Maintaining a low level of LDL, or “bad” cholesterol, is important for cardiovascular health, but extremely low LDL may also have risks, researchers report.
The scientists studied 96,043 people for an average of nine years, recording their LDL level biennially and tracking cases of hemorrhagic stroke, caused by the rupture of a blood vessel in the brain. About 13 percent of strokes are of the hemorrhagic type.
They found that compared with people in the normal range for LDL — 70 to 99 milligrams per deciliter of blood — people who had an LDL of 50 to 69 had a 65 percent higher risk of hemorrhagic stroke. For people with an LDL below 50, the risk nearly tripled.
LDL concentrations above 100, on the other hand, were not significantly associated with hemorrhagic stroke, even at levels higher than 160. The study, in Neurology, controlled for age, sex, education, income, diabetes, hypertension and other variables.
The senior author, Dr. Xiang Gao, an associate professor of nutrition at Pennsylvania State University, said that this does not mean that having a high LDL is harmless. “High LDL is a risk for cardiovascular disease, and a level above 100 should be lowered,” he said. “But there is no single answer for everyone. The ideal level varies depending on an individual’s risk factors. We need a personalized recommendation rather than a general rule.”
