Older adults with higher triglycerides may have a lower risk of dementia as well as slower cognitive decline and memory loss over time compared to those with lower levels. That’s according to new research published in the October 25, 2023, online issue of Neurology®, the medical journal of the American Academy of Neurology (REF 1).
The link between triglycerides and lower risk of dementia
The liver stores fatty acids as triglycerides, which are the most common type of fat in our bodies. We also get them directly from the carbs and saturated fat in our diets. What the body doesn’t use for energy production is stored in fat cells.
Triglyceride levels are classified into the following categories for adults:
Normal: Less than 150 milligrams per deciliter (mg/dL), or less than 1.7 millimoles per liter (mmol/L)
Borderline high: 150 to 199 mg/dL (1.8 to 2.2 mmol/L)
High: 200 to 499 mg/dL (2.3 to 5.6 mmol/L)
Very high: 500 mg/dL or above (5.7 mmol/L or above)
The Study
Researchers used healthcare data to identify 18,294 people with an average age of 75 who did not have a prior diagnosis of Alzheimer’s disease or dementia. Participants were followed for an average of six years. During that time, 823 people developed dementia.
Researchers looked at participants’ total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL) and high-density lipoprotein cholesterol (HDL) each year of the study. They then divided participants into four groups based on fasting triglyceride levels.
Of the total group, average triglycerides were 106 milligrams per deciliter (mg/dL). For adults, anything below 150 mg/dL is considered a normal or healthy level.
What did the study find?
After adjusting for variables that could affect risk of dementia (including education and cholesterol-lowering treatments), researchers found that with every doubling of triglyceride levels there was an 18% lower risk of developing dementia.
When comparing the first group (which had the lowest triglycerides levels, less than 62 mg/dL), with the second group (levels of 63 to 106 mg/dL), they found that the second group was 15% less likely to develop dementia.
The third group (whose levels were 107 to 186 mg/dL) were 24% less likely to develop dementia than the first group.
The fourth group had levels of 187 mg/dL or higher. They were 36% less likely to develop dementia than the first group.
Here are the actual numbers:
- Of the 1,416 people in the lowest triglyceride group, 82 people, or 6%, developed dementia.
- Of the 7,449 people in the second group, 358 people, or 5%, developed dementia.
- Of the 7,312 people in the third group, 310, or 4%, developed dementia.
- Of the 2,117 people in the fourth group, 73 people, or 3%, developed dementia.
The research were consistent
The researchers validated their results through another dataset comprised of 68,200 older people from the UK. Among them, 2,778 people developed dementia over an average time of 12 years. The results were consistent: a 17% decreased risk of dementia with every doubling of triglycerides levels.
They also found that higher triglycerides were associated with slower decline in something called “composite cognition”. This is a combined result from tests of global function, psychomotor speed, language, executive function, and memory over time.
Do high levels of triglycerides prevent dementia?
The researchers made it clear that while the study found a link, it does not prove that higher levels of triglycerides prevent dementia. In a piece published by United Press International, they shared further insights.
Zhen Zhou, who led the study, suggested that lower triglycerides may be related to weight loss, health conditions, or frailty; those with higher triglycerides may be better nourished and/or have fewer health conditions.
In addition, the study only looked at those 65 years and older; it’s possible that the results might differ with age. For example, high triglycerides in middle-aged adults may increase health risks, including that of heart disease. By implication, their findings could not be generalized to other age groups.
Zhou and colleagues concluded by saying that future studies are needed to investigate whether specific components within triglycerides may promote better cognitive function. If so, this would open the door to new preventive strategies.
Source: AAN – https://www.aan.com/PressRoom/Home/PressRelease/5122 – Please note that content from the press release may be edited for style and length
References
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Association Between Triglycerides and Risk of Dementia in Community-Dwelling Older Adults: A Prospective Cohort Study. Zhen Zhou, Joanne Ryan, Andrew M Tonkin, Sophia Zoungas, Paul Lacaze, Rory Wolfe, Suzanne G Orchard, Anne M Murray, John J Mcneil, Chenglong Yu, Gerald F Watts, Sultana Monira Hussain, Lawrence J Beilin, Michael Ernst, Nigel Stocks, Robyn L Woods, Chao Zhu, Christopher Reid, Raj C Shah, Trevor T Chong, Ajay Sood, Kerry M Sheets, Mark Nelson, Neurology Oct 2023, 10.1212/WNL.0000000000207923; DOI: 10.1212/WNL.0000000000207923
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United Press International. Author Amy Norton, Health Day News – https://www.upi.com/Health_News/2023/10/26/blood-triglycerides-dementia/7071698325737/
