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991.
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Background
New lipid management guidelines in the United States have created controversy regarding risk assessment using the new Pooled Cohort Equations (PCE) which might overestimate cardiovascular risk and identify an excessive number of patients as new candidates for statin therapy.Methods
We compared the Framingham Risk Score (FRS) used in Canada with PCE, the FRS version used in Adult Treatment Panel III (ATP III), Reynolds Risk Score (RRS), and Systematic Coronary Risk Evaluation (SCORE) using patient profile simulation of 10 cohorts of 100,000 each (total n = 1,000,000 for each comparison). Patients with diabetes, established cardiovascular disease, or family history of premature cardiovascular disease were not considered, mimicking uncomplicated primary prevention. Analyses were performed separately for men and women and for black individuals when feasible.Results
SCORE (high-risk version) was most concordant with FRS in men, whereas PCE was most concordant in black women. Compared with FRS, all other algorithms except SCORE (high-risk version) identified more simulations as low risk. Reclassification from low FRS to a higher risk was not seen using RRS or ATP III and seen in < 5% of simulations using PCE, affecting predominantly black subject simulations.Conclusions
Choice of risk calculator leads to systematic differences in risk categorization that can influence eligibility for lipid-lowering therapy. Compared with FRS, an isolated switch to PCE, RRS, or ATP III is unlikely to lead to substantial reclassification from low to higher risk categories in Canada. 相似文献993.
Sue Pavord Jecko Thachil Beverley J. Hunt Mike Murphy Gillian Lowe Mike Laffan Mike Makris Adrian C. Newland Drew Provan John D. Grainger Quentin A. Hill 《British journal of haematology》2020,189(6):1038-1043
This document aims to provide practical guidance for the assessment and management of patients with thrombocytopenia, with a particular focus on immune thrombocytopenia (ITP), during the COVID-19 pandemic. The intention is to support clinicians and, although recommendations have been provided, it is not a formal guideline. Nor is there sufficient evidence base to conclude that alternative approaches to treatment are incorrect. Instead, it is a consensus written by clinicians with an interest in ITP or coagulation disorders and reviewed by members of the UK ITP forum. 相似文献
994.
We report the growth of carbon dioxide (CO2) whiskers at low temperatures (−70 °C to −65 °C) and moderate pressure (4.4 to 1.0 bar). Their axial growth was assessed by optical video analysis. The identities of these whiskers were confirmed as CO2 solids by Raman spectroscopy. A vapor–solid growth mechanism was proposed based on the influence of the relative humidity on the growth.Carbon dioxide (CO2) whiskers were reported to grow at low temperatures (−70 °C to −65 °C) and moderate pressure (4.4 to 1.0 bar). 相似文献
995.
Kui Kai Lau Yuen Kwun Wong Yap Hang Chan Kay Cheong Teo Koon Ho Chan Leonard Sheung Wai Li Raymond Tak Fai Cheung Chung Wah Siu Shu Leong Ho Hung Fat Tse 《Atherosclerosis》2014
Background
Visit-to-visit blood pressure variability (BPV) is a simple surrogate marker for the development of atherosclerotic diseases, cardiovascular and all-cause mortality. Nevertheless, the relative prognostic value of BPV in comparison with other established vascular assessments remain uncertain.Methods
We prospectively followed-up 656 high-risk patients with diabetes or established cardiovascular or cerebrovascular diseases for the occurrence of major adverse cardiovascular events (MACEs). Baseline brachial endothelial function, carotid intima-media thickness (IMT) and plaque burden, ankle-brachial index and arterial stiffness were determined. Visit-to-visit BPV were recorded during a mean 18 ± 9 outpatient clinic visits.Results
After a mean 81 ± 12 month's follow-up, 123 patients (19%) developed MACEs. Patients who developed a MACE had significantly higher systolic BPV, more severe endothelial function, arterial stiffness and systemic atherosclerotic burden compared to patients who did not develop a MACE (all P < 0.01). BPV significantly correlated with all of the vascular assessments (P < 0.01). A high carotid IMT had the greatest prognostic value in predicting development of a MACE (area under receiver operating characteristic curve (AUC) 0.69 ± 0.03, P < 0.01). A high BPV also had moderate prognostic value in prediction of MACE (AUC 0.65 ± 0.03, P < 0.01). After adjustment of confounding factors, a high BPV remained a significant independent predictor of MACE (hazards ratio 1.67, 95% confidence interval 1.14-2.43, P < 0.01).Conclusions
Compared with established surrogate markers of atherosclerosis, visit-to-visit BPV provides similar prognostic information and may represent a new and simple marker for adverse outcomes in patients with vascular diseases. 相似文献996.
Sharon Goldberg Hannah Gardener Eduard Tiozzo Cheung Ying Kuen Mitchell S.V. Elkind Ralph L. Sacco Tatjana Rundek 《Atherosclerosis》2014
Background
The evidence supporting recommendations to limit intake of cholesterol rich foods is inconclusive. We aimed to examine the association between egg consumption and carotid atherosclerosis phenotypes, and the association with clinical vascular events in a prospective, urban, multi-ethnic population.Methods and results
The Northern Manhattan Study is a population based cohort to determine stroke incidence, risk factors and prognosis. A sub-cohort of 1429 NOMAS participants with both carotid ultrasounds and comprehensive dietary information was evaluated (mean ± SD age of participants 65.80 ± 8.80, 40% male, 18% white, 20% black, 60% Hispanic). The association between egg consumption and carotid intima media thickness (cIMT) was assessed with linear regression. Logistic and quantile regression was used to examine the association between egg consumption and carotid plaque presence, thickness, and area. The relation between egg consumption and clinical vascular events (N = 2669) was examined with Cox models. The mean total cIMT was 0.91 ± 0.08 mm and 58% had carotid plaque present. Increasing egg consumption was inversely associated with cIMT, plaque presence, thickness, and area, in models adjusted for demographics, vascular risk factors and diet. For every additional egg consumed per week, the risk of plaque decreased by 11% (95% CI 3%–18%). No association was detected between egg consumption and risk of clinical vascular outcomes, over a mean follow up of 11 years and after adjustment for covariates.Conclusions
Frequency of egg consumption in the low to moderate range was inversely related to several markers of carotid atherosclerosis. No association with clinical vascular events, including stroke, was detected. Our findings do not support current vascular health guidelines suggesting the extreme limitation or avoidance of egg consumption due to its cholesterol content. 相似文献997.
Michelle W. Ng Julie Angerosa Igor E. Konstantinov Michael M. Cheung Salvatore Pepe 《Clinical and experimental pharmacology & physiology》2019,46(11):995-1000
Remote ischaemic preconditioning (RIPC) has been employed as a non‐invasive protective intervention against myocardial ischaemia–reperfusion injury in animal studies. However, the underlying mechanisms are incompletely defined in humans and its clinical efficacy has been inconclusive. As advanced age, disease, and drugs may confound RIPC mechanisms in patients, our aim is to measure whether RIPC evokes release of adenosine, bradykinin, met‐enkephalin, nitric oxide, and apolipoproteins in healthy young adults. Healthy subjects (n = 18, 9 males, 23 ± 1.5 years old; 9 females, 23 ± 1.8 years old) participated after informed consent. RIPC was applied using a blood pressure cuff to the dominant arms for four cycles of 5‐minute cuff inflation (ischaemia) and 5‐minute cuff deflation (reperfusion). Blood was sampled at baseline and immediately after the final cuff deflation (Post‐RIPC). Baseline and Post‐RIPC plasma levels of adenosine, bradykinin, met‐enkephalin, apolipoprotein A‐1 (ApoA‐1), apolipoprotein D (ApoD), and nitric oxide (as nitrite) were measured via ELISA and high‐performance liquid chromatography. Mean (±SD) baseline levels of adenosine, bradykinin, met‐enkephalin, ApoA‐1, ApoD, and nitrite in healthy young adults were 13.8 ± 6.5 ng/mL, 2.6 ± 1.9 μg/mL, 594.1 ± 197.4 pg/mL, 3.0 ± 0.7 mg/mL, 22.2 ± 4.0 μg/mL, and 49.8 ± 13.4 nmol/L, respectively. Post‐RIPC adenosine and nitrite levels increased (59.5 ± 37.9%, P < .0001; 32.2 ± 19.5%, P < .0001), whereas met‐enkephalin and ApoD levels marginally decreased (5.3 ± 14.0%, P = .04; 10.8 ± 20.5%, P = .04). Post‐RIPC levels were not influenced by sex, age, blood pressure, waist circumference, or BMI. RIPC produces increased levels of adenosine and nitrites, and decreased met‐enkephalin and ApoD in the plasma of young healthy adults. 相似文献
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