While we all know that ‘bad’ cholesterol is no good, a study has found that roller coaster levels of it may lead to poorer mental performance in older adults, a study has found.
In a study of European adults age 70 to 82 years old, researchers found that greater fluctuations in low-density lipoprotein cholesterol (LDL), or “bad” cholesterol, are associated with lower cognitive performance.
More LDL variability was also associated with lower brain blood flow and bright areas showing up on brain scans which have been linked to blood vessel dysfunction.
The findings are reported in the American Heart Association journal Circulation.
The researchers, led by Dr Roelof Smit at Leiden University Medical Center in the Netherlands, studied a total of 4428 people aged 70 to 82 from Scotland, Ireland and the Netherlands. All either had pre-existing artery disease or were at high risk of developing the condition. Those enrolled in the study were taking a statin, a medication that lowers LDL cholesterol.
Previous studies hinted that LDL levels influence stroke as well as heart disease risk, so Dr Smit and his colleagues wanted to investigate whether they have an effect on cognitive functions like attention, information processing and memory. They only analysed people who had been taking the statin for at least three months in order to avoid any bias caused by the sudden change in LDL levels by the drug, and compared them to people who didn’t take the drug.
The study could not isolate why people’s LDL levels fluctuated, but changes in diet and exercise could be important factors to consider. Changes in the body’s ability to maintain a proper balance of cholesterol levels could also be a factor, since with age, this equilibrium could be disrupted. The statin medications were unlikely to be a major contributor since they remained constant, says Dr Smit.
Dr Anthony Komaroff of Harvard also says, “People who have high levels of LDL (bad) cholesterol or blood pressure, or who are obese, have a higher risk of Alzheimer’s disease and that can be fixed with medicines, exercise, and proper diet.”