Cascade Screening for Familial Hypercholesterolemia

Familial hypercholesterolemia is an autosomal dominant disorder that affects the way that the blood handles cholesterol, resulting in abnormally high concentrations of LDL cholesterol in the blood. This can have serious consequences because it leads to coronary heart disease, heart attacks, and other heart problems at a premature age. It is caused by a single mutation in one of several genes, including the LDL receptor, apolipoprotein B, or proprotein convertase subtilisin/kexin type 9. The vast majority of people with FH are undiagnosed, leaving them at serious risk for major cardiovascular problems, since major lifestyle, diet, and medication changes are needed to reduce the risks. Cascade screening is a diagnostic method that can help identify individuals with FH early on, so they can get the therapy they need and live longer, healthier lives.

Affecting one in every 300-500 people worldwide, it is one of the most common inherited genetic disorders. Because it is an autosomal dominant disorder, this means that an individual only needs to have one parent with FH to be at a 50% risk of having it themselves. If both parents pass an FH mutation down to their offspring, the resulting disorder is much more serious than the more common form of FH. Only one in one million people are estimated to have the most severe form of this genetic disorder, although more recent studies suggest that this number might actually be bigger. However, as rare as the more serious form of FH is, it’s important to consider that if one member of a family is diagnosed with FH, it is not a possibility but rather a certainty that other members of the family have the genetic disorder as well.

Since FH is an inherited disease, tracing it through family lines is one of the most effective ways to find the people who are at risk for a genetic condition in order to treat them properly. Cascade screening is the name for one such mechanism. When people receive a diagnosis of FH, they become what is known as an “index case.” Cascade screening then is the process of testing their immediate biological relatives to figure out which other members of the family also have the FH gene. First, second, and third degree biological relatives are all candidates for cascade screening.

the Family Heart Foundation is dedicated to providing educational information about FH in order to help those who don’t know that they have the disease identify it and seek potentially life-saving treatments. Our national FH registry is called CASCADE FH, in order to highlight the importance of cascade testing to relatives of anyone who has a diagnosis. If you have received a diagnosis of FH, we highly encourage you to join the registry and help us track disease patterns, therapy trends and patient quality of life to enable research in bettering FH diagnosis and care.

If you want to learn more about FH, browse the Family Heart Foundation website to learn everything you need to know about risk factors, diagnosis, treatment, and next steps for individuals who discover that they have FH. Even if you’ve never considered the possibility that you might have FH before, it’s worth learning everything you can to decide if you might be candidate for the disorder. After all, what you don’t know about FH can kill you.