LDL cholesterol variability is associated with declining cognitive performance in older adults, according to research findings. “Bad” LDL cholesterol has been associated with artery plaque buildup contributing to heart disease. Aside from its effects on the heart, the findings of the study suggest that LDL cholesterol could also play a negative role in cognitive function.
Based on a European study of older adults aged 70 to 82, the researchers concluded that greater fluctuations in LDL cholesterol levels translated into greater cognitive decline.
The study found for participants with the highest LDL cholesterol variability it took 2.7 seconds longer to complete a cognitive test, compared to those with the lowest variability.
Lead author Roelof Smit said, “While this might seem like a small effect, it is significant at a population level.” The link between fluctuating LDL cholesterol and declining cognitive function was present even in patients on cholesterol-lowering statins. Smit added, “Our findings suggest for the first time that it’s not just the average level of your LDL-cholesterol that is related to brain health, but also how much your levels vary from one measurement to another.”
Fluctuations in LDL cholesterol levels can occur due to diet, exercise, frequency of statin intake, along with other factors. On the other hand, these fluctuations may also indicate impaired homeostasis, which could be a result of aging or an underlying health problem.
The study involved 4,428 subjects from Scotland, Ireland, and the Netherlands, participating in the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER). All of them either had a prior vascular disease or were at a higher risk for developing one due to other risk factors like hypertension.
The researchers tested LDL cholesterol variability and cognitive function through a series of tests.
As the study was conducted in Europe, direct application of these results to the U.S. population is difficult due to differences in lifestyles.
Smit concluded, “These results add an important puzzle piece to the emerging evidence that vascular risk factors are closely related to brain health. Our study is just the first exciting step. Further studies are needed to examine whether these findings could truly influence clinical practice.”
Cholesterol and brain health
An alternative study uncovered that low cholesterol was associated with cognitive problems. Brain fog is the most common side effect of statins. In fact, some researchers have suggested that the association between statins and cognition issues is nearly 100 percent if sensitive testing methods are used.
On the other hand, patients on statins are not the only ones who experience cognitive issues. It has also been found that individuals with low cholesterol also experience cognitive problems.
The study analyzed 789 men and 1,105 women, examining the relationship between cholesterol and cognitive performance. The researchers found that those with the lowest cholesterol levels performed the worst on cognitive tests, compared to subjects with the highest cholesterol. Study lead author Dr. Penelope Elias said, “It is not entirely surprising that lower cholesterol levels were associated with moderately lower levels of cognitive function given that cholesterol is important in brain function. Naturally low levels of cholesterol and lowered levels of cholesterol may have very different ramifications for cognitive function.”
Other studies have also shown low serum levels due to statin use are associated with cognitive dysfunction.