High triglycerides, other cholesterol raise risk of stroke

People with high triglycerides and another type of cholesterol tested but not usually evaluated as part of a person's risk assessment have an increased risk of a certain type of stroke, according to research published in the December 26, 2007, online issue of Neurology, the medical journal of the American Academy of Neurology.

“LDL or ‘bad' cholesterol has been the primary target for reducing the risk of stroke, but these results show that other types of cholesterol may be more strongly linked with stroke risk,” said study author Bruce Ovbiagele, MD, of UCLA Medical Center in Los Angeles, CA, and member of the American Academy of Neurology.

The researchers analyzed the records of 1,049 people admitted to a university hospital with a stroke or mini-stroke over four years. Of those, 247 people had a large artery atherosclerotic stroke. This is a type of ischemic stroke caused by a blockage of blood flow to the brain. People with this type of stroke have blockage in the large arteries leading to the brain.

Those with high triglycerides and elevated “non-high density lipoprotein cholesterol” were more likely to have a large artery atherosclerotic stroke than those with low levels of these fats in the blood.

Those with the highest triglycerides were 2.7 times more likely to have this type of stroke than those with the lowest level. Triglycerides are fatty acids and are the most common type of fat in the blood. Those with the greatest non-high density lipoprotein cholesterol, which is neither the “good” nor the “bad” cholesterol, were 2.4 times more likely to have a large artery stroke.

“Because this type of cholesterol is included in the test that is normally ordered, and triglycerides are already reported, it would not be difficult to start paying closer attention to these factors in people at risk for large artery stroke,” Ovbiagele said.

The study found that people with high “bad” cholesterol did not have an increased risk of this type of stroke. Ovbiagele noted that it is still important to monitor bad cholesterol levels to reduce risk of heart disease and other types of stroke.