A Better Way to Screen Athletes?
For years, sports-medicine specialists have debated the best way to screen athletes for participation in sports. In recent years, much of the debate has focused on the use of electrocardiograms (ECG). Researchers disagree on how much information they should add to a medical history and a physical exam, and whether they’re worth the cost.
Now a group of Canadian investigators has come up with a radical proposal: Do the ECG and skip the physical exam. Their reasoning? Doctors’ time is expensive, and physical exams don’t actually tell you much about which athletes are going to have the heart problems that pose the greatest threat of death during competition. The team put the approach to the test in a large study, and their cost/benefit analysis makes the approach look pretty good.
“The history and physical do not have strong value to detect heart disease,” says lead investigator James McKinney, MD, MSc, a sports cardiologist at the University of British Columbia in Vancouver, Canada. “The ECG is by far the most sensitive way.”
But on closer inspection, the study reveals just how weak the evidence for any sort of screening is, and how much depends on the context of the healthcare system in which the screening takes place.
Is Screening Really Efficacious?
The argument for preparticipation screening begins with the premise that athletes often get hurt—and sometimes even die—because of the demands they put on their bodies. In theory, the right sort of screening could predict which athlete is most likely to suffer which kind of injury. These athletes could then be advised to refrain from the activity or to take steps to strengthen the body part in question.
On the basis of that argument, most organizations tasked with developing guidelines for healthy sports participation in Western countries have supported the concept of screening. But then the consensus breaks down.
The problem is that no one has shown that preparticipation screening of any kind actually prevents injuries. When two of the world’s leading authorities on the topic—the American College of Sports Medicine (ACSM) and the Fédération Internationale du Médicine du Sport (FIMS)—met in 2014 to hammer out their differences, they noted that, “to date, no large scale prospective controlled tracking programs have examined outcomes of the [preparticipation physical evaluation] with respect to injury prevention, sudden cardiac death (SCD) reduction, or other consequences of exercise and competition.”
To look at every kind of injury that might befall an athlete would be a herculean task. So much of the research has focused on the part of the screening that seems likely to yield the most important result: detecting heart abnormalities that could put athletes at risk for SCD.
SCD kills about 66 athletes a year, more than any other medical cause. The deaths occur when exertion triggers life-threatening ventricular arrhythmias. But up to 80% of at-risk athletes show no symptoms before an arrhythmia is triggered.
Faced with this challenge, various governments and healthcare organizations have formulated conflicting proposals for detection before tragedy strikes. The American Heart Association (AHA) guidelines combine medical and family history with a physical exam, but no ECG.
The European Society of Cardiology, in contrast, has endorsed the use of a 12-lead ECG, along with the AHA requirements. Italy mandates a physical exam along with a 12-lead ECG and a 3-minute exercise step test for all participants in organized competitive sports. In the United States, sports leagues and school districts have various requirements. In Canada, there are no preparticipation screening requirements for SCD or any other injury.
Evaluating Screening Components
To get a handle on what, if any, screening approach, or combination of approaches, is most accurate for identifying athletes at risk for cardiac disease at the least cost, Dr McKinney and his colleagues designed a two-phase study. In the first phase, they screened 714 athletes 12-35 years of age with the AHA questionnaire, a 12-lead ECG, and a physical exam by a physician. Each of the three components was evaluated separately for screening accuracy.
In the second phase, the investigators developed their own questionnaire, which they called the SportsCardiologyBC questionnaire. They conducted a literature search to find questions that differentiated neurally mediated syncope from cardiogenic syncope and benign from pathologic causes of chest pain and dyspnea. There were follow-up questions for athletes with symptoms. The questionnaire was designed to be administered by nonphysicians.
The investigators administered their questionnaire to 705 young athletes, along with a 12-lead ECG, but they did not conduct a physical exam and there was no physician present. Here, too, the questionnaire and ECG were evaluated separately for screening accuracy.
The physician-administered physical exam was eliminated in the second phase because, if it is not necessary to identify athletes at risk for cardiac disease, the cost of the screening would be significantly reduced.
In both phases of the study, the examiners referred athletes with positive findings to cardiologists for further evaluation.
The examiners referred nine people to cardiologists on the basis of the physical exams conducted in the first phase of the study, but none of those referrals resulted in a confirmed diagnosis.
The AHA questionnaire, also used in the first phase, led to 49 referrals, only one of which resulted in a diagnosis of a true disease.
The SportsCardiologyBC questionnaire, used in the second phase, resulted in 24 referrals, none of which led to a diagnosis of true disease.
By contrast, the ECG, used in both phases of the study, resulted in referrals for 21 people, six of whom had confirmed disease.
A Problematic Cost-Effectiveness Ratio
Because the physical exam didn’t catch any heart conditions that could be confirmed, Dr McKinney and his colleagues argue that it can be eliminated. The cost to screen an athlete in the first phase was Can$97.50 and in the second phase was Can$14.42.
That’s $72.83 in the first phase and $10.77 in the second phase in US dollars. But Canadian dollars cannot simply be converted to US dollars when it comes to healthcare costs, because the national healthcare system in Canada is very different from the privatized system in the United States. To start with, Canadian doctors get paid less and ECGs are less expensive.
In the United States, the out-of-pocket cost for an ECG ranges from $550 to $3300, according to New Choice Health, a medical-procedure survey site. However, the cost for mass screenings would likely be much lower.
Cost-effectiveness projections for mass screenings vary widely. If the physical exam and family history from the AHA guidelines are combined with an annual ECG screening, one group of investigators estimated that the cost would be a staggering $10.6 million to $14.4 million per life saved in the United States. But another group, using a one-time screen, found a cost-effectiveness of $76,100 per year of life saved for the combination of history, physical, and ECG, with the incremental cost of the ECG at $42,900.
The question for society is: How much is saving a life worth?
To complicate matters, although ECGs might be the gold standard for the detection of cardiac problems, they are far from perfect. Other studies have pointed out that false-positive results from ECGs could lead athletes to be unnecessarily excluded from sports participation, and therefore to suffer ill-health effects related to less exercise.
ECG vs Physical Exam: One, the Other, Both, or Neither?
Even if the cost of an ECG comes down and accuracy improves, questions remain about the potential for a physical exam to prevent injuries besides SCD. In some settings in the United States, there is no cost for a physical because some physicians volunteer their time, said orthopedic sports specialist Barry Boden, MD, from the Orthopaedic Center in Rockville, Maryland.
Like many sports-medicine experts, Dr Boden believes in the potential of physician-administered physicals to detect a range of problems. When he helps conduct sports screening at nearby Montgomery College, he typically checks the athletes’ necks and backs, examines their knees for stability and range of motion, watches them walk, and does “some different functional tests.”
But the potential for these tests to prevent knee, back, head, or any other type of injury remains unproven. One of the most studied functional tests, Functional Movement Screening, has had mixed results. For example, a study of female collegiate athletes showed that a low score indicated a fourfold increase in risk for injury. But a study of junior major hockey players (the highest tier in the Canadian Hockey League for players 16 to 20 years of age) showed no correlation between low scores and injury risk.
In their consensus statement, the ACSM and FIMS argue that even though there is weak scientific evidence to support any sort of preparticipation screening, it is still worthwhile for “human” reasons. They cite just one example: “For about half the athletes who get a [preparticipation examination], it is the only contact that person has with a health provider. Therefore, the PPE is often the only opportunity to provide health counseling related to sport, social, health, and behavior risk factors.”
So where does this leave sports doctors who are trying to help schools and sports teams around the world keep their athletes safe?
They can make use of guidelines issued by professional organizations. In addition to the AHA questionnaire, the American Academy of Pediatrics offers a detailed checklist endorsed by several other groups, Dr Boden points out.