For the past four years cardiologist Josh Knowles, MD, PhD, has been treating patients at Stanford who have a little-known but common genetic heart disease called familial hypercholesterolemia, or FH, an often undiagnosed condition that causes lifelong high cholesterol. FH is thought to be the cause for 12,500 heart attacks each year among people under the age of 60 in the U.S., he told me.
Catching the disease early on can save lives, he emphasizes.
"Two individuals may have the exact same high cholesterol level, but if one has FH, they're at much higher risk," Knowles explained. "They need to be treated more aggressively and their relatives need to be aware of the risks for themselves."
Now a panel of international experts recommends that genetic testing for FH become the standard of care in the United States for patients thought to have the condition and their relatives — as it has been since the early 1990s for many other countries. Knowles, a member of the panel which published its recommendations this month in the Journal of the American College of Cardiology, has seen firsthand the benefits of genetic testing which he offers routinely to his patients.
"Genetic testing should be offered as part of standard of care for FH," says Knowles, who also researches the genetic causes of FH. "Part of the reason it has not been offered is that providers have not fully understood the potential benefits."
Prohibitive costs in the past have limited the use of genetic testing in general for patients, but as availability has increased and costs have declined its use has become increasingly more routine for a variety of disorders. Four or five years ago, costs ran between $2,000 to $2,500 for FH testing, but have since dropped to just a few hundred dollars, Knowles said, although its use is currently far from routine.
The paper, which was based on a review of the literature, found that genetic testing for FH not only improved diagnosis but led to better treatment plans, and encouraged patients to be more vigilant in taking their prescribed lipid-lowering medications such as statins.
"Despite FH being a genetic disorder, genetic testing is rarely used," the authors write. By making genetic testing routine, not only would it improve diagnosis, it would also lead to better identification of relatives with the disease. FH is a condition that affects families, they write.
An estimated 1 million people in the United States have FH yet only 10 percent have been diagnosed, the paper says. Many of these people might realize they have high cholesterol, but have no clue they also have FH. Since they are born with high levels of LDL — the so-called bad cholesterol — that build up in the arteries and can ultimately choke off blood flow to the heart, if not treated, they’re at much higher risk of heart attacks and stroke.
The panel was convened by the FH Foundation to assess the use of genetic testing for the condition. Knowles is a volunteer advisor for the foundation.
Photo by Robina Weermeijer