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Author

John Yarnell

Other affiliations: Queen's University
Bio: John Yarnell is an academic researcher from Queen's University Belfast. The author has contributed to research in topics: Population & Risk factor. The author has an hindex of 44, co-authored 94 publications receiving 8248 citations. Previous affiliations of John Yarnell include Queen's University.


Papers
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TL;DR: It is of great importance that guidelines and recommendations are presented in formats that are easily interpreted, and their implementation programmes must also be well conducted.
Abstract: Guidelines aim to present all the relevant evidence on a particular issue in order to help physicians to weigh the benefits and risks of a particular diagnostic or therapeutic procedure. They should be helpful in everyday clinical decision-making. A great number of guidelines have been issued in recent years by different organizations-European Society of Cardiology (ESC), American Heart Association (AHA), American College of Cardiology (ACC), and other related societies. By means of links to web sites of National Societies several hundred guidelines are available. This profusion can put at stake the authority and validity of guidelines, which can only be guaranteed if they have been developed by an unquestionable decision-making process. This is one of the reasons why the ESC and others have issued recommendations for formulating and issuing guidelines. In spite of the fact that standards for issuing good quality guidelines are well defined, recent surveys of guidelines published in peer-reviewed journals between 1985 and 1998 have shown that methodological standards were not complied with in the vast majority of cases. It is therefore of great importance that guidelines and recommendations are presented in formats that are easily interpreted. Subsequently, their implementation programmes must also be well conducted. Attempts have been made to determine whether guidelines improve the quality of clinical practice and the utilization of health resources. In addition, the legal implications of medical guidelines have been discussed and examined, resulting in position documents, which have been published by a specific Task Force. The ESC Committee for Practice Guidelines (CPG) supervises and coordinates the preparation of new Guidelines and Expert Consensus Documents produced by Task Forces, expert groups or consensus panels. The Committee is also responsible for the endorsement of these guidelines or statements. The rationale for an active approach to the prevention of cardiovascular diseases (CVD) is …

2,119 citations

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TL;DR: There is an important interaction between birthweight and BMI such that the increased risk of coronary heart disease associated with low birthweight is restricted to people who have high BMI in adulthood.

509 citations

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TL;DR: The value of sex-specific GWAS to unravel the sexually dimorphic genetic underpinning of complex traits is demonstrated, with no evidence for genetic effects with opposite directions in men versus women.
Abstract: Given the anthropometric differences between men and women and previous evidence of sex-difference in genetic effects, we conducted a genome-wide search for sexually dimorphic associations with height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip-ratio (133,723 individuals) and took forward 348 SNPs into follow-up (additional 137,052 individuals) in a total of 94 studies. Seven loci displayed significant sex-difference (FDR<5%), including four previously established (near GRB14/COBLL1, LYPLAL1/SLC30A10, VEGFA, ADAMTS9) and three novel anthropometric trait loci (near MAP3K1, HSD17B4, PPARG), all of which were genome-wide significant in women (P<5×10(-8)), but not in men. Sex-differences were apparent only for waist phenotypes, not for height, weight, BMI, or hip circumference. Moreover, we found no evidence for genetic effects with opposite directions in men versus women. The PPARG locus is of specific interest due to its role in diabetes genetics and therapy. Our results demonstrate the value of sex-specific GWAS to unravel the sexually dimorphic genetic underpinning of complex traits.

402 citations

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TL;DR: The findings suggest an etiological role for CRP and IL-6 in some cancers, and further large prospective and genetic studies would help to better understand this role.
Abstract: We investigated the associations of circulating C-reactive protein (CRP) and interleukin-6 (IL-6) with cancer risk. We examined the associations of CRP and IL-6 with incident cancer in two prospective cohorts, the British Women’s Heart and Health Study (4,286 women aged 60–80) and the Caerphilly Cohort (2,398 men aged 45–59) using Cox regression and pooled our findings with previous prospective studies’ in fixed and random effects meta-analyses. CRP and IL-6 were associated with some incident cancers in our cohorts, but the numbers of cancer cases were small. In our meta-analyses elevated CRP was associated with an increased overall risk of cancer (random effects estimate (RE): 1.10, 95% CI: 1.02, 1.18) and lung cancer (RE: 1.32, 95% CI: 1.08, 1.61). Its associations with colorectal (RE: 1.09, 95% CI: 0.98, 1.21) and breast cancer risks (RE: 1.10, 95% CI: 0.97, 1.26) were weaker. CRP appeared unrelated to prostate cancer risk (RE: 1.00 0.88, 1.13). IL-6 was associated with increased lung and breast cancer risks and decreased prostate cancer risk, and was unrelated to colorectal cancer risk. Our findings suggest an etiological role for CRP and IL-6 in some cancers. Further large prospective and genetic studies would help to better understand this role.

269 citations

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TL;DR: This study provides the first evidence that the MTRR A66G polymorphism significantly influences the circulating tHcy concentration, and estimates that 66AA homozygotes have, on average, an approximately 4% increase in cardiovascular disease risk compared to 66GG homozygote.

265 citations


Cited by
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Journal ArticleDOI
TL;DR: 2007 Guidelines for the Management of Arterial Hypertension : The Task Force for the management of Arterspertension of the European Society ofhypertension (ESH) and of theEuropean Society of Cardiology (ESC).
Abstract: 2007 Guidelines for the Management of Arterial Hypertension : The Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC).

9,932 citations

Journal ArticleDOI
TL;DR: The goals of this new consensus are to provide an abbreviated document to focus on key aspects of diagnosis and management, and to update the information based on new publications and the newer guidelines, but not to add an extensive list of references.

7,099 citations

Journal ArticleDOI
TL;DR: 2007 Guidelines for the Management of Arterial Hypertension : The Task Force for the management of Arterspertension of the European Society ofhypertension (ESH) and of theEuropean Society of Cardiology (ESC).
Abstract: Because of new evidence on several diagnostic and therapeutic aspects of hypertension, the present guidelines differ in many respects from the previous ones. Some of the most important differences are listed below: 1. Epidemiological data on hypertension and BP control in Europe. 2. Strengthening of the prognostic value of home blood pressure monitoring (HBPM) and of its role for diagnosis and management of hypertension, next to ambulatory blood pressure monitoring (ABPM). 3. Update of the prognostic significance of night-time BP, white-coat hypertension and masked hypertension. 4. Re-emphasis on integration of BP, cardiovascular (CV) risk factors, asymptomatic organ damage (OD) and clinical complications for total CV risk assessment. 5. Update of the prognostic significance of asymptomatic OD, including heart, blood vessels, kidney, eye and brain. 6. Reconsideration of the risk of overweight and target body mass index (BMI) in hypertension. 7. Hypertension in young people. 8. Initiation of antihypertensive treatment. More evidence-based criteria and no drug treatment of high normal BP. 9. Target BP for treatment. More evidence-based criteria and unified target systolic blood pressure (SBP) (<140 mmHg) in both higher and lower CV risk patients. 10. Liberal approach to initial monotherapy, without any all-ranking purpose. 11. Revised schema for priorital two-drug combinations. 12. New therapeutic algorithms for achieving target BP. 13. Extended section on therapeutic strategies in special conditions. 14. Revised recommendations on treatment of hypertension in the elderly. 15. Drug treatment of octogenarians. 16. Special attention to resistant hypertension and new treatment approaches. 17. Increased attention to OD-guided therapy. 18. New approaches to chronic management of hypertensive disease

7,018 citations

Journal ArticleDOI
TL;DR: The purpose of the present report is to update and clarify the 1995 recommendations on the types and amounts of physical activity needed by healthy adults to improve and maintain health.
Abstract: Summary—In 1995 the American College of Sports Medicine and the Centers for Disease Control and Prevention published national guidelines on Physical Activity and Public Health The Committee on Exercise and Cardiac Rehabilitation of the American Heart Association endorsed and supported these recommendations The purpose of the present report is to update and clarify the 1995 recommendations on the types and amounts of physical activity needed by healthy adults to improve and maintain health Development of this document was by an expert panel of scientists, including physicians, epidemiologists, exercise scientists, and public health specialists This panel reviewed advances in pertinent physiologic, epidemiologic, and clinical scientific data, including primary research articles and reviews published since the original recommendation was issued in 1995 Issues considered by the panel included new scientific evidence relating physical activity to health, physical activity recommendations by various organizations in the interim, and communications issues Key points related to updating the physical activity recommendation were outlined and writing groups were formed A draft manuscript was prepared and circulated for review to the expert panel as well as to outside experts Comments were integrated into the final recommendation Primary Recommendation—To promote and maintain health, all healthy adults aged 18 to 65 yr need moderate-intensity aerobic (endurance) physical activity for a minimum of 30 min on five days each week or vigorous-intensity aerobic physical activity for a minimum of 20 min on three days each week [I (A)] Combinations of moderate- and vigorous-intensity activity can be performed to meet this recommendation [IIa (B)] For example, a person can meet the recommendation by walking briskly for 30 min twice during the week and then jogging for 20 min on two other days Moderate-intensity aerobic activity, which is generally equivalent to a brisk walk and noticeably accelerates the heart rate, can be accumulated toward the 30-min minimum by performing bouts each lasting 10 or more minutes [I (B)] Vigorous-intensity activity is exemplified by jogging, and causes rapid breathing and a substantial increase in heart rate In addition, every adult should perform activities that maintain or increase muscular strength and endurance a minimum of two days each week [IIa (A)] Because of the dose-response relation between physical activity and health, persons who wish to further improve their personal fitness, reduce their risk for chronic diseases and disabilities or prevent unhealthy weight gain may benefit by exceeding the minimum recommended amounts of physical activity [I (A)] (Circulation 2007;116:1081-1093)

6,863 citations

Journal ArticleDOI
TL;DR: A sex-specific multivariable risk factor algorithm can be conveniently used to assess general CVD risk and risk of individual CVD events (coronary, cerebrovascular, and peripheral arterial disease and heart failure) and can be used to quantify risk and to guide preventive care.
Abstract: Background—Separate multivariable risk algorithms are commonly used to assess risk of specific atherosclerotic cardiovascular disease (CVD) events, ie, coronary heart disease, cerebrovascular disease, peripheral vascular disease, and heart failure. The present report presents a single multivariable risk function that predicts risk of developing all CVD and of its constituents. Methods and Results—We used Cox proportional-hazards regression to evaluate the risk of developing a first CVD event in 8491 Framingham study participants (mean age, 49 years; 4522 women) who attended a routine examination between 30 and 74 years of age and were free of CVD. Sex-specific multivariable risk functions (“general CVD” algorithms) were derived that incorporated age, total and high-density lipoprotein cholesterol, systolic blood pressure, treatment for hypertension, smoking, and diabetes status. We assessed the performance of the general CVD algorithms for predicting individual CVD events (coronary heart disease, stroke, peripheral artery disease, or heart failure). Over 12 years of follow-up, 1174 participants (456 women) developed a first CVD event. All traditional risk factors evaluated predicted CVD risk (multivariable-adjusted P0.0001). The general CVD algorithm demonstrated good discrimination (C statistic, 0.763 [men] and 0.793 [women]) and calibration. Simple adjustments to the general CVD risk algorithms allowed estimation of the risks of each CVD component. Two simple risk scores are presented, 1 based on all traditional risk factors and the other based on non–laboratory-based predictors. Conclusions—A sex-specific multivariable risk factor algorithm can be conveniently used to assess general CVD risk and risk of individual CVD events (coronary, cerebrovascular, and peripheral arterial disease and heart failure). The estimated absolute CVD event rates can be used to quantify risk and to guide preventive care. (Circulation. 2008;117: 743-753.)

5,959 citations