Treatment would reduce risk of genetic condition that can lead to early death
THURSDAY, Sept. 13 (HealthDay News) -- A simple blood test early in life could identify children with familial hypercholesterolemia, a genetic condition that causes high cholesterol levels and greatly increases the risk of early death from heart disease, a British study finds.
Drug treatment could eventually be started to reduce that risk. And a side benefit could be identification of parents unaware that they were carrying the gene for the condition, the researchers said.
No elaborate genetic test would be needed, just a blood reading to find which children have abnormally high levels of LDL cholesterol -- the "bad" kind associated with blockage of arteries, said Dr. David Wald, lead author of the report.
The findings are published online Sept. 15 in the British Medical Journal.
An analysis of 13 studies that included 1,907 people with the condition showed that screening was most effective when done early in childhood, said Wald, a consultant cardiologist and senior lecturer at the Wolfson Institute of Preventive Medicine in London.
"The work we've done establishes the age at which screening performance is optimized," Wald said. He and his colleagues are planning "a limited implementation study that is necessary to establish feasibility," he said. The proposal is to include a cholesterol test at about 15 months of age, as part of a child's normal health-care routine.
Screening newborns or young adults was much less effective, the report said.
"Our study shows that a test would identify 88 percent of cases of familial hypercholesterolemia, with only one in 1,000 misidentified," Wald said.
The more common form of the condition, caused by a single gene, is estimated to occur in one of every 500 people in Great Britain and the United States. There are rare, much more severe cases of the disorder in which someone carries two faulty genes.
"It is the most important known and reversible cause of premature heart attack," Wald said. "It carries a 20- to 39-fold higher risk of dying of a heart attack before age 50."
The test proposed in the report would look for a blood LDL cholesterol level 1.5 times higher than the average for a child in the population being tested. "The first thing we would do then would be to test the parents," Wald said. "One of them would have to be affected, because it is a genetic condition. We could offer the parents immediate treatment."
Treatment for a parent or child carrying the gene would most likely be a cholesterol-lowering statin drug, he said.
A study reported last month by cardiologists at the University of Amsterdam in the Netherlands found that early long-term statin therapy prevented artery damage in children with familial hypercholesterolemia. The study included 214 children who were treated with statins for an average of 4.5 years.
The study participants ranged from 8 to 18 years old. The report described the results as "supporting the concept that statin treatment should be initiated in childhood." The study found "no adverse effects on sexual maturation or growth," the researchers added.
The British researchers "make a very reasonable case for screening" for familial hypercholesterolemia, said Dr. Steven Nissen, chairman of the department of cardiovascular medicine at the Cleveland Clinic. "I have a cluster of patients I follow, and I know you can give statins to children as young as 13," he added.
But the study alone "is not enough to change our current practice," Nissen said.
"The argument is that their lives would be shortened and the quality of life diminished" without screening, Nissen said. "But a decision about doing this in the United States must involve a lot more thinking and a lot more economic analysis, because it involves a huge screening program."
For more on familial hypercholesterolemia, visit the U.S. National Library of Medicine.
SOURCES: David Wald, M.D., consultant cardiologist, Wolfson Institute of Preventive Medicine, London, England; Steven Nissen, M.D., chairman, department of cardiovascular medicine, Cleveland Clinic; Sept. 15, 2007, BMJ Online
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