Is the universal pre-participation screening of young athletes justified? 

No, says Eva Prescott, Bispebjerg University Hospital, Copenhagen, Denmark

Although the debate for and against the screening of athletes has raged for several years, there is still little actual data clarifying many questions, and no data that can be considered hard evidence. By meticulously gathering data from Veneto over more than two decades, Corrado and colleagues have documented a decline in SCD incidence among athletes after the implementation of screening which was not accompanied by a decline in non-athletes. However, although the data are truly impressive, by no means do they represent conclusive evidence that screening saves lives. The data describe a temporal association that may or may not reflect cause and effect. One indicator that the association is not causal is that conditions not picked up by screening, such as CAD, myocarditis and congenital coronary abnormalities, also declined. 
 
It must be emphasised that the identification of an abnormal ECG or abnormal echo – or even of disease – is not the same as identifying an athlete at risk. Likewise, disqualifying someone from participation in competitive sport is not the same as preventing an SCD. Because of the extremely low rate of SCD, looking for the athlete who will eventually die from SCD is like looking for a needle in a haystack. 
 
From the athletes’ point of view the risk of being disqualified from sport, and in many cases their livelihood, must be weighed against the risk of SCD. Depending on the rate of preventable SCD in a particular population and which screening programme is employed, the number of disqualified athletes for each life saved may be 2000 or more - and still not all SCD will be prevented.   

Screening programmes which include more detailed testing - ECG, stress testing, imaging - can reduce the number of athletes who are screening-positive, and by doing so may also reduce the number of SCDs potentially prevented. We do not at present know the value of elaborate screening programmes in terms of the only truly valid endpoint, preventing SCD. What we do know is that more elaborate screening programmes will increase the costs of screening. 
 
The WHO has said that a number of criteria should be met before introducing a screening programme - that the condition should be an important health problem, that there should be a suitable test and accepted treatment for the condition, that the screening programme should be acceptable to the athletes, and that the economic costs should be balanced in relation to medical expenditure as a whole. 
  
In the case of screening athletes to avoid SCD, most of these criteria pose problems. The incidence of SCD among young athletes has been reported to be much lower in countries outside Italy, the causes of SCD have been shown to differ between populations, with varying proportions likely to be identified by screening, and little is known of ECG-screening performance in non-Caucasians. These facts affect the utility and cost-effectiveness of a screening programme. Furthermore, large-scale screening will result in a considerable number of athletes being inappropriately barred from participating in sports, the psychosocial, ethical, prognostic and even legal implications of which need to be elucidated.  
  
Moreover, some studies indicate that risk of SCD is not higher among competitive athletes as a whole than among non-athletes. Even with proven efficient and cost-effective screening programmes, within European healthcare systems it may be hard to justify compulsory pre-participation screening for athletes but without screening those youngsters who have not chosen to participate in competitive sports.
  
Each sudden cardiac death in a young person is tragic, whether athlete or non-athlete. This is undisputable. But we as cardiologists must keep a cool head. Before recommending the screening of athletes based on insufficient data from a single region in Italy, a number of issues need clarification. Above all, efforts should be made to gather the necessary data, including registries of SCD in the young, to enable a prevention strategy which is evidence based, is cost-effective and respects the autonomy of the athlete.