High cholesterol levels dont predict stroke risk in women
But the risk of stroke is found among men who have twice the average level of cholesterol, according to researchers at the Copenhagen University Hospital.
The 33-year-long study, published in the journal Annals of Neurology, however found a link, in both men and women, between the risk of stroke and non-fasting triglycerides, a different type of fat in the blood.
"Interestingly, current guidelines on stroke prevention have recommendations on desirable cholesterol levels, but not on non-fasting triglycerides," said lead study author Dr Marianne Benn from Copenhagen University Hospital.
"Our study was the first to examine how the risk of stroke for very high levels of non-fasting triglycerides compared with very high cholesterol levels in the general population."
According to the World Health Organisation, cardiovascular diseases are the number one cause of death — responsible for an estimated 17.1 million deaths worldwide, with 5.7 million due to stroke.
The American Stroke Association states that stroke is the third leading cause of death in the US and 87 per cent of all cases are attributed to ischemic stroke, occurring when the supply of blood to the brain is obstructed.
The obstruction or blockage is typically caused by the build-up of fatty deposits inside blood vessels, called atherosclerosis.
Medical evidence suggests that elevated non-fasting triglycerides are markers of elevated levels of lipoprotein remnants, particles similar to low density lipoprotein (LDL), or bad cholesterol, both of which are thought to contribute to plaque build-up.
For the study, the Danish team followed 7,579 women and 6,372 men who were enrolled in the Copenhagen City Heart Study, all of whom were white and of Danish decent. Participants had non-fasting triglycerides and cholesterol measurements taken at baseline (1976-1978) and were followed for up to 33 years.
A diagnosis of ischemic stroke was made when focal neurological symptoms lasted more than 24 hours. During the follow-up period, 837 women and 837 men developed ischemic stroke.
Results confirmed in both women and men, increasing levels of non-fasting triglycerides associated with increased risk of ischemic stroke.