New Test Determines Genetically-Linked High Cholesterol

A new genetic test could potentially diagnose genetically-linked high cholesterol more effectively than current methods.

High levels of low-density lipoprotein (LDL) can increase the risk of heart disease and stroke. Some patients with high levels of LDL cholesterol can improve the condition through diet and exercise. Those who cannot achieve improvements must seek medication-assisted treatments to prevent adverse health effects.

The new method, LipidSeq, uses next-generation sequencing technology to locate specific parts of an individual’s DNA for diagnosing high cholesterol. LipidSeq has the potential to provide cost-savings since it does not sequence the entire genome, according to a study published in Arteriosclerosis, Thrombosis, and Vascular Biology.

“Previous studies showed little yield in doing genetic testing,” said researcher Rob Hegele, MD. "This new method shows there is a benefit, especially when you can add the extra step of medically selecting those with a familial history of the disease."

Included in the study were 313 patients with LDL cholesterol levels above 5 mmol/L who were referred to the lipid clinic where the study was conducted.

Using LipidSeq, a genetic mutation was discovered in 67% of patients. Scientists reported that 44% were single genetic mutations, and 13% were polygenic DNA variants. Interestingly, the scientists also found that as cholesterol levels increased, the percentage of individuals with a genetic component increased.

LipidSeq is currently licensed in the United States to assist physicians in identifying patients with genetically-linked high cholesterol to provide the optimal treatment. Statins are typically used to treat patients with high cholesterol, and they are typically low-cost and well-tolerated; however, they may not help patients with genetically-linked high cholesterol.

If these patients are treated with statins, they may experience adverse effects and have to pay for ineffective treatment, which can cause a financial burden to both the patient and the healthcare system. A new class of biologic drugs, PCSK9 inhibitors, recently emerged that could offer effective treatment for these patients, however, these drugs are also much more expensive.

“With this testing method, we can pinpoint who needs these more expensive drugs and those that don’t,” Dr Hegele said. “This is particularly important in the US for patients who have to justify to their independent health insurer why they need a more expensive medication.”