["Heart Rate Variability, or HRV, is under-appreciated measure of heart health...]

Greater Heart Rate Variability

The term called “heart rate variability” means that minute-by-minute (or even second-by-second) your heart rate fluctuates depending on internal and external stimulus. If your resting heart rate is 60 beats per minute, it makes sense that your heart would beat 600 times in 10 minutes. While that translates to one beat per second on average, in reality, it may be that over a 10-second time period, there are five beats in three seconds and then five beats in the next seven second. When we are young and/or more physically fit, we have greater heart rate variability, which means that our cardiovascular system is responding to various stimuli and is being appropriately controlled by several different neurological factors. As you age, there is a decline in the plasticity of the heart to react moment by moment to any changes in the need for blood flow and oxygen to the rest of the body; physical inactivity has a similar effect. Therefore, sedentary individuals and older adults usually have low heart rate variability. Low heart rate variability is associated with greater risk for cardiovascular events.

A team of scientists in France set out to evaluate the impact that long-term exercise has on heart rate variability in a group of older adults (average age 75 years). The results showed that those individuals who regularly participated in sport activity expended more energy each week, spent more time per week doing intense activities, and had lower resting heart rates. These findings were expected. What was new in this research was that heart rate variability was higher in the older individuals who exercised regularly when compared to older individuals who were sedentary.

The take home message: once again, research demonstrates that older individuals who exercise regularly have hearts that behave more like younger people. There is some evidence that as little as one week of aerobic exercise training in older adults can improve heart rate variability. This quick response of the heart to adapt may reduce the risk of cardiovascular events very quickly.

Being young at heart literally can happen at any age. Having a responsive heart that can vary when needed is one more reason to exercise regularly.

(Reference: Bouchheit and colleagues. Heart Rate Variability in Sportive Elderly: Relationship with Daily Activity. Medicine and Science in Sports and Exercise. Volume 36(4):601-605, 2004.)

By Courtney Rubin
November 26, 2010

The gentle, 2,000-year-old Chinese practice of tai chi is often described as “meditation in motion.” But the Harvard Women’s Health Watch newsletter suggests a more apt description is “medication in motion.”

Tai chi, the most famous branch of Qigong, or exercises that harness the qi (life energy, pronounced “chee”), has been linked to health benefits for virtually everyone from children to seniors. Researchers aren’t sure exactly how, but studies show that tai chi improves the quality of life for breast cancer patients and Parkinson’s sufferers. Its combination of martial arts movements and deep breathing can be adapted even for people in wheelchairs. And it has shown promise in treating sleep problems and high blood pressure.

Flexibility and strength. Tai chi is credited with so many pluses, physiological and psychological, that Chenchen Wang, an associate professor of medicine at Tufts University, set out earlier this year to analyze 40 studies on it in English and Chinese journals. Wang found that tai chi did indeed promote balance, flexibility, cardiovascular fitness, and strength. In a study comparing it with brisk walking and resistance training, a tai chi group improved more than 30 percent in lower-body strength and 25 percent in arm strength, nearly as much as a weight-training group and more than the walkers.

“Benefit was also found for pain, stress, and anxiety in healthy subjects,” adds Wang, who was influenced by her mother, a Chinese doctor, to study an integration of complementary and alternative medicine with Western medicine.

In a 2008 analysis, Harvard Medical School’s Gloria Yeh, an internist and assistant professor, reviewed 26 studies in English and Chinese and reported that in 85 percent of trials, tai chi lowered blood pressure. Other studies have shown it to reduce blood levels of B-type natriuretic peptide, a precursor of heart failure, and to maintain bone density in postmenopausal women. The nonprofit Arthritis Foundation offers its own 12-movement tai chi sequence.

Wang says more study is needed. Still, says New York Times personal health writer Jane Brody: “After reviewing existing scientific evidence for its potential health benefits, I’ve concluded that the proper question to ask yourself may not be why you should practice tai chi, but why not.”

Lesson One: Find a teacher. “Learning from a book or video just does not work,” says Greg Woodson, vice president of the international T’ai Chi Foundation and a teacher for 35 years. Students need real feedback from a teacher who can make sure exercises are done correctly “so the practice does not cause the type of injury it’s designed to alleviate,” he says. One example: Weight-bearing feet need to be flat on the floor to avoid knee stress, “an extremely subtle point that an experienced teacher will see.” Woodson suggests that if a teacher has less than 10 years of experience, you should make sure he or she has the backing of a school or a more experienced teacher.

Moderate coffee intake protects against stroke
May 11, 2012
Lisa Nainggolan

London, UK – A new meta-analysis, including the most contemporary studies that have examined coffee consumption and risk of cardiovascular events in a general population, has found that moderate intake may help protect against ischemic stroke

Presenting the results at the recent European Society of Hypertension (ESH) European Meeting on Hypertension 2012, Dr Lanfranco D’Elia (Federico II University of Naples, Italy) told heartwire: “The first message is that coffee intake is not associated with a higher risk of stroke,” which he says is reassuring. “Second, the analysis showed that low to moderate intake—one to three cups of coffee per day—was associated with lower risk of stroke in the general population, across a wide range of countries, including some in Europe, the US, and Japan.”

However D’Elia stressed that these results apply to the general population only and that findings with regard to coffee intake and risk in those with cardiovascular disease have been conflicting. Nevertheless, he believes that “one coffee a day is not dangerous for people with heart disease.”

D’Elia and colleagues performed a meta-analysis of the available prospective studies, including those that estimated baseline coffee consumption and risk of stroke in the general population, from 1966 to 2011. However, the majority of studies included were performed in the late 2000s, including a recent Swedish study and one from the Netherlands.

One to three cups of coffee per day was associated with lower risk of stroke in the general population.

For this analysis, coffee consumption was stratified into moderate (one to three cups/day), high (three to six), and very high (six or more) and compared with the reference category (zero to one). For each study, the values of relative risk (RR) and their confidence interval were extracted and then combined using a random effect model. Eight general-population studies were included in the analysis, for a total of 11 cohorts (484 757 participants, 7272 stroke events, follow-up two to 24 years).

In the pooled analysis, habitual moderate coffee consumption was associated with decreased risk of stroke (RR 0.86, 95% CI 0.75-0.98; p<0.02).

Stroke risk in the high-consumption category showed a trend in the same direction, toward a reduction (RR 0.87, 95% CI 0.70-1.08; p=0.02), which reached statistical significance upon sensitivity analysis with the exclusion of a single outlier study (RR 0.81, 95% CI 0.70-0.95; p=0.01).

Habitual very high coffee consumption was not associated with any effect on stroke risk (RR 1.05, p=0.71).

D’Elia said that unlike low to moderate coffee intake, both “high” and “very high” consumption showed a significant heterogeneity between studies.

Statistical analysis did not find any significant sources of heterogeneity (length of follow-up, publication year, gender, countries, etc) that affected the relationship between coffee intake and stroke risk, but he noted, “We cannot exclude the potential limitations of the analysis around the standardization of coffee preparation or different types of coffee.

“The results of this meta-analysis, which included prospective studies of samples of the general population, indicate that coffee consumption is not associated with a higher risk of stroke and that actually habitual moderate consumption may exert a protective effect independently from most identifiable confounders,” he concluded.

[Although I find the design of the site a bit complex and slow, it crunches and provides lots of data, and can connect you with other people with similar conditions.].









www.medify.com

From their “About Us” Link:

We’re a crack team of technologists, advocates, medical advisors, and problem solvers. We believe in the power of knowledge, backed with data from real experiences, to truly help people connected by a common purpose. We’re on a mission to make Medify the best place for people managing important health situations to discover what works for people like them, and to get help from those they trust most.

Most of us at Medify have managed important health situations for ourselves or our families. Some of us still are.

Co-founder Derek Streat knows the struggle firsthand. His battle to successfully manage his daughter’s medical condition—rare and life-threatening—is the inspiration behind Medify. Despite having world-class doctors, finding all the answers he wanted, especially those backed by data from real patients like his daughter, was difficult. Making sense of it was nearly impossible. And knowing what to do with it, even more daunting. Derek knew there were other families like him, and he knew there was a better way.

Together with co-founders, Jay, Talib and Gunnar, experts in developing advanced technology to generate valuable insights for consumers from complex, “hidden” data, they created Medify.

[The importance of Circadian rhythms are vastly underrated...]

Intense Light Prevents, Treats Heart Attacks, Study Suggests

ScienceDaily
Apr. 25, 2012 — There are lots of ways physicians might treat a patient after a heart attack — certain resuscitation methods, aspirin, clot-busters and more. Now University of Colorado medical school researchers have found a new candidate: Intense light.

“The study suggests that strong light, or even just daylight, might ease the risk of having a heart attack or suffering damage from one,” says Tobias Eckle, MD, PhD, an associate professor of anesthesiology, cardiology, and cell and developmental biology at the University of Colorado School of Medicine. “For patients, this could mean that daylight exposure inside of the hospital could reduce the damage that is caused by a heart attack.”

What’s the connection between light and a myocardial infarction, known commonly as a heart attack?

The answer lies, perhaps surprisingly, in the circadian rhythm, the body’s clock that is linked to light and dark. The circadian clock is regulated by proteins in the brain. But the proteins are in other organs as well, including the heart.

Eckle and Holger Eltzschig, MD, a CU professor of anesthesiology, found that one of those proteins, called Period 2, plays a crucial role in fending off damage from a heart attack. With an international team of expert scientists, including collaborators from CU’s Division of Cardiology and the mucosal inflammation program, they published their findings in the April 15, 2012 edition of the research journal Nature Medicine.

During a heart attack, little or no oxygen reaches the heart. Without oxygen, the heart has to switch from its usual fuel — fat — to glucose. Without that change in heart metabolism, cells die and the heart is damaged.

And here’s where the circadian rhythm comes in. The study showed that the Period 2 protein is vital for that change in fuel, from fat to glucose, and therefore could make heart metabolism more efficient. In fact, Strong daylight activated Period 2 in animals and minimized damage from a heart attack.

Future studies will try to understand how light is able to change heart metabolism in humans and how this could be used to treat heart attacks in patients.

[More and more evidence on the relationship between noise, pollution and heart disease]

Heart Attack Survivors Living Close to Highways Face Higher 10-Year Death Risk

ScienceDaily
May 7, 2012

Living close to a major highway poses a significant risk to heart attack survivors, reinforcing the need to isolate housing developments from heavy traffic areas, a Beth Israel Deaconess Medical Center study concludes.

Writing in the May 7 edition of Circulation, researchers found heart attack survivors living less than 100 meters or 328 feet from a roadway have a 27 percent higher risk of over within 10 years than survivors living at least 1,000 meters away. That risk recedes to 13 percent for those living between 200 and 1,000-meter or 656 to 3,277-feet from the roadway.

“Living close to a highway is associated with adverse cardiovascular outcomes in those with underlying cardiac disease,” says Murray Mittleman, MD, DrPH, a physician in the CardioVascular Institute at Beth Israel Deaconess Medical Center, an Associate Professor of Medicine at Harvard Medical School and director of BIDMC’s cardiovascular epidemiological research program. “Besides air pollution, exposure to noise could be a possible mechanism underlying this association.”

The Onset study of 3,547 heart attack survivors in 64 community hospitals and tertiary care medical centers recorded 1,071 deaths over 10 years. Of that total, 63 percent of the patients died of cardiovascular disease, 12 percent died of cancer and 4 percent expired from respiratory disease. Researchers analyzed factors such as personal, clinical and neighborhood-level characteristics such as income and education.

“People with lower levels of education and income are more likely to live in communities closer to a major roadway, so they are bearing a larger burden of the risk associated with exposure than people with more resources,” says Mittleman.

In a study published earlier this year, a team led by Mittleman found air pollution, even at levels generally considered safe by federal regulations, increases the risk of stroke by 34 percent. Exposure to ambient fine particulate matter, generally from vehicle traffic, was associated with a significantly higher risk of ischemic strokes on days when the EPA’s air quality index for particulate matter was yellow instead of green.

These finding provide new evidence that long-term exposure to roadways is associated with an increased risk of death in patients with underlying cardiovascular disease.

“Clinicians need to educate their patients on the risks posed by particulate matter pollution and encourage patients with cardiovascular disease to avoid unnecessary exposure to traffic,” says Mittleman.

“On a public policy level, city planners should consider locating housing developments away from the most heavily trafficked roadways.”

“This study adds to the growing knowledge linking roadways and traffic to health problems, even death, especially among those with pre-existent disease — in this case a previous heart attack,” says Dan Costa, ScD, DABT, National Program Director for Air Climate & Energy Research in U.S. Environmental Protection Agency Office of Research and Development Research.

In addition to Mittleman, co-authors include Joshua I. Rosenbloom, MPH, Elizabeth H. Wilker ScD, of the BIDMC Cardiovascular Epidemiological Research Unit; Kenneth J. Mukamal MD. MPH of BIDMC’s Division of General Medicine and Primary Care; and Joel Schwartz, PhD of the Harvard School of Public Health.

The study was funded by the US Environmental Protection Agency and the National Institute of Environmental Health Science. Wilker was supported by a grant from the National Institutes of Health and Rosenbloom was supported by the Harvard Medical School Scholars in Medicine Office.
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