sistema Nervoso Simpático/fisiopatologia , Simpatomiméticos/administração & dosagem , Fatores de Tempo , Adulto Jovem
15.
Liver Int ; 40(9): 2242-2251, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32652744

RESUMO

BACKGROUND & AIMS: Liver fibrosis assessed by liver biopsy is predictive of clinical liver events in patients with nonalcoholic fatty liver disease (NAFLD). Magnetic resonance elastography (MRE) correlates with liver biopsy in assessing liver fibrosis. However, data assessing the relationship between MRE and clinical liver events are lacking. We investigated the association between MRE and clinical liver events/death and identified the cut-off to predict clinical liver events in NAFLD patients. METHODS: We conducted a multicenter retrospective study of NAFLD patients who underwent MRE between 2016 and 2019. Clinical liver events were defined as decompensation events and death. We categorized patients into noncirrhosis, compensated cirrhosis and decompensated cirrhosis. Fisher's exact test was used to test association strength. Receiver operative curve methods were used to determine the optimal cut-off of MRE liver stiffness and to maximize the accuracy for classifying noncirrhosis, compensated cirrhosis and decompensated cirrhosis. Logistic regression modelling was used to predict decompensation. RESULTS: The study included 320 NAFLD patients who underwent MRE. The best threshold for distinguishing cirrhosis from noncirrhosis was 4.39 kPa (AUROC 0.92) and from decompensated cirrhosis was 6.48 kPa (AUROC 0.71). Odds of decompensation increased as liver stiffness increased (OR 3.28) (P < .001). Increased liver stiffness was associated with ascites, hepatic encephalopathy, oesophageal variceal bleeding and mortality (median 7.10, 10.15 and 10.15 kPa respectively). CONCLUSION: In NAFLD patients, liver stiffness measured by MRE with a cut-off of ≥6.48 kPa is associated with decompensation and mortality, and specific MRE cut-offs are predictive of individual clinical liver events.


Assuntos
Técnicas de Imagem por Elasticidade , Varizes Esofágicas e Gástricas , Hepatopatia Gordurosa não Alcoólica , Biópsia , Varizes Esofágicas e Gástricas/patologia , Hemorragia Gastrointestinal/patologia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Imageamento por Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia , Estudos Prospectivos , Curva ROC , Estudos Retrospectivos
16.
Clin Auton Res ; 30(6): 507-519, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32219640

RESUMO

PURPOSE: Electronic cigarettes (ECs) are the fastest growing tobacco product in the USA, and ECs, like tobacco cigarettes (TCs), have effects on the cardiovascular autonomic nervous system, with clinical implications. The purpose of this review was to collect and synthesize available studies that have investigated the autonomic cardiovascular effects of EC use in humans. Special attention is paid to the acute and chronic effects of ECs, the relative contributions of the nicotine versus non-nicotine constituents in EC emissions and the relative effects of ECs compared to TCs. METHODS: Using the methodology described in the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement, we conducted a literature search of the Ovid PubMed and Embase databases on 6 December 2019 using keywords in titles and abstracts of published literature. Acute (minutes to hours) and chronic (days or longer) changes in heart rate variability (HRV), heart rate (HR) and blood pressure (BP) were used as estimates of cardiovascular autonomic effects. RESULTS: Nineteen studies were included in this systematic review, all of which used earlier generation EC devices. Acute EC vaping increased HR and BP less than acute TC smoking. Nicotine but not non-nicotine constituents in EC aerosol were responsible for the sympathoexcitatory effects. The results of chronic EC vaping studies were consistent with a chronic sympathoexcitatory effect as estimated by HRV, but this did not translate into chronic increases in HR or BP. CONCLUSIONS: Electronic cigarettes are sympathoexcitatory. Cardiac sympathoexcitatory effects are less when vaping using the earlier generation ECs than when smoking TCs. Additional studies of the latest pod-like EC devices, which deliver nicotine similarly to a TC, are necessary.


Assuntos
Fármacos do Sistema Nervoso Autônomo , Sistema Cardiovascular , Sistemas Eletrônicos de Liberação de Nicotina , Vaping , Humanos , Nicotina/efeitos adversos , Vaping/efeitos adversos
17.
Stroke ; 50(9): 2433-2440, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31311465

RESUMO

Background and Purpose- Quantifying the benefit magnitude of combined endovascular thrombectomy (EVT) and intravenous thrombolysis (IVT) versus nonreperfusion care in patients with acute ischemic stroke caused by large vessel occlusion would aid organization of regional stroke care systems. Methods- NINDS rt-PA Study (National Institute for Neurological Disorders and Stroke Recombinant Tissue Plasminogen Activator) and SWIFT PRIME trial (Solitaire With the Intention for Thrombectomy as Primary Endovascular Treatment) patients were matched for prognosis (based on age and National Institutes of Health Stroke Scale) and definite/likely anterior circulation large vessel occlusion (based on National Institutes of Health Stroke Scale total score and item pattern), using optimal inverse variance matching, to determine comparative outcomes with nonreperfusion care alone, IVT alone, and IVT+EVT. Results- Matching yielded 240 patients, including 80 each treated with nonreperfusion care, IVT alone, and IVT+EVT, with, respectively, mean age 67.1, 67.1, and 66.9 and presenting deficit severity (National Institutes of Health Stroke Scale) mean 15.8, 15.9, and 15.9. Outcomes at 3 months for IVT+EVT versus nonreperfusion care included freedom from disability (modified Rankin Scale score, 0-1) 48.1% versus 21.3%, P=0.0004; functional independence (modified Rankin Scale score, 0-2) 62.9% versus 32.6, P=0.0001; and reduced disability over all 7 modified Rankin Scale levels, common odds ratio 3.34, P<0.0001. Outcomes for IVT alone versus nonreperfusion care included: freedom from disability 30.0% versus 21.3%, P=0.28 and reduced disability over all 7 modified Rankin Scale levels, common odds ratio 1.14, P=0.65. Compared with nonreperfusion care, the number needed to treat with EVT+IVT for 1 more patient to have reduced disability was 1.8. Conclusions- Matched patient analysis across randomized trials provides evidence that the strategy of combined IVT and mechanical thrombectomy is a highly beneficial treatment strategy for acute ischemic stroke caused by large vessel occlusion patients. A reasonable effect magnitude estimate is that, among every 100 patients treated, combined IVT+EVT reperfusion therapy, compared with no reperfusion therapy, reduces long-term disability in 57, including conferring functional independence upon 30.


Assuntos
Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/métodos , Fibrinólise/fisiologia , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Idoso , Isquemia Encefálica/diagnóstico por imagem , Terapia Combinada/métodos , Terapia Combinada/tendências , Procedimentos Endovasculares/tendências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Trombectomia/tendências
18.
Stroke ; 50(10): 2892-2901, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31480966

RESUMO

Background and Purpose- Brain electrical stimulation, widely studied to facilitate recovery from stroke, has also been reported to confer direct neuroprotection in preclinical models of acute cerebral ischemia. Systematic review of controlled preclinical acute cerebral ischemia studies would aid in planning for initial human clinical trials. Methods- A systematic Medline search identified controlled, preclinical studies of central nervous system electrical stimulation in acute cerebral ischemia. Studies were categorized among 6 stimulation strategies. Three strategies applied different stimulation types to tissues within the ischemic zone (cathodal hemispheric stimulation [CHS], anodal hemispheric stimulation, and pulsed hemispheric stimulation), and 3 strategies applied deep brain stimulation to different neuronal targets remote from the ischemic zone (fastigial nucleus stimulation, subthalamic vasodilator area stimulation, and dorsal periaqueductal gray stimulation). Random-effects meta-analysis assessed electrical stimulation modification of final infarct volume. Study-level risk of bias and intervention-level readiness-for-translation were assessed using formal rating scales. Results- Systematic search identified 28 experiments in 21 studies, including a total of 350 animals, of electrical stimulation in preclinical acute cerebral ischemia. Overall, in animals undergoing electrical stimulation, final infarct volumes were reduced by 37% (95% CI, 34%-40%; P<0.001), compared with control. There was evidence of heterogeneity of efficacy among stimulation strategies (I2=93.1%, Pheterogeneity<0.001). Among the within-ischemic zone stimulation strategies, only CHS significantly reduced the infarct volume (27 %; 95% CI, 22%-33%; P<0.001); among the remote-from ischemic zone approaches, all (fastigial nucleus stimulation, subthalamic vasodilator area stimulation, and dorsal periaqueductal gray stimulation) reduced infarct volumes by approximately half. On formal rating scales, CHS studies had the lowest risk of bias, and CHS had the highest overall quality of intervention-level evidence supporting readiness to proceed to clinical testing. Conclusions- Electrical stimulation reduces final infarct volume across preclinical studies. CHS shows the most robust evidence and is potentially appropriate for progression to early-stage human clinical trial testing as a promising neuroprotective intervention.


Assuntos
Isquemia Encefálica/patologia , Estimulação Elétrica/métodos , Acidente Vascular Cerebral/patologia , Animais , Modelos Animais de Doenças , Camundongos
19.
Prenat Diagn ; 39(3): 200-208, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30488473

RESUMO

OBJECTIVES: The objectives of this study are to develop gestational age-specific growth curves for fetal third metacarpal and phalangeal lengths and to determine if fetal hand proportion is established in utero. METHODS: This prospective cross-sectional study used 2D ultrasound across gestational ages 12 to 39 weeks to evaluate the third fetal metacarpal and phalangeal measurements. Gestational age-specific reference growth curves were developed. Associations between continuous variables were assessed using Spearman correlations (rs ) and restricted cubic splines. A nonlinear biologic regression model was used to predict metacarpal and phalangeal lengths as a function of gestational age. Measurements derived from five cases of thanatophoric dysplasia were used to determine if brachydactyly could be objectified. RESULTS: Fetal metacarpal and phalangeal lengths are highly correlated across gestational age (rs  = 0.96, P < 0.001). The mean fetal metacarpal to phalangeal ratio is constant from gestational age 15 to 39 weeks (rs  = -0.07, P = 0.49). Third-digit metacarpal and phalangeal lengths in thanatophoric dysplasia showed brachydactyly in all cases (5/5), and none of the cases (0/5) demonstrated a normal metacarpal to phalangeal ratio of 0.49. CONCLUSION: We present gestational age-specific reference growth curves for fetal third metacarpal and phalangeal lengths, which may be used to detect brachydactyly. We demonstrate a prenatal metacarpal to phalangeal ratio of 1:2.


Assuntos
Padronização Corporal , Falanges dos Dedos da Mão/embriologia , Gráficos de Crescimento , Ossos Metacarpais/embriologia , Adulto , Biometria , Estudos Transversais , Feminino , Falanges dos Dedos da Mão/diagnóstico por imagem , Idade Gestacional , Humanos , Ossos Metacarpais/diagnóstico por imagem , Gravidez , Estudos Prospectivos
20.
Stroke ; 49(2): 348-354, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29301973

RESUMO

BACKGROUND AND PURPOSE: Increased blood pressure (BP) variability, in addition to high BP, may contribute to adverse outcome in intracerebral hemorrhage. However, degree and association with outcome of BP variability (BPV) in the hyperacute period, 15 minutes to 5 hours after onset, have not been delineated. METHODS: Among consecutive patients with intracerebral hemorrhage enrolled in the FAST-MAG trial (Field Administration of Stroke Therapy-Magnesium), BPs were recorded by paramedics in the field and during the first 24 hours of hospital course. BP was analyzed in the hyperacute period, from 0 to 4-6 hours, and in the acute period, from 0 to 24-26 hours after onset. BPV was analyzed by SD, coefficient of variation, and successive variation. RESULTS: Among 386 patients with intracerebral hemorrhage, first systolic BP at median 23 minutes (interquartile range, 14-38.5) after onset was median 176 mm Hg, second systolic BP on emergency department arrival at 57 minutes (interquartile range, 45-75) after onset was 178 mm Hg, and systolic BP 24 hours after arrival was 138 mm Hg. Unfavorable outcome at 3 months (modified Rankin Scale, 3-6) occurred in 270 (69.9%). Neither mean nor maximum systolic BP was associated with outcome in multivariable analysis. However, all 3 parameters of BPV, in both the hyperacute and the acute stages, were associated with poor outcome. In the hyperacute phase, BPV was associated with poor outcome with adjusted odds ratios of 3.73 for the highest quintile of SD, 4.78 for the highest quintile of coefficient of variation, and 3.39 for the highest quintile of successive variation. CONCLUSIONS: BPV during the hyperacute first minutes and hours after onset in patients with intracerebral hemorrhage was independently associated with poor functional outcome. Stabilization of BPV during this vulnerable period, in the pre-hospital and early emergency department course, is a potential therapeutic target for future clinical trials. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059332.


Assuntos
Pressão Sanguínea/fisiologia , Hemorragia Cerebral/fisiopatologia , Idoso , Anti-Hipertensivos/uso terapêutico , Determinação da Pressão Arterial/métodos , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/etiologia , Feminino , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/tratamento farmacológico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA