(Press-News.org) Average C-reactive protein (CRP) values vary in diverse populations — possibly impacting how doctors estimate cardiovascular risk and determine statin treatment, according to a new study in Circulation: Cardiovascular Genetics, a journal of the American Heart Association.
CRP is a marker of inflammation, and high levels of it in the blood have been associated with a higher risk for heart disease. But it's uncertain if the association is causal. Statins are a class of cholesterol-lowering drugs that reduce heart risk and CRP. Researchers aren't certain if CRP-lowering contributes to the health benefits of statins.
"CRP may be used at the discretion of the physician as part of a global coronary risk assessment in adults without known cardiovascular disease," according to consensus statements from the American Heart Association and Centers for Disease Control. A CRP value above a cut-point of 3mg/L indicates high risk.
In the recent Justification for the Use of Statins in Primary Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER), researchers evaluated the efficacy of statins using a risk cut-point for CRP at values more than 2mg/L. Based on JUPITER's findings, the U.S. Food and Drug Administration recently licensed the use of rosuvastatin to prevent cardiovascular disease in men over 50 years and women over 60 years who have one other risk factor and CRP greater than 2mg/L.
"The difference in average population CRP values in populations of different ancestry are sufficiently large as to have bearing on clinical management and statin eligibility based on single CRP cut-point values," said Tina Shah, Ph.D., co- author of the study and a post-doctoral research fellow at University College London.
Researchers conducted a systematic review and meta-analysis of data on 221, 287 people from 89 published studies and discovered that CRP levels differed by ethnicity, even after adjustments for age and body mass index. African- Americans had the highest CRP levels with an average of 2.6 mg/L, followed by Hispanics (2.51 mg/L), South Asians (2.34 mg/L) and Caucasians (2.03 mg/L). East Asians had the lowest CRP levels of 1.01 mg/L.
The rank order remained the same when researchers calculated the probability that people in each ethnic group would exceed the 2 mg/L CRP threshold at any age. More than half of African-Americans and Hispanics would likely exceed the 2 mg/L CRP threshold at 50 years, while less than half of East Asians would surpass the threshold. Likewise, at 60 years, less than 40 percent of East Asians and almost two-thirds of African-Americans and Hispanics would likely have a CRP > 2mg/L.
A genetic analysis in the multi-ethnic Wandsworth Heart and Stroke Study showed that a gene associated with CRP levels varied in frequency by ethnicity. This study was a population-based survey in South London to estimate the prevalence of major heart and stroke risk factors in people of different ethnic backgrounds. An assessment of lifestyle factors showed that body mass index, systolic blood pressure and smoking contributed to differences in CRP between groups, but the majority of the difference in CRP was unexplained.
"There is ongoing debate over the ability of CRP to predict the risk of heart disease over established cardiovascular risk factors, even in individuals of European origin where there is the most evidence pertaining to the CRP-coronary disease association," said Aroon D. Hingorani, Ph.D., co-author of the study and professor of genetic epidemiology and British Heart Foundation Senior Research Fellow at University College London.
"If clinicians still want to use CRP as part of heart risk prediction, the results of the current study suggest they should bear ethnicity in mind in interpreting a CRP value."
The absolute risk of heart disease for different ethnic groups and individuals should be based on established risk factors using the Framingham risk equation, she said.
###
Other co-authors are: Paul Newcombe, Ph.D.; Liam Smeeth, Ph.D.; Juliet Addo, Ph.D.; Juan P. Casas, M.D., Ph.D.; John Whittaker, Ph.D.; Michelle A. Miller, Ph.D.; Lorna Tinworth, Ph.D.; Steve Jeffery, Ph.D.; Pasquale Strazzullo, M.D.; and Francesco P. Cappuccio, M.D.
Author disclosures and funding sources are on the manuscript.
Statements and conclusions of study authors published in American Heart Association scientific journals are solely those of the study authors and do not necessarily reflect the association's policy or position. The association makes no representation or guarantee as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and device corporations are available at www.americanheart.org/corporatefunding.
Stay up to date on the latest news from American Heart Association scientific meetings, including Scientific Sessions 2010, by following us at www.twitter.com/heartnews. We will be tweeting from the conference using hashtag #AHA10News.
Additional resources:
Downloadable stock footage, animation, and our image gallery are located at www.heart.org/news under Multimedia.
END
DURHAM, N.C. – The yellow monkeyflower, an unassuming little plant that lives as both a perennial on the foggy coasts of the Pacific Northwest and a dry-land annual hundreds of miles inland, harbors a significant clue about evolution.
Duke graduate student and native northern Californian David Lowry had become interested in how a single species could live such different lifestyles. He set out to find a gene or genes that would account for the monkeyflower (Mimulus guttatus) being a lush, moisture-loving, salt-tolerant perennial on the coast, but a shorter, faster-flowering, ...
Healthy people who caught swine flu during the 2009 pandemic may have been protected against developing radiographically (x-ray) confirmed pneumonia by taking the antiviral drug oseltamivir (Tamiflu), concludes a study of cases in China published on bmj.com today.
The researchers also show that oseltamivir treatment was associated with shorter duration of fever and viral RNA shedding (the period when a virus is contagious), although they stress that their findings should be interpreted with caution.
In 2009, pandemic influenza A (H1N1) virus spread rapidly, resulting ...
DETROIT – The old saying, "never put anything smaller than your elbow in your ear," couldn't be truer for a patient who experienced vertigo and severe hearing loss after a cotton swab perforated her eardrum and damaged her inner ear.
But what makes this patient's case unique is that otolaryngologists at Henry Ford Hospital in Detroit were not only able to alleviate her vertigo with surgery, but restore her hearing – an extremely rare occurrence.
"This case is rare because the goal of surgery is not to recover hearing, but to improve vertigo," says case report lead ...
Playing white noise in class can help inattentive children learn. Researchers writing in BioMed Central's open access journal Behavioral and Brain Functions tested the effect of the meaningless random noise on a group of 51 schoolchildren, finding that although it hindered the ability of those who normally pay attention, it improved the memory of those that had difficulties in paying attention.
Göran Söderlund from Stockholm University, Sweden, worked with a team of researchers to carry out the experiments at a secondary school in Norway. He said, "There was significant ...
Intrauterine devices, originally developed as contraceptives, can also be used to treat and cure cancer of the endometrium according to new research published online in the cancer journal, Annals of Oncology [1] today (Wednesday 29 September). The finding opens the way for young women with the disease, which affects the lining of the womb, to be treated without the need for a hysterectomy, thus preserving their fertility until they have had all the children they want.
Endometrial cancer is the sixth most common cancer in women worldwide. In 2008 there were an estimated ...
In mice, early weaning and separation from their mothers promotes long-lasting hyperactivity and anxiety . Researchers writing in the open access journal BMC Neuroscience describe the development of this new behavioral model, which they hope to use to investigate the long-term effects of early childhood neglect in people.
Arthur Simen and a team of researchers from Yale University School of Medicine, USA, tested their 'Maternal separation with early weaning' (MSEW) model in a group of 80 male mice. He said, "Childhood adversity, in the form of abuse and neglect, is prevalent ...
The protein could provide a target to develop new treatments for the disease or enable earlier diagnosis, say the researchers from Barts and The London School of Medicine and Dentistry. Pancreatic cancer has the lowest survival rate of all cancers due to its lack of symptoms in the early stages, late diagnosis and its resistance to chemotherapy and radiation therapy.
The research – funded by the Pancreatic Cancer Research Fund – found that nearly three quarters of pancreatic cancer tumours had high levels of a protein known as P110γ. In laboratory experiments, when ...
BOSTON, Mass. (September 29, 2010) — Crowdsourcing, the act of contracting out problems to large groups rather than tapping individual experts, has solved puzzles in fields such as marketing, engineering and computer software. But can the wisdom of crowds help cure disease?
A large, multidisciplinary panel has recently selected 12 pioneering ideas for attacking Type 1 Diabetes, ideas selected through a crowdsourcing experiment called the Challenge in which all members of the Harvard community, as well as members of the general public, were invited to answer the question: ...
A global analysis of extinction risk for the world's plants, conducted by the Royal Botanic Gardens, Kew together with the Natural History Museum, London and the International Union for the Conservation of Nature (IUCN), has revealed that the world's plants are as threatened as mammals, with one in five of the world's plant species threatened with extinction. The study is a major baseline for plant conservation and is the first time that the true extent of the threat to the world's estimated 380,000 plant species is known, announced as governments are to meet in Nagoya, ...
In the last decade, researchers have found evidence that experiences can alter the form and structure of DNA, an effect known as epigenetics. Because these changes affect genes, events early in life have the potential to make a lasting impact on behavior and health. Recent studies focused on cancer and obesity have already shown the power of epigenetics.
In a study led by Tie-Yuan Zhang, PhD, of McGill University, researchers investigated whether these changes might apply to the activity of genes in brain regions that control neural function and mental health. The authors ...
