Low levels of cholesterol may reduce the risk of heart disease, but it could also increase the risk of hemorrhagic stroke, according to a new study.
For nine years, researchers from Penn State carefully studied the link between low-density lipoprotein cholesterol (LDL)and hemorrhagic stroke - a type of stroke caused when blood vessels burst in the brain.
Xiang Gao, an associate professor of nutritional sciences and director of the Nutritional Epidemiology Lab at Penn State, believes the findings can help provide personalized recommendations to maintain the right cholesterol levels. "As is true with many things in nutrition, moderation and balance is key when deciding the optimal target level of LDL cholesterol," Gao told a news portal. Adding, "You can't go to either extreme—too high or too low. And if you're at a high risk for hemorrhagic stroke due to family history or risk factors like high blood pressure and heavy alcohol drinking, you may want to be extra careful about LDL cholesterol levels."
Even though previous studies have found a link between the two, further investigation is needed to better understand the relationship. "For our study, we wanted to expand the scope of knowledge in this area by investigating the issue prospectively in a large cohort with multiple LDL cholesterol measurements to capture variation over time," Chaoran Ma, a nutritional sciences graduate student at Penn State, told a news portal.
At the start of the study, 96,043 people were chosen to participate in the research. None of the participants had a history of cancer, heart attack or stroke. Each participants'LDL cholesterol levels were measured once a year. Medical records revealed incidents of hemorrhagic stroke. The results showed the risk of hemorrhagic stroke was high for participants with LDL cholesterol levels below 70 mg/dL. The findings were the same when factors like age, sex, blood pressure and medication were taken into consideration.
"Traditionally, an LDL cholesterol level of more than 100 mg/dL had been considered as optimal for the general population and lower in individuals at elevated risk of heart disease," Gao told a news portal. Adding, "We observed that the risk of hemorrhagic stroke increased in individuals with LDL cholesterol levels below 70 mg/dL. This observation, if confirmed, has important implications for treatment targets."
Researchers hope the findings urge health care professionals to refine guidelines. "The results were based on a large community-based study, which is an advantage because it focused on healthy people in a non-clinical setting," Ma told a news portal.
The study's findings were originally published in Neurology.
