1,720,998 research outputs found
Obstructive sleep apnea and chronic kidney disease: Open questions on a potential public health problem
Full text linkEditorial, no abstrac
Blood-pressure variability in patients with obstructive sleep apnea: current perspectives
Full text linkOreste Marrone,1 Maria R Bonsignore1,2 1National Research Council of Italy, Institute of Biomedicine and Molecular Immunology, 2DiBiMIS, University of Palermo, Palermo, Italy Abstract: Obstructive sleep apnea (OSA) is often associated with hypertension and other cardiovascular diseases. Blood pressure (BP) variability is part of the assessment of cardiovascular risk. In OSA, BP variability has been studied mainly as very short-term (beat-by-beat) and short-term (24-hour BP profile) variability. BP measured on consecutive heartbeats has been demonstrated to be highly variable, due to repeated peaks during sleep, so that an accurate assessment of nocturnal BP levels in OSA may require peculiar methodologies. In 24-hour recordings, BP frequently features a “nondipping” profile, ie, <10% fall from day to night, which may increase cardiovascular risk and occurrence of major cardiovascular events in the nocturnal hours. Also, BP tends to show a large “morning BP surge”, a still controversial negative prognostic sign. Increased very short-term BP variability, high morning BP, and nondipping BP profile appear related to the severity of OSA. Treatment of OSA slightly reduces mean 24-hour BP levels and nocturnal beat-by-beat BP variability by abolishing nocturnal BP peaks. In some patients OSA treatment turns a nondipping into a dipping BP profile. Treatment of arterial hypertension in OSA usually requires both antihypertensive pharmacological therapy and treatment of apnea. Addressing BP variability could help improve the management of OSA and reduce cardiovascular risk. Possibly, drug administration at an appropriate time would ensure a dipping-BP profile. Keywords: sleep apnea, ambulatory blood-pressure monitoring, beat-by-beat measurements, blood-pressure dipping, morning blood-pressure surg
Efficacy and comfort of volume-guaranteed pressure support in patients with chronic ventilatory failure of neuromuscular origin
No full textSpectrum of sleep‐disordered breathing and quality of sleep in adolescent and adult patients with spinal muscular atrophy
No full textSleep-disordered breathing is common among children with spinal muscular atrophy, but has been hardly studied among adult subjects. Little is known about sleep quality in spinal muscular atrophy. The aims of this study were to evaluate occurrence and characteristics of sleep-disordered breathing and subjective sleep quality among adolescent and adult patients with spinal muscular atrophy type 2 or 3. Twenty patients aged 33.9 +/- 15.2 years were studied. They underwent nocturnal cardiorespiratory monitoring, lung and muscular function evaluation, and were administered the Pittsburgh Sleep Quality Index questionnaire. Nineteen patients showed sleep-disordered breathing, with obstructive events in seven subjects and non-obstructive events in the remaining 12. In the latter group, 10 patients showed pseudo-obstructive hypopneas. Patients with non-obstructive sleep-disordered breathing were younger (p = 0.042), had a lower body mass index (p = 0.0001), were more often affected by spinal muscular atrophy type 2 (p = 0.001), and showed worse impairment of respiratory function than patients with obstructive sleep-disordered breathing. Ten patients were classified as poor sleepers and 10 patients good sleepers. In the whole sample, sniff nasal inspiratory pressure proved to be the only independent predictor of sleep quality (p = 0.009). In conclusion, sleep-disordered breathing is common even among adult patients with spinal muscular atrophy type 2 and 3, and may show either obstructive or different types on non-obstructive features. A worse respiratory muscle function is associated to non-obstructive sleep-disordered breathing and poorer sleep quality. Sleep quality should receive greater attention especially in patients with spinal muscular atrophy type 2, who have a poorer respiratory muscle function, as it could affect their quality of life
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Obstructive sleep apnea and comorbidities: a dangerous liaison
Full text linkAbstract Obstructive sleep apnea (OSA) is a highly prevalent disease, and is traditionally associated with increased cardiovascular risk. The role of comorbidities in OSA patients has emerged recently, and new conditions significantly associated with OSA are increasingly reported. A high comorbidity burden worsens prognosis, but some data suggest that CPAP might be protective especially in patients with comorbidities. Aim of this narrative review is to provide an update on recent studies, with special attention to cardiovascular and cerebrovascular comorbidities, the metabolic syndrome and type 2 diabetes, asthma, COPD and cancer. Better phenotypic characterization of OSA patients, including comorbidities, will help to provide better individualized care. The unsatisfactory adherence to CPAP in patients without daytime sleepiness should prompt clinicians to examine the overall risk profile of each patient in order to identify subjects at high risk for worse prognosis and provide the optimal treatment not only for OSA, but also for comorbidities
Challenges in the identification of nocturnal respiratory events in adult patients affected by spinal muscular atrophy
No full textnot availabl
Variations on the Author
Full text link“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
Full text linkWe 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
- …
