A new study suggests that introducing more widespread screening for familial hypercholesterolemia (FH) could identify more than one million adults with the condition who are at increased risk for heart disease.
FH is a relatively common genetic condition impacting 1 in 250 people in the U.S. that results in abnormally high levels of low-density lipoprotein (LDL) cholesterol, which can cause atherosclerosis and other forms of heart disease in those affected.
While testing for cholesterol levels and other cardiovascular risk factors is recommended every 4-6 years in the U.S. in those aged 20 years and above, FH screening is not standard and genetic testing for this condition is not always covered by health insurance policies.
Some earlier testing for FH does happen in people with a known family history, but generally most people are not diagnosed until middle age when symptoms have already occurred.
“Currently, most individuals aren’t diagnosed with FH until they are in their 50s. If a young adult is identified to have FH, they would likely benefit from earlier and more aggressive treatment to prevent heart attack and stroke,” said study researcher Brandon Bellows, an assistant professor of medical sciences at Columbia University in New York City, in a press statement.
In this study, published in the Journal of the American Heart Association, the researchers estimated how many additional people with FH could be identified at an early age if more widespread testing was available.
The team used information from 50,000 individuals, aged 40–69 years, who participated in the UK Biobank project and had genetic samples and medical information collected between 2006 and 2010. They found 6.6 cases of FH per 1000 adults screened when both genetic tests and clinical features were combined.
The researchers then used this information to predict what percentage of a group of 40,000 U.S. adults (National Health and Nutrition Examination Survey) without genetic information had FH.
They estimated that 1.3 FH cases per 1000 individuals screened could be picked up using clinical data alone in those aged 20-39 years, which would increase to 4.2 cases per 1000 if genetic testing was also used.
“Combining clinical criteria with genetic testing could substantially increase the yield of screening for FH and identify more than 1 million U.S. adults with FH,” write the authors.
“We need to do more to support familial hypercholesterolemia screening programs,” says Bellows, who was first author on the paper. “Individuals with high cholesterol levels or with a family member that had a heart attack at a young age should undergo genetic testing for familial hypercholesterolemia. Early diagnosis and treatment of familial hypercholesterolemia are the best ways to reduce the risk of early heart attack or stroke.”
There were limitations in this study, in that most of the cohorts assessed were of European origin and aged between 40–69 years, but it adds to accumulating evidence supporting a broader rollout of earlier FH screening to help prevent later heart disease in the individuals affected.
