Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

As Girth Grows, Risk of Sudden Cardiac Death Shrinks

17.03.2010
Study Reaffirms ¡°Obesity Paradox¡±: Obese patients at lower risk of sudden cardiac death compared to non-obese patients

Obesity has long been identified as a risk factor for cardiovascular disease and heart failure. But, a new study conducted by researchers at the University of Rochester Medical Center found that being skinny confers no advantage when it comes to the risk of dying suddenly from cardiac causes.

Scientists found that non-obese heart failure patients ¨C including overweight, normal and underweight patients ¨C had a 76 percent increase in risk of sudden cardiac death compared to obese heart failure patients. Normal and underweight patients showed a startling 99 percent increase in risk for sudden cardiac death compared to obese patients.

The results were presented today at the American College of Cardiology Annual Scientific Session in Atlanta. The study, by researchers from one of the world¡¯s leading groups on sudden cardiac death, is the first to assess the relation between BMI and the risk of sudden cardiac death.

¡°This study is important because it not only answers questions regarding the risk of sudden cardiac death in different types of heart failure patients, but poses several new questions that need to be explored,¡± said corresponding study author Ilan Goldenberg, M.D., research associate professor of Medicine in the Cardiology Division. ¡°Why do obese heart failure patients see a risk advantage? Why do normal weight patients have a significantly different risk profile than those who are slightly overweight? These are important questions that may have treatment implications in the future.¡±

The researchers at the University¡¯s Heart Research Follow-Up Program examined the risk of sudden cardiac death in 1,231 patients who had suffered at least one prior heart attack and had been diagnosed with a low ejection fraction, a measurement of how much blood is pumped from the heart with each beat. Their analysis found that decreased BMI or body mass index was associated with a large increase in the risk of sudden cardiac death. These findings highlight the ¡°obesity paradox,¡± a phenomenon long recognized by cardiologists that, once afflicted, obese heart failure patients fare better than their slimmer counterparts. This study adds to a growing body of conflicting data regarding the relation of BMI to outcome in patients with heart failure.

¡°When we started this study we were hoping the data would disprove the obesity paradox,¡± said Bonnie Choy, co-lead author and a second year medical student at the University¡¯s School of Medicine and Dentistry. ¡°Our study is the first to create and analyze subcategories within non-obese patients, looking at overweight, normal and underweight patients, but even with this advanced analysis we still the saw an inverse relationship between BMI and sudden cardiac death.¡±

The science behind the obesity paradox in the heart failure population is unresolved, but some researchers believe timing may have something to do with it. One possible explanation is that the long-term negative effects of conventional risk factors, such as increased BMI, may be overwhelmed by the short-term effects of other factors on heart failure mortality. In addition, survival advantages that exist in obese patients with heart failure may, in the short term, outweigh the harmful effects of increased BMI.

¡°Obese patients are hard on their bodies; many don¡¯t eat right, don¡¯t exercise, and many smoke,¡± explained Eric Hansen, co-lead author and also a second year medical student at the University of Rochester. ¡°If their bodies are surviving this bad treatment then perhaps they are better equipped, from a genetic standpoint, to live with heart failure.¡±

Compared to the overweight, normal and underweight patients, obese patients were younger, had a higher ejection fraction, higher blood pressure, diabetes and were more likely to be smokers. BMI was calculated as weight in kilograms divided by the square of height in meters for all study participants. The clinical definition of obesity ¨C BMI ¡Ý30 kg/m2 ¨C was used. Overweight patients fell into the 25 to 29 kg/m2 range of BMI values and normal/underweight patients fell into the

In addition to evaluating the relationship between BMI and sudden cardiac death, researchers assessed the effect of BMI on the benefit of implantable cardioverter defibrillator (ICD) therapy. An implantable cardioverter defibrillator is a medical device about the size of a pager that is surgically implanted in the chest under local anesthesia. The device detects irregular and potentially fatal heart rhythms (arrhythmias), which often lead to sudden cardiac death, and shocks the heart back into a normal rhythm. Researchers found that implantable cardioverter defibrillator therapy was more effective in the non-obese patients with lower BMI values who were at higher risk for sudden cardiac death. These findings may help identify patients who would get the most benefit from an ICD ¨C patients with a lower BMI.

Sudden cardiac death claims up to 330,000 American lives every year, accounting for about half of all cardiac deaths. Sudden cardiac arrest, a condition in which the heart suddenly and unexpectedly stops beating, leads to sudden cardiac death if it is not treated within minutes. Most cases of sudden cardiac arrest are due to abnormal heart rhythms that can result from blockage of coronary arteries or scarring from a prior heart attack. Certain drugs can also trigger abnormal rhythms and death.

In addition to Goldenberg, Choy and Hansen worked closely with Cardiology faculty members Arthur J. Moss, M.D., and Wojciech Zareba, M.D., Ph.D., to complete this study.

For Media Inquiries:
Emily Butler
585-273-1757
Email Emily Butler

Emily Butler | EurekAlert!
Further information:
http://www.urmc.rochester.edu

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>