An important new study caught my eye.  In last week’s British Journal of Sports Medicine, Andrea Menafoglio and her colleagues from Bellinzona, Switzerland published (epublished ahead of print) a report entitled, “Cardiovascular evaluation of middle-aged individuals engaged in high-intensity sport activities:  implications for workload, yield and economic costs.”(1)

The study is important because it addresses the issue of cardiovascular screening in adult, recreational athletes, an area that’s received very little attention.

By comparison, the issue of cardiac screening for young, competitive athletes has received a great deal of attention over the past 25 years.  Many prominent medical scientific organizations have issued recommendations for pre-participation screening in young athletes, including the American Heart Association (1), American College of Cardiology (ACC), American Academy of Family Practice (AAFP), American Academy of Pediatrics (AAP), American College of Sports Medicine (ACSM), American Medical Society for Sports Medicine (AMSSM), just to name some of the American organizations.

These recommendations form the basis for the widespread use of mandatory pre-participation screening in secondary schools and colleges. The goal of such screening programs is to reduce the number of fatalities from sudden cardiac problems that arise during sporting activities.   The successes and pitfalls of such screening programs have been reported and the findings have engendered lively debate about what elements to include in screening programs, their effectiveness, and justification of their cost.

In this new study, the investigators report on a “real world” glimpse into cardiovascular screening in adult, recreational athletes.  Their aims were to evaluate the practicality of such a screening program, to measure the prevalence of previously unrecognized cardiovascular conditions in this group, and to determine the costs associated with initial screening and follow-up evaluation of athletes with an abnormal initial evaluation.

The Study

The investigators enrolled 785 athletes, aged 35-65 years (mean, 46.8 years), who engaged in “high-intensity sports” for at least 2 hours per week.  The athletes’ sports included running (in 33%) and cycling (in 24%), among others.  The majority of subjects (73%) were male.  The athletes were primarily “amateur” (69.7), but the group included some who competed in regional (23.7%), national (4.6%), or international competition (2.0%).

Athletes with a known history of cardiovascular disease, except for treated high blood pressure, as well as athletes who had previously undergone cardiac screening within the previous year were excluded.

Each athlete underwent a cardiac screening evaluation according to the current guidelines established by the European Association of Cardiovascular Prevention and Rehabilitation (EACPR).  The evaluation was free to each athlete and included:

• Thorough personal and family medical history
• Physical examination
• ECG
• Estimation of the individual’s cardiovascular risk using the Systemic Coronary Risk Evaluation (SCORE) chart for Switzerland
• Blood testing for total cholesterol and serum glucose.

The SCORE chart was used to estimate the athlete’s 10-year risk of death due to atherosclerotic heart disease based on gender, age, total cholesterol level, systolic blood pressure, and smoking status.  Athletes were deemed at “high risk” if their predicted risk was >5% or if any single risk factor (eg, total cholesterol, blood pressure) was markedly abnormal.  The cost of this screening evaluation was reported to be $130 per athlete, or $102,050 total.

The Findings

The screening evaluation was abnormal in 112 athletes (14.3% of the total):

• 5.1% due to abnormal, “pathologic” ECG findings
• 4.7% because of abnormal physical examination
• 1.6% due to a “positive” personal or family medical history
• 4.1% because an athlete was at “high risk” for atherosclerotic heart disease

Each of these athletes then underwent subsequent, more detailed testing to shed more light on the athlete’s cardiac circumstance and to determine if a true cardiac problem was present.  These tests included, among others:  echocardiogram (an ultrasound examination of the heart’s structure and function); stress test; 24-hour blood pressure monitoring; 24-hour Holter monitoring (of the ECG, continuously, to evaluate for arrhythmias); cardiac MRI; coronary angiography; and tilt testing.  A total of 194 such tests were performed and these additional tests had a total cost of $54,556.

In the end, a new, previously unsuspected cardiovascular problem was identified in 22 (or 2.8% of the 785) athletes:

• 8 with hypertension
• 5 with mitral valve prolapse and at least moderate mitral regurgitation
• 3 with biscuspid aortic valve (2 with moderate aortic regurgitation and 1 with mild aortic stenosis)
• 1 with mild pulmonary valve stenosis
• 1 with vaso-vagal syncope
• 1 with Wolf-Parkinson-White syndrome
• 1 with hypertrophic cardiomyopathy (HCM)*
• 1 with significant coronary artery disease and “old” myocardial infarction*
• 1 with abdominal aortic aneurysm*

This group included 19 men and 3 women.  Of these 22 athletes with newly diagnosed cardiac conditions, 3 were deemed ineligible to participate in their sports because of unacceptably high risk of cardiovascular events (indicated by an asterisk, above).  Each of the 3 athletes who were deemed ineligible for sports activities were identified by an abnormal ECG during the initial screening.

The other 90 athletes with an abnormal initial screening evaluation were “cleared” on the basis of their subsequent testing.  We might refer to these athletes as the “false-positives”–those with an abnormal initial screening evaluation, but no real cardiovascular problem.

Interestingly, no diagnosis of coronary artery disease (CAD) resulted from the 76 exercise stress tests that were performed.

The Investigators’ Conclusions

The authors reached 4 main conclusions:

1. The screening program was effective in identifying a small, but significant, number of athletes with significant cardiovascular conditions that required treatment or monitoring.
2. The screening program was effective in identifying a very small number of athletes in whom continued participation in sports activities was thought to be dangerous.
3. Inclusion of the ECG in the initial screening evaluation was important.
4. The screening program was practical and the costs were reasonable.

My Thoughts

This study provides some pertinent data to help frame our discussions about cardiovascular screening for adult, recreational athletes.  The study population here appears to be typical in many regards, and I suspect the study results can reasonably be generalized to athletic populations far beyond Switzerland.

Adult, recreational athletes are not typically bound by the mandatory pre-participation cardiac screening programs that are used for young, competitive athletes.  They have to make their own decisions in this regard.  They must decide whether “getting checked out” is worth the expense.  Athletes might have a variety of relevant questions.  How likely am I to discover a previously unrecognized cardiac problem–particularly if I don’t have any symptoms?  What are the chances that I could be a false-positive–with the burden of additional diagnostic testing to sort things out?  What will this all cost?

Each of these questions now has an answer.

With regard to the first question, there is an approximately 3% chance of identifying a previously unrecognized, unsuspected, and presumably asymptomatic, cardiovascular condition.  On t op of that, there is an approximately 4% chance of identifying a high risk profile, based on risk factors, that deserves close follow-up.  And finally, there is an approximately 0.4% chance (3 athletes among 785) of identifying a serious cardiovascular condition that places an athlete at undue risk of sudden cardiac death during exercise.  It’s not clear from the study whether these risks are similar for men and women.

The second question also has an answer.  The chance of a false-positive, using this particular screening evaluation, was approximately 11.5% (90 athletes among 785).  That is a fairly large number.  Recall that each of these athletes required additional diagnostic testing–at additional cost–to establish that they didn’t actually have a problem after all.

The third question has also been answered–at least in Switzerland.  The average cost of the screening program–initial evaluation plus the costs of additional testing that was needed–was $199 per athlete.  The cost for the 663 athletes who had a normal screening evaluation was only $130.  Obviously, the costs for the remaining 122 athletes, with an abnormal screening evaluation, and who required additional diagnostic testing, were greater.  All of these costs would be much higher in the United States, I suspect, and this issue is compounded by the fact that most health insurance policies don’t cover screening evaluations such as these.  For many American athletes, these expenses would be out-of-pocket.

At any rate, this new information will be helpful as athletes have discussions with their physicians about whether or not to pursue cardiac screening.

Those are my thoughts about the issue from the athlete perspective.

From the physician perspective, I think it’s important to note that all of the stress testing results were normal.  These are expensive tests.  We need to keep in mind that the pre-test probability of an abnormal finding in an asymptomatic population of exercisers is extraordinarily low.  Perhaps, it’s best to think twice before ordering a stress test in this situation.

And finally, from the perspective of the event organizer, the prevalence data here is enlightening.  Governing bodies and race directors should be aware that several percent of participating athletes will have unsuspected cardiovascular problems, including 0.4% who are at high risk of sudden cardiac death during exercise.  These numbers should inform safety planning efforts.  It shouldn’t be surprising that we have a small number of cardiac emergencies and even fatalities in recreational competitions involving adult athletes.

Reference:

1.  Menafoglio A, Di Valentino M, Porretta AP, et al.  Cardiovascular evaluation of middle-aged individuals engaged in high-intensity sport activities:  implications for workload, yield and economic costs.  Br J Sports Med 2014;01-6.  doi:10.1136/bjsports-2014-093857.