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BACKGROUND: Low-dose direct oral anticoagulant (DOAC) use is quite prevalent in clinical practice, but evidence of its effectiveness and safety compared with high-dose DOAC in patients with atrial fibrillation (AF) remains limited. We aimed to assess the effectiveness and safety of low-dose and high-dose DOACs in patients with AF with similar baseline characteristics. METHODS: We used a cohort of hospitalized patients with a primary or secondary diagnosis of AF after discharge to the community, whose data were stored in the Quebec administrative databases, from 2011 to 2017. Older adults with AF newly prescribed with rivaroxaban (15 or 20 mg) or apixaban (2.5 mg or 5 mg) were classified as under treatment (UT) and intent to treat (ITT). We used an inverse probability treatment weighting study of new users of rivaroxaban and apixaban to address confounding by indication. The primary effectiveness outcome was ischemic stroke/systemic embolism (SE), while the primary safety outcome was major bleeding (MB). We used Cox proportional models to estimate the marginal hazard ratios (HRs). FINDINGS: A total of 1,722 and 4,639 patients used low-dose and standard-dose rivaroxaban, respectively, while 3,833 and 6,773 patients used low-dose and standard-dose apixaban, respectively. No significant difference was observed in the incidence of comparative stroke/SE and MB between low-dose and standard-dose rivaroxaban, except for the risk of acute myocardial infarction (AMI), which was increased with the low dose in the UT analysis. For apixaban, no difference was found in the bleeding rates, but the risk of stroke/SE (HR: 1.95; 95% confidence interval (CI): 1.38-2.76) and death (HR: 1.99; 95% CI: 1.46-2.70) were greater in the low-dose group than in the standard-dose group in the UT analysis. Similar results were observed for the ITT analysis. CONCLUSION: No significant differences were observed in the effectiveness or safety outcome between low-dose and standard-dose rivaroxaban, except for AMI. However, low-dose apixaban was associated with a greater risk of stroke/SE and death without a reduction in the bleeding rates.
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Fibrilação Atrial , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Idoso , Rivaroxabana/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Piridonas/efeitos adversos , Anticoagulantes , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controleRESUMO
INTRODUCTION: Previous analysis of registered clinical trials has found a number of protocols result in changes in the registered primary outcome measures. This investigation determined if reported primary outcomes in chiropractic-related clinical trials registered in clinicaltrials.gov match their published results. Additionally, we assessed secondary outcomes, publication status and whether raw data were posted to the registry. METHODS: Clinicaltrials.gov was searched for chiropractic-related trials and having a completed status. If the study was published, outcome measures were compared between the clinicaltrials.gov entry and the published paper to assess for consistency. RESULTS: Within clinicaltrials.gov 171 chiropracticrelated protocols were identified with 102 of those published (59.6% publication rate). Ninety-two of the published papers (90.2%) had agreement between their primary outcome and the entry on clinicaltrials.gov and 82 (80.4%) agreed with the secondary outcomes. CONCLUSION: A modest rate of agreement between clinicaltrials.gov entries and the published papers was found. While chiropractic-related clinical trials are fewer compared to medical trials, chiropractic-related research has a substantially better rate of primary and secondary outcome concordance with registered protocols.
INTRODUCTION: En examinant des essais cliniques enregistrés, on s'est rendu compte qu'un certain nombre de protocoles faisaient varier les résultats principaux. On a mené une étude pour savoir si les résultats primaires d'essais cliniques sur la chiropratique enregistrés sur clinicaltrials.gov correspondaient à ceux publiés. On a aussi examiné les résultats secondaires, l'état de publication et cherché à savoir si les données brutes étaient publiées dans le registre. MÉTHODOLOGIE: Dans la base de données Clinicaltrials.gov, on a repéré des essais cliniques sur la chiropratique qui étaient terminés. Lorsque l'essai clinique avait été publié, on a comparé les résultats au moment de son enregistrement sur clinicaltrials.gov à ceux parus dans des publications pour savoir s'ils concordaient. RÉSULTATS: Sur le site clinicaltrials.gov, on a trouvé 171 études sur la chiropratique, dont 102 avaient été publiés (taux de publication:59,6 %). Pour quatrevingt-douze publications (90,2 %), on a observé une concordance entre les résultats primaires au moment de l'enregistrement sur clinicaltrials.gov et 82 (80,4 %) et les résultats secondaires. CONCLUSION: On a observé un taux modeste de concordance entre les données à l'enregistrement sur clinicaltrails.gov et les données publiées. Les essais cliniques sur la chiropratique sont moins nombreux que des essais cliniques de médicaments. Mais le taux de concordance entre les résultats primaires et les résultats secondaires était considérablement plus élevé lorsque les protocoles de recherches sur la chiropratique sont enregistrés.
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AIM: Real-world predictors of major bleeding (MB) have been well-studied among warfarin users, but not among all direct oral anticoagulant (DOAC) users diagnosed with atrial fibrillation (AF). Thus, our goal was to build a predictive model of MB for new users of all oral anticoagulants (OAC) with AF. METHODS: We identified patients hospitalized for any cause and discharged alive in the community from 2011 to 2017 with a primary or secondary diagnosis of AF in Quebec's RAMQ and Med-Echo administrative databases. Cohort entry occurred at the first OAC claim. Patients were categorized according to OAC type. Outcomes were incident MB, gastrointestinal bleeding (GIB), non-GI extracranial bleeding (NGIB) and intracranial bleeding within 1 year of follow-up. Covariates included age, sex, co-morbidities (within 3 years before cohort entry) and medication use (within 2 weeks before cohort entry). We used logistic-LASSO and adaptive logistic-LASSO regressions to identify MB predictors among OAC users. Discrimination and calibration were assessed for each model and a global model was selected. Subgroup analyses were performed for MB subtypes and OAC types. RESULTS: Our cohort consisted of 14,741 warfarin, 3,722 dabigatran, 6,722 rivaroxaban and 11,196 apixaban users aged 70-86 years old. The important MB predictors were age, prior MB and liver disease with ORs ranging from 1.37-1.64. The final model had a c-statistic of 0.63 (95% CI 0.60-0.65) with adequate calibration. The GIB and NGIB models had similar c-statistics of 0.65 (95% CI 0.63-0.66) and 0.67 (95% CI 0.64-0.70), respectively. CONCLUSIONS: MB and MB subtype predictors were similar among DOAC and warfarin users. The predictors selected by our models and their discriminative potential are concordant with published data. Thus, these models can be useful tools for future pharmacoepidemiologic studies involving older oral anticoagulant users with AF.
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Anticoagulantes/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Hemorragia/classificação , Hemorragia/epidemiologia , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Dabigatrana/administração & dosagem , Dabigatrana/efeitos adversos , Bases de Dados Factuais , Feminino , Hemorragia Gastrointestinal/induzido quimicamente , Hemorragia Gastrointestinal/epidemiologia , Hemorragia/induzido quimicamente , Hospitalização , Humanos , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/epidemiologia , Masculino , Pirazóis/administração & dosagem , Pirazóis/efeitos adversos , Piridonas/administração & dosagem , Piridonas/efeitos adversos , Análise de Regressão , Rivaroxabana/administração & dosagem , Rivaroxabana/efeitos adversos , Varfarina/administração & dosagem , Varfarina/efeitos adversosRESUMO
STUDY OBJECTIVE: Observational studies assessing direct oral anticoagulant (DOACs) dosage in atrial fibrillation (AF) reported that a lower proportion of patients received high-dose DOACs compared to those in randomized controlled trials (RCTs). Effectiveness and safety of high-dose DOACs relative to apixaban in a real-world AF population need to be addressed. The aim is to assess comparative effectiveness and safety of high-dose rivaroxaban relative to apixaban. DESIGN: We conducted a cohort study. Setting We built a cohort of patients hospitalized and discharged in community with a primary or secondary AF diagnosis from 2011-2017 using Quebec administrative databases (Med-Echo and RAMQ). Patients Cohort entry was defined as the first OAC claim in new users of high-dose rivaroxaban and apixaban, with no OAC claims in the prior year. Intervention To compare effectiveness and safety of high-dose rivaroxaban to apixaban. Measurement We ascertained patient demographics, comorbidities, CHA2DS2-VASc and HASBLED scores and Charlson score within 3 years prior to cohort entry. Primary effectiveness and safety were a composite of ischemic stroke/systemic thrombosis, death, myocardial infarction, and of intracranial bleeding (ICH), extracranial major bleeding, in the first year following drug initiation. We conducted propensity score matching and estimated hazard ratios (HRs) for outcomes using Cox proportional hazard models. All the analyses were conducted to account for competing risks. Main results The cohort consisted of 4,632 and 6,771 patients received high-dose rivaroxaban and apixaban, respectively. High-dose rivaroxaban users were younger with a mean age of 73.2 years, presented less associated comorbidities and had lower CHA2DS2-VASc scores compared to apixaban. High-dose rivaroxaban at the intention to treat was associated with a higher risk of stroke/SE/death (HR 1.21, 95% CI 1.04-1.40) and worse composite effectiveness (HR 1.21: 1.05-1.40); under treatment exposure, those values were at HR (1.66: 1.21-2.29) and HR (1.58:1.19-2.10), respectively. And, rivaroxaban presented a less favorable safety profile relative to apixaban. Conclusion In this study, composite effectiveness and safety varied between rivaroxaban and apixaban. High-dose apixaban was observed to have a better effectiveness and safety.
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Fibrilação Atrial , Pirazóis , Piridonas , Rivaroxabana , Idoso , Fibrilação Atrial/tratamento farmacológico , Estudos de Coortes , Relação Dose-Resposta a Droga , Humanos , Pontuação de Propensão , Pirazóis/administração & dosagem , Pirazóis/efeitos adversos , Piridonas/administração & dosagem , Piridonas/efeitos adversos , Rivaroxabana/administração & dosagem , Rivaroxabana/efeitos adversos , Resultado do TratamentoRESUMO
Aims: Observational studies of various dose levels of direct oral anticoagulants (DOACs) for patients with atrial fibrillation (AF) found that a high proportion of patients received a dose lower than the target dose tested in randomized controlled trials. There is a need to compare low-dose DOACs with warfarin or other DOACs on effectiveness and safety. Methods: Using administrative data from Quebec province, Canada, we built a cohort of new warfarin or DOAC users discharged from hospital between 2011 and 2017. We determined CHA2DS2-VASc and HAS-BLED scores, and comorbidities for 3-year prior cohort entry. The primary effectiveness endpoint was a composite of ischemic stroke/systemic embolism (SE), and secondary outcomes included a safety composite of major bleeding (MB) events and effectiveness composite (stroke/SE, death) at 1-year follow-up. We contrasted each low-dose DOAC with warfarin or other DOACs as references using inverse probability of treatment weighting to estimate marginal Cox hazard ratios (HRs). Results: The cohort comprised 22,969 patients (mean age: 80-86). We did not find a significant risk reduction for the stroke/SE primary effectiveness endpoint for DOACs vs. warfarin; however, we observed a significantly lower risk for low-dose dabigatran vs. warfarin (HR [95%CI]: 0.59 [0.42-0.81]) for effectiveness composite, mainly due to a lower death rate. The differences in effectiveness and safety composites between low-dose rivaroxaban vs. warfarin were not significant. However, low-dose apixaban had a better safety composite (HR: 0.68 [0.53-0.88]) vs. warfarin. Comparisons of dabigatran vs. apixaban showed a lower risk of stroke/SE (HR: 0.53 [0.30-0.93]) and a 2-fold higher risk of MB. The MB risk was higher for rivaroxaban than for apixaban (HR: 1.58 [1.09-2.29]). Conclusions: The results of this population-based study suggest that low-dose dabigatran has a better effective composite than warfarin. Compared with apixaban, low-dose dabigatran had a better effectiveness composite but a worse safety profile. Low-dose apixaban had a better safety composite than warfarin and other low-dose DOACs. Given that the comparative effectiveness and safety seem to vary from one DOAC to another, pharmacokinetic data for specific populations are now warranted.
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BACKGROUND AND PURPOSE: Data on oral anticoagulant (OAC) uptake and pattern of use are limited. Real-life data in patients with atrial fibrillation (AF) are important for understanding patient exposure. A cohort study of new OAC users was built to assess trends of drug use from 2011 to 2017, persistence rate, switching rate, adherence level, and predictors of adherence. METHODS: We built a cohort using the Régie d'Assurance Maladie du Québec (RAMQ) and Med-Echo administrative databases of new adult OAC users within 1 year following hospitalization with a diagnosis of AF. New users of OAC were defined as having no OAC claims in the year before cohort entry. We assessed trends of OAC use; persistence rate, defined as a gap between refills of no longer than two times the duration of the previous prescriptions; and adherence level, defined as the proportion of days covered (PDC) over a 1-year period following initiation. Predictors of nonadherence (PDC less than 80%) were analyzed using logistic regression models. RESULTS: The cohort consisted of 33,311 incident OAC users. Of total OAC claims, the proportions of warfarin claims decreased from 77.9% in 2011 to 12.7% in 2017, with direct oral anticoagulants (DOACs) accounting for 87.3% of claims, of which apixaban and rivaroxaban accounted for 60.1% and 23.4%, respectively, by the end of 2017. One year after OAC initiation, persistence rates ranged from 53% with warfarin to 77% with a high dose of apixaban. Approximately 75% of incident OAC users were considered "adherent" (PDC 80% or more), with a mean PDC of 95.6-98.1%, compared with "nonadherent," with a mean PDC varying between 43.1% and 50.7%. Older age, female sex, higher CHA2 DS2 -VASc score (to predict thromboembolic risk in AF), prior stroke, and treatment with chronic cardiovascular disease drugs were associated with high adherence levels. CONCLUSION: The clinical uptake of DOACs increased over time, accounting for 87.3% of prescriptions in 2017. In our study, 25% of new OAC users presented a low adherence level. Adherence to OACs remains a significant challenge in patients with AF.
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Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Padrões de Prática Médica/tendências , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/sangue , Estudos de Coortes , Feminino , Humanos , Revisão da Utilização de Seguros , Masculino , Quebeque , Estudos Retrospectivos , Varfarina/uso terapêuticoRESUMO
OBJECTIVE: To estimate national and geography-based variations in blood pressure and burden of hypertension in Cameroon, generally called 'miniature Africa'. METHODS: PubMed, Medline, EMBASE, CINHAL, Web of Science, Popline, Scopus and BDSP were searched through November 2018, for hypertension studies among Cameroonians aged at least 18 years. Hypertension was measured as SBP at least 140âmmHg or DBP at least 90âmmHg. Random-effects meta-analysis was used. RESULTS: Twenty studies involving 46â491 participants met inclusion criteria. Overall hypertension prevalence was 30.9% [95% confidence interval (CI) 27.0-34.8]: 29.6% (24.1-35.1) and 32.1% (27.2-37.1) in 1994-2010 and 2011-2018, respectively. Of hypertensive participants, only 24.4% (18.9-30.0) - 31.6% (21.0-42.3) and 20.8% (14.0-27.7) in 1994-2010 and 2011-2018, respectively - were aware of their status, 15.1% (10.6-19.6) were taking antihypertensive medications and 8.8% (5.7-11.9) - 10.4% (7.5-13.3) and 8.3% (4.4-12.3) in 1994-2010 and 2011-2018, respectively - were controlled. Hypertension prevalence varied by sex: 34.3% (30.0-38.6) for men and 31.3% (26.5-36.1) for women; ethnicity: from 3.3% (0.4-6.2) among Pygmies to 56.6% (49.4-63.8) among Bamileke; urbanity: 25.4% (17.1-33.7) for rural and 31.4% (27.3-35.5) for urban dwellers; agroecological zone: from 35.1% (28.9-41.3) in Tropical highlands to 28% (20.1-35.9) in Guinea-Savannah; and subnational region: from 36.3% (27.8-44.9) in the West to 17.1% (9.9-44.2) in the South. CONCLUSION: Cameroon's hypertension prevalence is high and increasing whereas awareness, treatment and control are low and declining. Emerging patterns call urgently for effective campaigns to raise hypertension awareness alongside strategies for hypertension prevention and BP control.
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Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Hipertensão/epidemiologia , Camarões/epidemiologia , Etnicidade , Humanos , Hipertensão/tratamento farmacológico , Prevalência , População Rural/estatística & dados numéricosRESUMO
BACKGROUND AND PURPOSE: Patients with nonvalvular atrial fibrillation (NVAF) who survive an intracranial hemorrhage (ICH) have an increased risk of ischemic stroke and systemic embolism (IS/ SE). We investigated whether starting oral anticoagulants (OACs) among older NVAF patients after an ICH was associated with a lower risk of IS/SE and mortality but offset by an increase in major bleeding. METHODS: We assembled a patient cohort from the Quebec Régie de l'Assurance Maladie du Québec (RAMQ) and Med-Echo administrative databases. We identified older adults with NVAF from 1995 to 2015. All patients with incident ICH and discharged in community were included. Patients were categorized according to OAC exposure. Outcomes included IS/SE, all-cause mortality, recurrent ICH and major bleeding after a quarantine period of 6 weeks. Crude event rates were calculated at 1-year of follow-up, and Cox proportional hazard models with a time-dependent binary exposure were used to assess adjusted hazard ratios (AHRs). RESULTS: The cohort of 683 NVAF patients with ICH aged 83 years on average. The rates (per 100 person-years) for IS/SE, death, ICH and major bleeding were 3.3, 40.6, 11.4, and 2.7 for the no OAC group; and 2.6, 16.3, 5.2, and 5.2 for OAC group, respectively. The AHR for IS/SE and death was 0.10 (95% confidence interval [CI], 0.05 to 0.21), 0.43 (95% CI, 0.19 to 0.97) for recurrent ICH and 1.73 (95% CI, 0.71 to 4.20) for major extracranial bleeding comparing OAC exposure to non-exposed. CONCLUSIONS: Initiating OAC after ICH in older individuals with NVAF is associated with a reduction of IS/SE and mortality and a trend in recurrent ICH supporting its use after ICH.
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BACKGROUND: In 2010, we published our stroke prevention clinic's performance as compared to Canadian stroke prevention guidelines. We now compare our clinic's adherence with guidelines to our previous results, following the implementation of an electronic documentation form. METHODS: All new patients referred to our clinic (McGill University Health Center) for recent transient ischemic attack (TIA) or ischemic stroke between 2014 and 2017 were included. We compared adherence to guidelines to our previous report (N=408 patients for period 2008-2010) regarding vascular risk management and treatment. RESULTS: Three hundred and ninety-two patients were included, of which 36% had a TIA and 64% had an ischemic stroke, with a mean age of 70 years and 43% female. Although the more recent cohort has shown a higher proportion of cardioembolic stroke compared to previous (19.1% vs. 14.7%) following new guidelines regarding prolonged cardiac monitoring, increased popularity in CT angiography has not translated into greater proportion of large-artery stroke subtype (26.3% vs. 26.2%). Blood pressure (BP) targets were achieved in 83% compared with 70% in our previous report (p<0.01). Attainment of low-density lipoprotein cholesterol target was also improved in our recent study (66% vs. 46%, p<0.01). No significant difference was found in the consistency of antithrombotic use (97.7% vs. 99.8%, p=0.08). However, there was a decline in smoking cessation (35% vs. 73%, p=0.02). Overall, optimal therapy status was better attained in the present cohort compared to the previous one (52% vs. 22%, p<0.01). The male sex was associated with better attainment of optimal therapy status (odds ratio, 1.61; 95% confidence interval, 1.04-2.51). The number of follow-up visits and the length of follow-up were not associated with attainment of stroke prevention targets. CONCLUSIONS: Our study shows improvement in attainment of therapeutic goals as recommended by Canadian stroke prevention guidelines, possibly attributed in part to the implementation of electronic medical recording in our clinic. Areas for improvement include smoking cessation counseling and diabetes screening.
CONTEXTE: En 2010, nous avons rendu publics les résultats de notre clinique de prévention des AVC en ce qui regarde les lignes directrices canadiennes de prévention des AVC. Suite à la mise en place d'un formulaire d'information électronique, nous voulons maintenant comparer l'adhésion actuelle de notre clinique à ces lignes directrices à celle mesurée en 2010. MÉTHODES: Tous les nouveaux patients adressés à notre clinique (Centre universitaire de santé McGill) pour des cas récents d'ischémie cérébrale transitoire (ICT) ou d'AVC ischémique survenus entre 2014 et 2017 ont été inclus dans cette étude. Nous avons ainsi comparé l'adhésion actuelle aux lignes directrices évoquées ci-haut à celle du précédent rapport (N = 408 patients pour la période allant de 2008 à 2010), et ce, en ce qui concerne la prise en charge du risque vasculaire et les traitements nécessaires. RÉSULTATS: Au total, 392 patients ont été inclus; de ce nombre, 36 % d'entre eux avaient été victimes d'ICT tandis que 64 % avaient été victimes d'un AVC ischémique. Leur âge moyen était de 70 ans et 43 % d'entre eux étaient de sexe féminin. Bien que la cohorte la plus récente, à la suite de l'introduction de nouvelles lignes directrices portant sur la surveillance cardiaque prolongée, ait donné à voir une proportion plus élevée d'AVC d'origine cardio-embolique comparativement à la précédente (19,1 % par opposition à 14,7 %), la popularité croissante de l'angiographie par tomodensitométrie ne s'est pas traduite par une proportion plus grande de sous-types d'AVC affectant de grandes artères (26,3 % de 2014 à 2017 par opposition à 26,2 % de 2008 à 2010). Les valeurs cibles fixées en matière de pression artérielle ont été atteintes dans 83 % des cas comparativement à 70 % des cas dans notre rapport précédent (p < 0,01). L'atteinte de la valeur cible en ce qui concerne le taux de LDL-cholestérol (lipoprotéines de faible intensité) a également été améliorée dans notre plus récent rapport (66 % par opposition à 46 %; p < 0,01). Ajoutons aussi qu'aucune différence notable n'a été observée quant à une utilisation constante d'anti-thrombotiques (97,7 % par opposition à 99,8 %; p = 0,08). Fait à souligner, un déclin dans l'abandon du tabagisme a été noté (35 % par opposition à 73%; p = 0,02). Dans l'ensemble, les conditions d'une guérison optimale (optimal therapy status) ont été davantage atteintes dans la cohorte la plus récente comparativement à celle de 2008 à 2010 (52 % par opposition à 22 %; p < 0,01). Le fait d'être de sexe masculin a été associé à de meilleures conditions de guérison optimale (rapport des cotes: 1,61; IC 95 %, 1,04 2,51). Enfin, mentionnons que le nombre de consultations de suivi et la durée des suivis n'ont pas été associés à l'atteinte de valeurs cibles en matière de prévention des AVC. CONCLUSIONS: Notre étude montre une série d'améliorations dans l'atteinte des objectifs thérapeutiques recommandés par les lignes directrices canadiennes de prévention des AVC. Cela pourrait être en partie attribuable à la mise en place de dossiers médicaux informatisés au sein de notre clinique. Parmi les aspects qui méritent une amélioration, citons l'établissement d'un programme de counseling en ce qui regarde l'abandon du tabagisme et le dépistage du diabète.
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Ataque Isquêmico Transitório/prevenção & controle , Cooperação do Paciente , Guias de Prática Clínica como Assunto/normas , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/psicologia , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , LDL-Colesterol/metabolismo , Estudos de Coortes , Registros Eletrônicos de Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Resultado do TratamentoRESUMO
Phagocytic cells [dendritic cells (DCs), macrophages, monocytes, neutrophils, and mast cells] utilize C-type (Ca2+-dependent) lectin-like (CLEC) receptors to identify and internalize pathogens or danger signals. As monitors of environmental imbalances, CLEC receptors are particularly important in the function of DCs. Activation of the immune system requires, in sequence, presentation of antigen to the T cell receptor (TCR) by DCs, interaction of co-stimulatory factors such as CD40/80/86 on DCs with CD40L and CD28 on T cells, and production of IL-12 and/or IFN-α/ß to amplify T cell differentiation and expansion. Without this sequence of events within an inflammatory environment, or in a different order, antigen-specific T cells become unresponsive, are deleted or become regulatory T cells. Thus, the mode by which CLEC receptors on DCs are engaged can either elicit activation of T cells to achieve an immune response or induce tolerance. This minireview illustrates these aspects with Dectin-1, DEC205, the mannose receptor and CLEC10A as examples.
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Apresentação de Antígeno , Diferenciação Celular/imunologia , Células Dendríticas/imunologia , Tolerância Imunológica , Lectinas Tipo C/imunologia , Antígenos CD/imunologia , Citocinas/imunologia , Humanos , Linfócitos TRESUMO
BACKGROUND: Receptors specific for the sugar N-acetylgalactosamine (GalNAc) include the human type II, C-type lectin receptor macrophage galactose-type lectin/C-type lectin receptor family member 10A (MGL/CLEC10A/CD301) that is expressed prominently by human peripheral immature dendritic cells, dendritic cells in the skin, alternatively-activated (M2a) macrophages, and to lesser extents by several other types of tissues. CLEC10A is an endocytic receptor on antigen-presenting cells and has been proposed to play an important role in maturation of dendritic cells and initiation of an immune response. In this study, we asked whether a peptide that binds in the GalNAc-binding site of CLEC10A would serve as an effective tool to activate an immune response against ovarian cancer. METHODS: A 12-mer sequence emerged from a screen of a phage display library with a GalNAc-specific lectin. The peptide, designated svL4, and a shorter peptide consisting of the C-terminal 6 amino acids, designated sv6D, were synthesized as tetravalent structures based on a tri-lysine core. In silico and in vitro binding assays were developed to evaluate binding of the peptides to GalNAc-specific receptors. Endotoxin-negative peptide solutions were administered by subcutaneous injection and biological activity of the peptides was determined by secretion of cytokines and the response of peritoneal immune cells in mice. Anti-cancer activity was studied in a murine model of ovarian cancer. RESULTS: The peptides bound to recombinant human CLEC10A with high avidity, with half-maximal binding in the low nanomolar range. Binding to the receptor was Ca2+-dependent. Subcutaneous injection of low doses of peptides into mice on alternate days resulted in several-fold expansion of populations of mature immune cells within the peritoneal cavity. Peptide sv6D effectively suppressed development of ascites in a murine ovarian cancer model as a monotherapy and in combination with the chemotherapeutic drug paclitaxel or the immunotherapeutic antibody against the receptor PD-1. Toxicity, including antigenicity and release of cytotoxic levels of cytokines, was not observed. CONCLUSION: sv6D is a functional ligand for CLEC10A and induces maturation of immune cells in the peritoneal cavity. The peptide caused a highly significant extension of survival of mice with implanted ovarian cancer cells with a favorable toxicity and non-antigenic profile.
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Lectinas Tipo C/imunologia , Neoplasias Ovarianas/terapia , Peptídeos/administração & dosagem , Acetilgalactosamina , Animais , Linhagem Celular Tumoral , Citocinas/sangue , Células Dendríticas/imunologia , Feminino , Imunoterapia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias Ovarianas/imunologia , Linfócitos T/imunologiaRESUMO
Over- and undercoagulation with warfarin are associated with hemorrhagic and thromboembolic events, respectively. Genetic and clinical factors affect warfarin response, and the causes of this variability remain unclear. We present descriptive statistics and test for predictors of poor anticoagulation control. The Quebec Warfarin Cohort (QWC) comprises 1059 new warfarin users, with prospective follow-up using telephone questionnaires every 3 months for 1 year, and using healthcare administrative databases (RAMQ and Med-Echo) for 5 years prior to cohort entry and up to 10 years following active patient participation. Genetic material was collected, and genotyping of CYP2C9 and VKORC1 genes was conducted. Measured outcomes included the percentage of time patients spent within therapeutic range, anticoagulation control, warfarin dose, bleeding, and thromboembolic events. We report baseline characteristics and outcomes after 1 year of follow-up. Poor anticoagulation control was defined as time in therapeutic range <60% in the 3- to 12-month interval. Participants had a mean age of 71 years, and 62% were men. The most common indication for warfarin was atrial fibrillation (87%). Mean time in therapeutic range was 56% (±25%) in the 3 months following warfarin initiation, and 70% (±21%) in the 3- to 12-month interval. During follow-up, the rate of stroke or systemic embolism was 1.8 events per 100 person-years; for major bleeding events, 3.3 events per 100 person-years. Independent predictors of poor anticoagulation control were chronic kidney disease, heart failure, dyslipidemia, and age. The QWC represents a good research cohort to investigate clinical and genetic factors in a warfarin-anticoagulated population.
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Anticoagulantes/administração & dosagem , Coagulação Sanguínea/efeitos dos fármacos , Tromboembolia/prevenção & controle , Varfarina/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Protocolos Clínicos , Citocromo P-450 CYP2C9/genética , Citocromo P-450 CYP2C9/metabolismo , Bases de Dados Factuais , Feminino , Pesquisas sobre Atenção à Saúde , Hemorragia/induzido quimicamente , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Farmacogenética , Variantes Farmacogenômicos , Dados Preliminares , Estudos Prospectivos , Quebeque , Projetos de Pesquisa , Fatores de Risco , Tromboembolia/sangue , Tromboembolia/etiologia , Fatores de Tempo , Resultado do Tratamento , Vitamina K Epóxido Redutases/genética , Vitamina K Epóxido Redutases/metabolismo , Varfarina/efeitos adversosRESUMO
BACKGROUND: Rapid assessment and management of transient ischemic attacks and nondisabling strokes by specialized stroke prevention services reduces the risk of recurrent stroke and improves outcomes. In Canada, with its vast geography and with 16.8% of the population living in rural areas, access to these services is challenging, and considerable variation in access to care exists. The purpose of this multiphase study was to identify sites across Canada providing stroke prevention services, evaluate resource capacity and determine geographic access for Canadians. METHODS: We developed a Stroke Prevention Services Resource Inventory that contained 22 questions on the organization and delivery of stroke prevention services and quality monitoring. The inventory ran from November 2015 to January 2016 and was administered online. We conducted a geospatial analysis to estimate access by drive times. Considerations were made for hours of operation and access within and across provincial borders. RESULTS: A total of 123 stroke prevention sites were identified, of which 119 (96.7%) completed the inventory. Most (95) are designated stroke prevention or rapid assessment clinics. Of the 119 sites, 68 operate full time, and 39 operate less than 2.5 days per week. A total of 87.3% of the Canadian population has access to a stroke prevention service within a 1-hour drive; however, only 69.2% has access to a service that operates 5-7 days a week. Allowing provincial border crossing improves access (< 6-h drive) for those who are beyond a 6-hour drive within their home province (3.4%). INTERPRETATION: Most Canadians have reasonable geographic access to stroke prevention services. Allowing patients to cross borders improves the existing access for many, particularly some remote communities along the Ontario-Quebec and British Columbia-Alberta borders.
RESUMO
The 2017 update of The Canadian Stroke Best Practice Recommendations for the Secondary Prevention of Stroke is a collection of current evidence-based recommendations intended for use by clinicians across a wide range of settings. The goal is to provide guidance for the prevention of ischemic stroke recurrence through the identification and management of modifiable vascular risk factors. Recommendations include those related to diagnostic testing, diet and lifestyle, smoking, hypertension, hyperlipidemia, diabetes, antiplatelet and anticoagulant therapies, carotid artery disease, atrial fibrillation, and other cardiac conditions. Notable changes in this sixth edition include the development of core elements for delivering secondary stroke prevention services, the addition of a section on cervical artery dissection, new recommendations regarding the management of patent foramen ovale, and the removal of the recommendations on management of sleep apnea. The Canadian Stroke Best Practice Recommendations include a range of supporting materials such as implementation resources to facilitate the adoption of evidence to practice, and related performance measures to enable monitoring of uptake and effectiveness of the recommendations. The guidelines further emphasize the need for a systems approach to stroke care, involving an interprofessional team, with access to specialists regardless of patient location, and the need to overcome geographic barriers to ensure equity in access within a universal health care system.
Assuntos
Prática Profissional/normas , Acidente Vascular Cerebral/prevenção & controle , Consumo de Bebidas Alcoólicas/prevenção & controle , Doenças da Aorta/prevenção & controle , Fibrilação Atrial/prevenção & controle , Peso Corporal/fisiologia , Estenose das Carótidas/prevenção & controle , Angiografia por Tomografia Computadorizada , Anticoncepcionais Orais/efeitos adversos , Angiopatias Diabéticas/prevenção & controle , Dieta Saudável , Terapia de Reposição de Estrogênios/efeitos adversos , Exercício Físico/fisiologia , Forame Oval Patente/cirurgia , Estilo de Vida Saudável , Insuficiência Cardíaca/prevenção & controle , Humanos , Hiperlipidemias/prevenção & controle , Hipertensão/prevenção & controle , Drogas Ilícitas/efeitos adversos , Arteriosclerose Intracraniana/prevenção & controle , Ataque Isquêmico Transitório/prevenção & controle , Angiografia por Ressonância Magnética , Imagem Multimodal , Medição de Risco , Fatores de Risco , Prevenção Secundária , Fumar/efeitos adversos , UltrassonografiaRESUMO
BACKGROUND: Hypertension holds a unique place in population health and health care because it is the leading cause of cardiovascular disease and the most common noncommunicable condition seen in primary care worldwide. Without effective prevention and control, raised blood pressure significantly increases the risk of stroke, myocardial infarction, chronic kidney disease, heart failure, dementia, renal failure, and blindness. There is an urgent need for stakeholders-including individuals and families-across the health system, researchers, and decision makers to work collaboratively for improving prevention, screening and detection, diagnosis and evaluation, awareness, treatment and medication adherence, management, and control for people with or at high risk for hypertension. Meeting this need will help reduce the burden of hypertension-related disease, prevent complications, and reduce the need for hospitalization, costly interventions, and premature deaths. OBJECTIVE: This review aims to synthesize evidence on the epidemiological landscape and control of hypertension in Cameroon, and to identify elements that could potentially inform interventions to combat hypertension in this setting and elsewhere in sub-Saharan Africa. METHODS: The full search process will involve several steps, including selecting relevant databases, keywords, and Medical Subject Headings (MeSH); searching for relevant studies from the selected databases; searching OpenGrey and the Grey Literature Report for gray literature; hand searching in Google Scholar; and soliciting missed publications (if any) from relevant authors. We will select qualitative, quantitative, or mixed-methods studies with data on the epidemiology and control of hypertension in Cameroon. We will include published literature in French or English from electronic databases up to December 31, 2016, and involving adults aged 18 years or older. Both facility and population-based studies on hypertension will be included. Two reviewers of the team will independently search, screen, extract data, and assess the quality of selected studies using suitable tools. Selected studies will be analyzed by narrative synthesis, meta-analysis, or both, depending on the nature of the data retrieved in line with the review objectives. RESULTS: This review is part of an ongoing research program on disease prevention and control in the context of the dual burden of communicable and noncommunicable diseases in Africa. The first results are expected in 2017. CONCLUSIONS: This review will provide a comprehensive assessment of the burden of hypertension and control measures that have been designed and implemented in Cameroon. Findings will form the knowledge base relevant to stakeholders across the health system and researchers who are involved in hypertension prevention and control in the community and clinic settings in Cameroon, as a yardstick for similar African countries. TRIAL REGISTRATION: PROSPERO registration number: CRD42017054950; http://www.crd.york.ac.uk/PROSPERO/ display_record.asp?ID=CRD42017054950 (Archived by WebCite at http://www.webcitation.org/6qYSjt9Jc).
RESUMO
BACKGROUND: Adiponectin (APN) is an adipokine with insulin-sensitizing, anti-inflammatory, and vasculoprotective properties. Hypoadiponectinemia has been linked with disease states, such as obesity, type 2 diabetes, and cardiovascular disease. Carotid intima-media thickness (cIMT) is a strong and independent predictor of both coronary and cerebrovascular events, and has been used as a surrogate marker of subclinical atherosclerosis. The aim of this report is to systematically review the evidence on the relationship between APN and cIMT in a wide range of individuals. MATERIALS AND METHODS: Medline, Embase, Biosis, Scopus, Web of Science, and Pubmed were searched for published studies and conference abstracts. The "sign test" and "vote count" methods were used to estimate the direction and significance of the relationship between APN and cIMT. The quality of the eligible studies was evaluated using an adapted version of the New Castle Ottawa quality assessment scale. RESULTS: Fifty-five articles fulfilled the inclusion criteria, comprised of only cross-sectional studies, including healthy subjects, general population, and individuals with metabolic, inflammatory, or other chronic diseases. Most associations between APN and cIMT followed a negative direction in the healthier and general populations, and also in cohorts with metabolic disorders and other chronic diseases, but not in those with inflammatory diseases (sign test). These associations were generally found to be weak or non-significant among all cohort groups studied (vote count). CONCLUSION: Our results are suggestive but not conclusive for an inverse association between APN levels and cIMT in diseased and non-diseased populations.
Assuntos
Adiponectina/sangue , Espessura Intima-Media Carotídea , Doenças Metabólicas/metabolismo , Humanos , Doenças Metabólicas/fisiopatologia , Fatores de RiscoRESUMO
OBJECTIVE: To evaluate the association between the presence of integrated systems of stroke care and stroke case-fatality across Canada. METHODS: We used the Canadian Institute of Health Information's Discharge Abstract Database to retrospectively identify a cohort of stroke/TIA patients admitted to all acute care hospitals, excluding the province of Quebec, in 11 fiscal years from 2003/2004 to 2013/2014. We used a modified Poisson regression model to compute the adjusted incidence rate ratio (aIRR) of 30-day in-hospital mortality across time for provinces with stroke systems compared to those without, controlling for age, sex, stroke type, comorbidities, and discharge year. We conducted surveys of stroke care resources in Canadian hospitals in 2009 and 2013, and compared resources in provinces with integrated systems to those without. RESULTS: A total of 319,972 patients were hospitalized for stroke/TIA. The crude 30-day mortality rate decreased from 15.8% in 2003/2004 to 12.7% in 2012/2013 in provinces with stroke systems, while remaining 14.5% in provinces without such systems. Starting with the fiscal year 2009/2010, there was a clear reduction in relative mortality in provinces with stroke systems vs those without, sustained at aIRR of 0.85 (95% confidence interval 0.79-0.92) in the 2011/2012, 2012/2013, and 2013/2014 fiscal years. The surveys indicated that facilities in provinces with such systems were more likely to care for patients on a stroke unit, and have timely access to a stroke prevention clinic and telestroke services. CONCLUSION: In this retrospective study, the implementation of integrated systems of stroke care was associated with a population-wide reduction in mortality after stroke.
Assuntos
Prestação Integrada de Cuidados de Saúde/tendências , Mortalidade Hospitalar/tendências , Assistência ao Paciente/mortalidade , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/terapia , Idoso , Idoso de 80 Anos ou mais , Canadá/epidemiologia , Estudos de Coortes , Prestação Integrada de Cuidados de Saúde/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Assistência ao Paciente/métodos , Assistência ao Paciente/tendências , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnósticoRESUMO
BACKGROUND AND PURPOSE: Providing participants with evidence-based care for secondary prevention is an ethical and scientific priority for trials in stroke therapy. The optimal strategy, however, is uncertain. We report the performance of a new approach for delivering preventive care to trial participants. METHODS: Participants were enrolled in the Insulin Resistance Intervention after Stroke trial, which examined the insulin sensitiser, pioglitazone versus placebo for prevention of stroke and myocardial infarction after ischaemic stroke or transient ischaemic attack. Preventive care was the responsibility of the participants' personal healthcare providers, but investigators monitored care and provided feedback annually. We studied achievement of 8 prevention goals at baseline and 3 annual visits, with a focus on 3 priority goals: blood pressure <140/90â mmâ Hg, low-density lipoprotein (LDL) cholesterol <2.59â mmol/L and antithrombotic therapy. RESULTS: The proportion of participants achieving the priority goals was highest for antithrombotic use (96-99% in each year) and similar for blood pressure (66-72% in each year) and LDL (68-70% in each year). All 3 priority goals were achieved by 47-52% of participants in any given year. However, only 22% of participants achieved all 3 goals in each year. CONCLUSIONS: A strategy of monitoring care and providing feedback was associated with high average yearly achievement of 3 priority secondary prevention goals, but the majority of trial participants did not persist in being at goal over time. TRIAL REGISTRATION NUMBER: NCT00091949.