MedWire News: People who have high cholesterol levels in their early 40s are more likely to develop Alzheimer's disease in later life than their peers with low cholesterol levels, researchers have found.

The findings indicate the importance of keeping cholesterol levels under check, not only to protect against heart disease and other cardiovascular problems, but also to protect against dementia, said lead researcher Dr Alina Solomon, from the University of Kuopio in Finland.

Dr Solomon and team studied data on 9752 US men and women who underwent health evaluations between 1964 and 1973 when they were aged between 40 and 45 years.

The researchers examined the patients' medical records for the period 1994 to 2007 and found that 504 had developed Alzheimer's disease.

Analysis revealed that patients with total cholesterol levels of between 249 mg and 500 mg in middle age were 1.5 times more likely to develop Alzheimer's disease in later life than those with cholesterol levels of less than 198 mg.

People with total cholesterol levels of 221 mg to 248 milligrams faced a 1.2-fold increased risk of Alzheimer's disease compared with those with cholesterol levels of less than 198 mg.

"High mid-life cholesterol increased the risk of Alzheimer's disease regardless of midlife diabetes, high blood pressure, obesity, smoking and late-life stroke," said Dr Solomon.

She concluded: "Our findings show it would be best for both physicians and patients to attack high cholesterol levels in their 40s to reduce the risk of dementia."

The research was presented at the annual meeting of the American Academy of Neurology in Chicago, Illinois, USA.