Neurology: Lowering "good cholesterol" can increase the risk of Parkinson's disease by 60%

High-density lipoprotein cholesterol (HDL-C) is mainly synthesized in the liver and is an anti-atherosclerotic lipoprotein.

Numerous previous studies have shown that there is an inverse relationship between a decrease in high-density lipoprotein cholesterol and an increased risk of coronary heart disease and myocardial infarction.

Therefore, it is generally believed that the level of its plasma content is negatively related to the risk of cardiovascular disease.

HDL-C is almost recognized as good cholesterol.
This is in contrast to the so-called "bad" cholesterol, low-density lipoprotein cholesterol (LDL-C), which causes cholesterol to accumulate in the arteries and increases the risk of cardiovascular disease.
.

However, this view has been challenged in recent years.

There have been several large-scale clinical studies that tested HDL-C to reduce the risk of cardiovascular disease, but none of them proved to have a preventive effect on coronary heart disease.

Therefore, the 2018 American Heart Association Scientific Conference (AHA 2018) released a new version of cholesterol management guidelines, which emphasized more individualized risk assessment and selection of new cholesterol-lowering drugs for people at high risk of atherosclerotic cardiovascular disease.

Recently, researchers from the Korea University School of Medicine discovered that not only HDL-C levels, but HDL-C variants are closely related to the risk of the most common neurodegenerative disease, Parkinson’s disease.

The results were published in the latest "Neurology" (Neurology) magazine.

The researchers conducted a nationwide, population-based cohort study that included 382,391 participants aged ≥65 years.

All participants received at least 3 health examinations provided by the Korean National Health Insurance System between 2008 and 2013, and were followed up until 2017.

HDL-C variability was assessed using 3 indexes including variability independent of the mean (VIM).

A multivariate adjusted Cox proportional hazard regression analysis was performed.

After excluding patients with pre-existing Parkinson's disease, a total of 380,404 participants completed the follow-up.

The results showed that 2,733 people were newly diagnosed with PD during the 5-year median follow-up period.

Compared with the highest quartile group, the lowest quartile of baseline HDL-C and average HDL-C increased the incidence of PD by 20% and 16%, respectively (adjusted HR=1.
20; 95% CI: 1.
08-1.
34; HR=1.
16; 95%CI, 1.
04-1.
30).

Compared with the lowest quartile group, the highest quartile group of HDL-C variability (VIM) increased the incidence of PD by 19% (HR=1.
19; 95% CI, 1.
06-1.
33).

Among them, the lowest quartile group of baseline HDL-C and the highest quartile group of HDL-C variability had the highest risk of PD, and the incidence increased by 60% (HR=1.
6; 95% CI, 1.
31-1.
96).

The study suggests that lower HDL-C levels and greater HDL-C variability are associated with a higher incidence of PD.

For this reason, as far as Parkinson's disease is concerned, the higher the "good cholesterol", the better.

Reference: Association of High-Density Lipoprotein Cholesterol Variability and the Risk of Developing Parkinson Disease.
Neurology Mar 2021, 96 (10) e1391-e1401; DOI: https://doi.
org/10.
1212/WNL.
0000000000011553