running

Cardiac Arrest During Long-Distance Running Races: A New Report

January 17, 2012 By Larry Creswell, MD 3 Comments

This past week, the results from an important study on the heart risks of long-distance running was reported in the New England Journal of Medicine.

A group of investigators from Boston looked at the experience of ~11 million runners who took part in half marathon or full marathon races in the United States between 2000 and 2010. This is the largest study of its kind ever undertaken.

The important findings were:

-59 athletes had cardiac arrest and 42 of those died

-For marathon runners the risk of cardiac arrest was 1.01 per 100,000 participants

-For half marathon runners the risk of cardiac arrest was 0.27 per 100,000 participants

-The risk for men was several-fold greater than for women

-The majority of deaths occurred during the last 6 miles of the marathon or the last 3 miles of the half marathon

-From medical records, the cause of cardiac arrest could be determined for 31 victims (23 of whom died). In most of the cases where the athlete died, there was a specific heart condition that was responsible:

—Hypertrophic cardiomyopathy (HOCM) in 8

—Possible HOCM in 7

—Hyperthermia in 1

—Arrhythmogenic right ventricular cardiomyopathy in 1

—Hyponatremia in 2

—No specific cause in 4

Some important, NEW observations were:

–The frequency of cardiac arrest is extremely low….and even lower than previously thought.

–The survival rate from cardiac arrest was surprisingly good, at 29%. This is much higher than previous reports for out-of-hospital cardiac arrest. It suggests that bystander CPR and early defibrillation may be readily available at race venues.

–The risk is greater in marathons, compared to half marathons. The reason(s) are not yet clear.

This new report provides the most comprehensive information yet on cardiac arrest during running races. Athletes should be encouraged by the extremely low rate of cardiac arrest and with the favorable survival rates reported. Athletes should also take note that the cause of cardiac arrest was most often due to an underlying cardiac condition that might be discoverable BEFORE participating in a traning program or race. It’s reasonable to conclude that a pre-participation visit to the doctor for a careful physical examination and, potentially, cardiac testing might reduce an athlete’s chances of being a victim.

Cold Weather and Sudden Death in Marathon

January 12, 2010 By Larry Creswell, MD 2 Comments

Jackson, Mississippi hosted the 3rd annual Mississippi Blues Marathon this past weekend. The temperatures were bitter cold (17 degrees at the start), but 1,400 or so folks braved the cold to finish the marathon or half marathon events. I twisted my ankle about 10 days ago, or I might have joined my many running friends for the event.

The day was marred by the tragic death of a 40-year-old local man who died in the final mile while he was running the anchor leg for a 5-man relay team. He collapsed suddenly within sight of one of Jackson’s major hospitals. He received immediate medical attention, was taken to the hospital, and was pronounced dead. The events are described in this article from the local Clarion-Ledger newspaper. The coroner did not immediately release a statement about the cause of death.

I’ve received many questions since Saturday about this tragedy and I thought I’d share some of my thoughts here at the blog.

I’ve talked previously here at the blog about causes of death in middle-aged athletes. Here again, the most likely cause of death is cardiac, and specifically a fatal arrhythmia in the setting of coronary artery disease (CAD). A variety of other causes is possible, though, and we will only learn the true cause when an autopsy is completed. Other possibilities would include undetected hypertrophic cardiomyopathy (HCM), some sort of congenital heart disease, or even catastrophic neurologic event such as a stroke.

I’ve been asked about the role that the cold temperature on race day might have played in this runner’s death. It’s an interesting question. Since there are only a handful of deaths annually in the U.S. at marathons, the issue of race-day temperature on the risk of sudden death hasn’t really been studied….and probably can’t be studied. I recall that it was also a cold day in Detroit this fall when 3 runners died of cardiac causes at the Detroit Marathon. Thankfully, deaths at marathons are rare, at only 1 per ~100,000 runners.

If we think about this problem OUTSIDE the setting of athletic pursuits, it turns out that cold temperatures actually ARE associated with an increased frequency of heart attack. We know this from studies that show that heart attacks occur more often in the winter. And it’s generally thought that the cold temperature itself produces some sort of extra stress that might trigger the heart attack. That said, the effect of temperature is relatively small….and heart attacks occur in all temperatures.

We often think about the added stress that HOT or HUMID weather places on athletes in endurance events. But the cold can also add stress. The issues related to cold-weather running are summarized very nicely by Tim Noakes, MD, in his book, Lore of Running, in a section called Cold Hazards. The most important medical concern during cold weather running is hypothermia. And, interestingly, the slower you run (or walk), the more important it becomes to dress warmly.

And lastly, what could have been done to prevent this death? Without more information about his cause of death, I can’t be sure. And I don’t know anything about this runner’s medical history or preparation for the event. Perhaps nothing could have been done. But I’ve said it here at the blog before….if you’re a 40-year-old endurance athlete, it is wise to have a physician, get screened for possible unrecognized heart disease, and treat all warning signs such as chest pain or unusual shortness of breath seriously. Get checked out. And make certain that your goal event makes sense in the context of your medical condition and your athletic preparation for the event.

In the News: Why Do Athletes Live Longer?

December 8, 2009 By Larry Creswell, MD 2 Comments

I came across an interesting article in the November 30th edition of U.S. News & World report online and thought I’d share it with you here. It’s interesting reading.

There is an abundance of data that indicate beneficial effects of exercise….and one of those benefits may be a longer life-expectancy. But why?

Last week, in the online version of Circulation, an American Heart Association medical journal, a group of investigators in Hamburg, Germany report some novel findings in young and middle-aged track and field athletes in an article, entitled “Physical exercise prevents cellular senescence in circulating leukocytes and in the vessel wall.”

It turns out that endurance athletes have longer telomeres–the DNA at the tips of the chromosomes that protect cells–in their white blood cells compared to non-athletes. The authors speculate that this feature provides, over a lifetime, an anti-aging effect.

It’s also interesting to note that three American scientists shared the Nobel Prize in Medicine this year for their work, over many years, to understand the telomeres and the process of cell death and aging. You can read about this in a report at cnn.com from earlier this week.

Scientists are only beginning to understand the process of aging in humans, but it is nice to know that endurance athlete’s may have a leg up!

Jim Fixx, Runner, 1932 – 1984

November 16, 2009 By Larry Creswell, MD Leave a Comment

Here at the blog, we’ve talked about a variety of cardiovascular diseases that affect athletes. Coronary artery disease, that can lead to heart attack, is the most common cause of sudden death in athletes over the age of 40.

Years after his death, many will remember Jim Fixx for the contribution he made to the popular enjoyment of running. His story is very compelling. In his mid-thirties, he was overweight (240 pounds), a 2-pack-a-day smoker, and sedentary. But he got the urge to do something healthier….and took up running at age 35. He would lose more than 60 pounds and became an example of how a healthier lifestyle was possible for ordinary folks.

In 1977, Fixx authored “The Complete Book of Running.” At the time, this was the best-selling non-fiction hardcover book ever published. He inspired countless Americans to take up the hobby of running.

Out for a run through the Vermont countryside on July 20, 1984, Fixx was found alongside the road, dead at the age of 52. An autopsy showed that he had severe blockages in all 3 of his coronary arteries….a setup for heart attack or sudden death.

On the face of it, Fixx’s death was stunning. His public persona was the picture of health. Yet we know that at the time of his death he didn’t have a personal physician. In fact, he hadn’t had a physical examination in years….despite his history of obesity and smoking. Moreover, he had a strong family history of coronary artery disease in his family: his father had his first heart attack at age 35 and died of his second heart attack at age 43.

We’ll never know if Fixx’s death was avoidable….but his story provides lessons for all of us middle-aged athletes who are pounding the pavement each day.

In my next post, I’ll talk about the problem of coronary artery disease, along with its risk factors, prevention, and treatment. And I promise to leave our readers with some useful advice on what they can do to prevent a story like Fixx’s.