1,721,039 research outputs found
Blood pressure response to standing is a strong determinant of masked hypertension in young to middle-age individuals
Reproducibility of daytime hypertension, night-time hypertension, and nocturnal blood pressure dipping patterns in young to middle age patients with stage 1 hypertension
Objective: To investigate the reproducibility of ambulatory BP sub-periods and nocturnal dipping phenotypes assessed twice 3 months apart in young-to-middle-age untreated individuals screened for stage 1 hypertension. Design and methods: We investigated 1096, 18-to-45-year old participants from the HARVEST. Their office BP was 145.8 ± 10.4/93.7 ± 5.7 mmHg. Office BP and 24 h BP were measured at baseline and after 3 months. Office, 24-h, daytime and night-time hypertensions, and nocturnal dipping patterns were defined according to the 2023 ESH guidelines. Between-recording agreement was evaluated with kappa statistics. Results: Reproducibility evaluated with weighted kappa was moderate for both 24 h hypertension (K = 0.48) and daytime hypertension (K = 0.50) and was only fair for night-time hypertension (K = 0.36). Between-measurement agreement was even worse for isolated night-time hypertension (K = 0.24), and was poor for office hypertension (K = 0.14). The better reproducibility of daytime than night-time period was confirmed by the analysis of BP as continuous variable (all between-period differences, P < 0.001). Nondipping was present in 31.8%, and showed a fair agreement (K = 0.28,). Poorer agreement was shown by extreme dipping (K = 0.18) and reverse dipping (K = 0.07). Conclusions: These data show that within the ambulatory sub-periods, daytime hypertension has a better reproducibility than night-time hypertension. This suggests that the better association with adverse outcomes shown by sleep BP compared to wake BP in observational studies is not due to a better reproducibility of the former. The between-measurement agreement is even worse for isolated nocturnal hypertension and dipping patterns, especially for extreme and reverse dipping. Thus, these BP phenotypes should be confirmed with repeat ambulatory BP monitoring
Dipping pattern and short-term blood pressure variability are stronger predictors of cardiovascular events than average 24-hour blood pressure in young hypertensive subjects
Aims The role of increased blood pressure (BP) variability and a blunted day-night BP drop is still being debated, particularly in young hypertensive subjects. We investigated the contribution of BP variability and day-night BP changes combined to cardiovascular events in initially untreated young hypertensive individuals. Methods and results We selected 1794 subjects aged <= 45 years from the HARVEST and the PIUMA studies, two long-term observational studies in subjects with hypertension. The outcome was a composite pool of non-fatal myocardial infarction or stroke, heart failure needing hospitalization, death from cardiovascular causes, and myocardial or limb revascularization procedures. During an 11.3-year follow-up, 140 cardiovascular events were accrued. A multivariable Cox model which included BP variability and non-dipping was more informative (Akaike Information Criterion = 1536.9) than the model which included average of 24-h BP (Akaike Information Criterion = 1553.6). A higher hazard ratio (HR) was observed for non-dipping [HR 2.22; 95% confidence interval (CI): 1.55-3.17; P < 0.0001] and for high BP variability (HR 1.84; 95% CI: 1.26-2.65; P = 0.0015) than for high average 24-h BP (HR 1.58; 95% CI: 1.07-2.33; P = 0.020). When average 24-h ambulatory BP was included in a nested model, the -2log likelihood decreased from 1524.9 to 1519.3, and there was a tendency for an interactive effect between 24-h BP and non-dipping on risk of cardiovascular events (P = 0.092). Conclusion In young hypertensive individuals, prognostic models including BP variability and non-dipping pattern provide better information than models with average 24-h ambulatory BP alone. More consideration should be given to BP variability and the day-night BP pattern beyond the average 24-h ambulatory BP in young hypertensive subjects
White coat hypertension as predictor of long-lasting blood pressure decline in stage 1 hypertension
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Can apical ballooning cardiomyopathy and anterior STEMI be differentiated based on β1 and β2-adrenergic receptors polymorphisms?
Catecholamine excess along with an exaggerated sympathetic stimulation appears to play a major role in the pathophysiological mechanism of tako-tsubo cardiomyopathy (TTC), which mimics acute ST-elevation myocardial infarction (STEMI). The aim of the present study was to investigate differences in the distribution of allelic variants of β1- and β2-adrenoceptors between TTC and anterior STEMI patients compared to normal subjects
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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