Two-Part Cascade Screening For Familial Hypercholesterolemia
Cascade screening can involve two independent tests or screens. The first is checking the lipid levels of all first degree relatives (children, parents, siblings) of the affected individual. Sometimes, DNA testing (genetic testing) is also done. Initially this DNA testing is done in the affected individual. If the DNA test reveals the specific, mutated gene that causes familial hypercholesterolemia then physicians can look for this specific DNA mutation in first degree relatives. Physicians can use both kinds of tests to “rule in” or “rule out” the presence of FH in family members.
Is It Necessary For Every Family Member?Most medical physicians and lipids specialists, including the National Lipid Association, agree that at the very minimum, all first degree relatives of the affected person over the age of two should be screened for FH. A first degree relative is anyone of direct descent, including children, parents and siblings. Once each of these individuals has been tested, any of them who have FH should then have their own first degree relatives screened. This scenario is called cascade screening because the results tend to create a waterfall effect of tests for family members often resulting in multiple diagnoses among blood relatives.
There are specific ethnic groups that tend to have higher concentrations of individuals with Familial Hypercholesterolemia compared to the general population. South African Afrikaner, Ashkenazi Jewish, Lebanese, and French Canadian populations are some examples of groups that are more likely to have FH, so screening of all family members is particularly important within these groups. The genetic reason that there are more people with familial hypercholesterolemia inside particular groups is known as the Founder Effect. This is when particular groups over generations have tended to be more self-contained and less diverse than the larger, surrounding population. Genetic anomalies become more common as these groups move through time.
How Critical Is FH Screening?Familial hypercholesterolemia can be debilitating if not treated properly, leading to serious complications such as advanced cardiovascular disease, heart attack and even death. If caught early, however, there are a number of treatment options that can dramatically slow the progression of symptoms as well as eliminating high cholesterol levels and other symptoms. For families with homozygous FH, early treatment is essential, as this form of the disease is more severe and can cause health problems and severely elevated lipid levels as early as age two. Because fewer than one in four individuals know they have the disease, the majority of people who have it are unaware of it. Cascade screening is an effective tool that reduces the number of untreated cases. Caught early, a variety of treatments can be used to improve heath, reduce cholesterol and give patients a new lease on life.
By undergoing cascade testing, your family members can ensure that every person with familial hypercholesterolemia is properly diagnosed, and treatment can commence as early as possible. With early intervention, the right treatment protocol can lengthen their lives and help them make the best health decisions possible.
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