Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Women Can Gauge What Their Fitness Level Should be at a Given Age to Reduce Risk of Death

04.08.2005


Research reported in this week’s New England Journal of Medicine for the first time looks at the role of exercise capacity in predicting a woman’s risk of mortality

Researchers have developed a nomogram (alignment chart) specifically for women that can be used to predict their expected exercise capacity at any given age, as well as demonstrated that the resulting measure is a predictor of the risk of death. Women whose exercise capacity was less than 85 percent the age-predicted value had twice the risk of death compared to women reaching at least 85 percent, according to research led by Martha Gulati, MD, a cardiologist at the Bluhm Cardiovascular Institute of Northwestern Memorial Hospital, which will be published in the August 4 issue of the New England Journal of Medicine.

“This is the first study of its kind in women,” said Dr. Gulati. “Despite extensive research on the role of exercise stress testing and exercise capacity, there has been a lack of data on what is normal or expected for healthy women. Until now, they have been evaluated using the men’s nomogram, which does not provide an accurate assessment for women.” Exercise capacity can be estimated by performing a symptom-limited stress test based on the speed and grade of the treadmill. It is defined as the maximal oxygen uptake for a given workload and can be expressed in metabolic equivalents (MET). MET is the amount of oxygen used by an average seated person and increases with the intensity of exercise.



To utilize the nomogram to establish the percentage of predicted exercise capacity for age requires only the woman’s age and exercise capacity achieved in MET on the exercise stress test. Drawing a straight line between the age and exercise capacity will allow the determination of the percentage of predicted exercise capacity for age; a value of 100 percent is the mean for any given age. Any result greater than 100 percent indicates better-than-average performance. Any result lower than 100 percent indicates some degree of functional impairment for age.

Use of the women’s nomogram provides a more accurate assessment of prognosis among women than does use of the men’s nomogram. “Use of the male nomogram to assess women results in a lower sensitivity, translating into more false positives,” said Dr. Gulati. “That means a woman might be told she’s at a higher risk for death when, in fact, she’s not.” The sensitivity and specificity of the survival model for predicting death from any cause among the asymptomatic women are 70 percent and 47 percent, respectively, when the women’s nomogram is used. In contrast, the sensitivity and specificity are 55 and 64 percent, respectively, when the men’s nomogram is used.

“As age increases, so does the difference in predicted exercise capacity between men and women,” explains Dr. Gulati. “Use of the men’s nomogram in this study group would have resulted in 800 more false positive results,” adds Dr. Gulati. For this study, 5,721 asymptomatic women and 4,471 symptomatic women underwent a symptom-limited treadmill test according to the Bruce protocol, the most commonly performed stress test. The nomogram was then used to determine the percentage of predicted exercise capacity for both cohorts. Survival data were obtained and a survival analysis was used to estimate the rates of death from any cause and cardiac causes in each group.

The relationship between exercise capacity and the risk of death from cardiac cause was remarkably similar for all age groups in the symptomatic cohort, with two exceptions. The youngest (less than 55 years of age) and oldest women (older than 70 years) with a poor exercise capacity had an especially high mortality rate.

About Northwestern Memorial Hospital

Northwestern Memorial Hospital is one of the country’s premier academic medical centers and is the primary teaching hospital of Northwestern University’s Feinberg School of Medicine. Northwestern Memorial and its Prentice Women’s Hospital and Stone Institute of Psychiatry have 744 beds and more than 1,200 affiliated physicians and 5,000 employees. Providing state-of-the-art care, Northwestern Memorial is recognized for its outstanding clinical and surgical advancements in such areas as cardiothoracic and vascular care, gastroenterology, neurology and neurosurgery, oncology, organ and bone marrow transplantation, and women’s health.

Northwestern Memorial received the prestigious 2005 National Quality Health Care Award and is listed in eight specialties in this year’s US News & World Report’s issue of “America’s Best Hospitals.” The hospital is also cited as one of the “100 Best Companies for Working Mothers” by Working Mother magazine for the past 5 years and has been chosen by Chicagoans for a decade as their “most preferred hospital” in National Research Corporation’s annual survey.

About the Bluhm Cardiovascular Institute

The Bluhm Cardiovascular Institute at Northwestern Memorial Hospital is a world-class heart program offering comprehensive services and state-of-the-art surgical treatments in all areas of cardiovascular care. Recently named by Solucient, an industry-leading healthcare information provider, as the only Chicago hospital on its list of the country’s 100 Top Cardiovascular Hospitals, Northwestern Memorial Hospital offers a timely response to referrals and a multidisciplinary approach that joins physicians, nurses and a range of other medical specialists and caregivers from Cardiology, Cardiac Surgery, Vascular Surgery, Cardiovascular Anesthesiology and Radiology from evaluation to follow-up. Patients benefit from the latest minimally invasive surgical techniques and are offered the opportunity to participate in a range of clinical research trials.

Advanced Cardiovascular Care

Patients referred to the Bluhm Cardiovascular Institute experience a healthcare environment in which the most advanced diagnostic and treatment options are supported by state-of-the-art technology and a commitment to medical excellence through research. Expertise is available in all areas of cardiovascular care, including:

Cardiac Surgery

  • Valve repair and replacement
  • MAZE and atrial fibrillation ablation procedures
  • Coronary artery bypass with arterial conduits
  • LV and aortic aneurysm repair
  • Congestive heart failure surgery
  • Ventricular assist devices
  • Heart transplantation

Vascular Surgery

  • Thoracic and abdominal aortic aneurysm surgery
  • Carotid endarterectomy and stents
  • Endovascular surgery for aortic aneurysms and limb salvage
  • Lower extremity bypass procedures
  • Uncommon mesenteric and upper extremity revascularization
  • Supraaortic trunk revascularization

Cardiology

  • Primary and secondary prevention
  • Advanced diagnostic testing including echocardiography, nuclear cardiology, cardiac MRI and computed tomography
  • Cardiac electrophysiology, including diagnostic EP procedures, catheter ablation and pacemaker and ICD implantation
  • Heart failure management
  • Evaluation of heart valve disease
  • Acute coronary care
  • Diagnostic catheterization and interventional cardiology

Patty Keiler | CS - Presscenter
Further information:
http://www.csmc.edu/

More articles from Health and Medicine:

nachricht One gene closer to regenerative therapy for muscular disorders
01.06.2017 | Cincinnati Children's Hospital Medical Center

nachricht The gut microbiota plays a key role in treatment with classic diabetes medication
01.06.2017 | University of Gothenburg

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

A new technique isolates neuronal activity during memory consolidation

22.06.2017 | Life Sciences

Plant inspiration could lead to flexible electronics

22.06.2017 | Materials Sciences

A rhodium-based catalyst for making organosilicon using less precious metal

22.06.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>