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Boston, MA— An article, published in Circulation by Laurel K. Leslie, MD, MPH from the Tufts Clinical and Translational Science Institute (CTSI) and colleagues from Tufts Medical Center and Floating Hospital for Children at Tufts Medical Center, has evaluated the lifesaving benefits and costs of screening programs for the prevention of sudden cardiac death (SCD) in children and adolescents. The authors found that screening can save lives, but that because it targets rare conditions and available tests have limited accuracy, screening for SCD is costly, compared to other life-saving measures.

Although rare, SCD often receives widespread attention because it is unexpected and can occur during childhood. Those factors have prompted many parents and policy makers to support screening programs. To help decision makers and the public understand whether more SCD screening is warranted, the authors, including collaborating clinical researchers from Children’s Hospital Boston, compared the potential life saving benefits (measured in terms of life years saved) to program costs. They considered two groups thought to be at elevated risk: school-aged children taking stimulants, which are often used to treat Attention Deficit Hyperactivity Disorder (ADHD), and adolescents playing organized sports. The research team determined that each year of life saved would cost from $90,000 (to screen adolescents before they participate in sports) to $200,000 (to screen children before they take ADHD medications).

Although there is no hard and fast line separating worthwhile and expensive public health interventions, programs can be compared to get an idea of their value. For example, interventions that cost $90,000 to $200,000 per life year saved are considered expensive, compared to other interventions, which often save life years at $50,000 to $100,000, or even less. The results of this study suggest that finite public health resources might be better spent elsewhere.

The “human cost” of screening suggests its true price may be even higher. Because conditions causing SCD are so rare, even an occasional “false positive” means that for every previously undiagnosed child accurately identified, many children who would never have died from SCD may be labeled as being at-risk.

The research team stressed that the cardiac conditions causing SCD in children are incredibly rare. Many are cardiac conditions are genetic and there may be a family history of early (< 50 years of age) or unexplained SCD in a family member. Dr. Leslie advises that “the most concerning family history in a child is when a parent or sibling is diagnosed with a likely familial cardiac disease; those children should certainly be evaluated.” Since some disorders that cause SCD may not be identifiable on an ECG until late adolescence or early adulthood, an ECG in a parent with a positive family history may provide more information than an ECG in a child. Another indication to consult with a doctor is if a child reports any experiences of fainting or shortness of breath with strong emotions or during exertion (not related to a medical condition like asthma).

Using age alone to identify those at risk of heart disease or stroke could replace current screening methods without diminishing effectiveness, according to a groundbreaking study published today in the open access journal PLoS ONE.

Existing screening methods which include measuring cholesterol and blood pressure are expensive and time consuming. The authors of the new study from Barts and The London Medical School say that this finding could save thousands of lives by making it easier for more people to have access to preventive treatment.

The new study compared screening using age alone with screening using age and multiple risk factors, measured via blood tests and medical examination. The authors used existing data to estimate the effects of the two screening approaches on a modelled population of 500,000 people.

Age screening alone using a cut off of 55 years had an 84 per cent detection rate and a 24 per cent false-positive rate. This is equivalent to correctly identifying 84 per cent of all the people in a population who will have a stroke or heart attack, while incorrectly identifying 24 per cent who will not. Current screening methods can achieve the same 84 per cent detection rate with a false-positive rate that is only slightly less – 21 per cent.

Professor Sir Nicholas Wald is lead author and Director of the Wolfson Institute at Barts and The London School of Medicine and Dentistry, part of Queen Mary, University of London. He said: “This study shows that age screening for future cardiovascular disease is simpler than current assessments, with a similar screening performance and cost effectiveness. It also avoids the need for blood tests and medical examinations.

With age screening all individuals above a specified age would be offered preventive treatment. Everyone would benefit because, for blood pressure and cholesterol, the lower the better. The policy of selecting people above a certain age is, in effect, selecting people at high risk. It recognises that age is by far the most important determinant of that risk with other factors adding little extra prognostic information.

“Prevention is better than measurement,” Professor Wald added. “Identifying people at high risk of cardiovascular disease needs to be greatly simplified, enabling people to obtain easy access to preventive treatment from nurses and pharmacists as well as from doctors.

“Offering appropriate preventive treatment to everyone aged 55 and over in England and Wales could prevent over 100,000 heart attacks and strokes every year.”