14 research outputs found

    Microaneurysm detection in retinal images using an ensemble classifier

    Get PDF

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

    Get PDF
    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Automated static perimetry and dimensional characteristics of the intra- and peri-papillary retinal features in myopia

    No full text
    SIGLEAvailable from British Library Document Supply Centre- DSC:DX182559 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

    Sex differences in the relationship between inflammatory and hemostatic biomarkers and metabolic syndrome: British 1958 Birth Cohort

    No full text
    &lt;p&gt;&lt;b&gt;Background:&lt;/b&gt; Circulating levels of C-reactive protein (CRP), fibrinogen, fibrin D-dimer, tissue plasminogen activator antigen (t-PA) and von Willebrand factor (VWF) are associated with incident coronary heart disease (CHD). However, their associations with metabolic syndrome and its components in large populations of men and women have not been well defined.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Objectives:&lt;/b&gt; We compare the sex associations of these biomarkers with established CHD risk factors, metabolic syndrome and its components in a large cohort.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Patients and Methods:&lt;/b&gt; 8302 men and women aged 45 years from the British 1958 birth cohort provided a blood sample. Analyses were restricted to 3457 men and 3464 women with complete data on all risk factors and no history of cardiovascular disease. Multiple regression analyses adjusted for smoking, social class, alcohol consumption and variables related to biomarker measurement error.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Results:&lt;/b&gt; Adjusted sex differences in levels of all biomarkers (except VWF) varied according to presence/absence of metabolic syndrome, its components and obesity (BMI =30 kg m-2). Associations in women were up to twice as strong for CRP, fibrinogen and t-PA with markers of obesity (body mass index, waist circumference), blood pressure, blood lipids and metabolic syndrome. D-dimer showed weaker associations and less heterogeneity by sex. There was no evidence of sex interaction in associations with VWF.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Conclusions:&lt;/b&gt; Associations between CRP, fibrinogen and t-PA and metabolic syndrome and its components were stronger in women than in men. Understanding the reasons for these differences across sex will be important in understanding the pathophysiology of cardiovascular and metabolic disease in men and women.&lt;/p&gt

    Quantification of blood vessel calibre in retinal images of multi-ethnic school children using a model based approach

    No full text
    Changes and variation in retinal vessel width are related to vascular risk factors and prospectively related to cardiovascular disease in later life. Hence, assessment of vessel width may be a useful physio-marker and potential predictor of cardiovascular status. However, measurement of vessel calibre from retinal images is a challenging process to automate. This paper proposes an automated system to measure vessel calibre in retinal images, which is demonstrated in images of multi-ethnic school children. The diameter measurement is based on the detection of the centreline pixels from a vessel probability map image, determining the vessel orientation at these pixels, extracting the vessel segments and later using a two-dimensional model, which is optimized to fit various types of intensity profiles of vessel segments. The width is then estimated from parameters of the optimized model. The method is also quantitatively analyzed using monochromatic representations of different colour spaces. The algorithm is evaluated on a recently introduced public database CHASE_DB1, which is a subset of retinal images of multi-ethnic children from the Child Heart and Health Study in England (CHASE) dataset. Moreover, the precise estimation of retinal vascular widths is critical for epidemiologists to identify the risk factors. This work also introduces an interactive software tool for epidemiologists, with which retinal vessel calibre can be precisely marked

    Blood vessel segmentation methodologies in retinal images - A survey

    No full text
    Retinal vessel segmentation algorithms are a fundamental component of automatic retinal disease screening systems. This work examines the blood vessel segmentation methodologies in two dimensional retinal images acquired from a fundus camera and a survey of techniques is presented. The aim of this paper is to review, analyze and categorize the retinal vessel extraction algorithms, techniques and methodologies, giving a brief description, highlighting the key points and the performance measures. We intend to give the reader a framework for the existing research; to introduce the range of retinal vessel segmentation algorithms; to discuss the current trends and future directions and summarize the open problems. The performance of algorithms is compared and analyzed on two publicly available databases (DRIVE and STARE) of retinal images using a number of measures which include accuracy, true positive rate, false positive rate, sensitivity, specificity and area under receiver operating characteristic (ROC) curve

    Chronic exposure to outdoor air pollution and lung function in adults

    No full text
    Background: The extent to which chronic exposure to outdoor air pollutants influences lung function in adults is unclear. The aim of this study was to measure the association between chronic exposure to outdoor air pollutants and adult lung function. Methods: The relationship between measures of lung function (forced expiratory volume in 1 s (FEV1_1) and FEV1_1 as a percentage of forced vital capacity (FVC) and average exposure to particulate matter <10 ÎŒm in diameter, nitrogen dioxide, sulfur dioxide and ozone was examined in four representative cross-sectional surveys of the English population aged â©Ÿ16 in 1995, 1996, 1997 and 2001. Year-specific estimates were pooled using fixed effects meta-analysis. Results: Greater exposure to particulate matter <10 ÎŒm in diameter, nitrogen dioxide and sulfur dioxide was associated with lower adult FEV1_1. The size of the effect on population mean FEV1_1 was about 3% for particulate matter <10 ÎŒm, and 0.7% for nitrogen dioxide and sulfur dioxide, for a 10 ÎŒg/m3 increase in pollutant concentration. The effects were most marked in men, older adults and ex-smokers. FEV1 was not associated with ozone concentration. No associations were found between the pollutants and FEV1_1 as a percentage of FVC. Conclusions: Chronic exposure to outdoor air pollution is associated with modestly reduced FEV1_1 in adults
    corecore