A recent study led by Monash University has established a connection between elevated levels of high-density lipoprotein cholesterol (HDL-C), often referred to as ‘good cholesterol’, and a heightened risk of dementia, especially in individuals over the age of 75. This pivotal discovery necessitates additional research to understand the effects of high HDL-C on cognitive health.
Monash University’s research found a correlation between high HDL-C levels and an increased likelihood of dementia among older adults, underscoring the importance of further exploration in this field.
The study, led by Monash University, revealed that unusually high HDL-C levels are linked to a greater risk of dementia in the elderly population.
The researchers noted that the extremely elevated HDL-C levels associated with dementia risk in this study are rare and not influenced by diet, but are more likely indicative of a metabolic disorder.
These results could aid physicians in identifying older individuals who may be at an increased risk for dementia, particularly those who are 75 years of age or older.
Study Results in Older Demographics
Published in The Lancet Regional Health – Western Pacific, this study is among the most extensive to examine the relationship between high HDL-C levels and dementia in initially healthy seniors, primarily aged over 70, participating in the ASPREE* study.
Over an average follow-up period of 6.3 years, it was observed that participants with extremely high HDL-C levels (>80 mg/dL or >2.07 mmol/L) at the beginning of the study had a 27% increased risk of developing dementia compared to those with optimal HDL-C levels. This risk was even higher, at 42%, in participants aged 75 and older.
HDL-C levels exceeding 80 mg/dL (>2.07 mmol/L) were classified as very high. The ideal HDL-C range is 40 to 60 mg/dL (1.03–1.55 mmol/L) for men and 50 to 60 mg/dL (1.55–2.07 mmol/L) for women, which is generally beneficial for cardiovascular health.
Data on Participants
The analysis included 18,668 participants, of whom 2,709 had very high HDL-C levels at the start of the study. There were 38 cases of dementia among participants under 75 with very high levels, and 101 cases among those aged 75 or older.
Dr. Monira Hussain, a senior research fellow at Monash University School of Public Health and Preventive Medicine and the study’s lead author, emphasized the need for further investigation to understand why extremely high levels of HDL cholesterol might influence dementia risk.
Need for Additional Research
Dr. Hussain stated that the findings could enhance our understanding of dementia’s underlying mechanisms, but more research is needed.
“While HDL cholesterol is recognized as vital for heart health, this study indicates the necessity of further research to comprehend its role in brain health, particularly when HDL cholesterol levels are very high,” she explained.
She suggested that considering very high HDL cholesterol levels in dementia risk prediction models might be advantageous.
Reference: “Association of plasma high-density lipoprotein cholesterol level with risk of incident dementia: a cohort study of healthy older adults” by Sultana Monira Hussain, Catherine Robb, Andrew M. Tonkin, Paul Lacaze, Trevor T.-J. Chong, Lawrence J. Beilin, Chenglong Yu, Gerald F. Watts, Joanne Ryan, Michael E. Ernst, Zhen Zhou, Johannes T. Neumann and John J. McNeil, 29 November 2023, The Lancet Regional Health – Western Pacific.
DOI: 10.1016/j.lanwpc.2023.100963
*The Aspirin in Reducing Events in the Elderly (ASPREE) trial is a comprehensive, double-blind, placebo-controlled study, investigating the effects of daily aspirin on healthy older adults. ASPREE enrolled 16,703 participants aged 70 or older (from Australia) and 2,411 participants aged 65 or older (from the USA) between 2010 and 2014. These participants had no prior diagnosis of cardiovascular disease, dementia, physical disability, or life-threatening illness at the time of enrolment. The study now continues in its observational follow-up phase, ASPREE-XT (Extension).
Table of Contents
Frequently Asked Questions (FAQs) about HDL-C Dementia Risk
What is the key finding of the Monash University-led study?
The study discovered a significant link between high levels of HDL-C, known as ‘good cholesterol’, and an increased risk of dementia in older adults, particularly those over the age of 75.
How does high HDL-C affect dementia risk according to the study?
Participants with very high HDL-C levels (>80 mg/dL or >2.07 mmol/L) showed a 27% higher risk of dementia compared to those with optimal levels. This risk increases to 42% for participants aged 75 and older.
What does the study suggest about the relationship between HDL-C and brain health?
While HDL-C is important for cardiovascular health, the study suggests that very high levels of HDL-C might negatively impact brain health, indicating a need for further research in this area.
Where were the study’s findings published?
The findings were published in The Lancet Regional Health – Western Pacific.
What was the sample size and duration of the study?
The study analyzed 18,668 participants over an average period of 6.3 years.
Who led the research and what was the study’s main objective?
The research was led by Dr. Monira Hussain, a senior research fellow at Monash University, aiming to understand the role of very high HDL cholesterol levels in the risk of dementia.
What does the ASPREE trial, related to the study, involve?
The ASPREE (Aspirin in Reducing Events in the Elderly) trial is a double-blind, placebo-controlled study focusing on the effects of daily aspirin in healthy older people, primarily those over 70 years of age, with no prior history of cardiovascular disease, dementia, or life-threatening illness.
More about HDL-C Dementia Risk
- Monash University Research
- HDL-C and Dementia Study
- The Lancet Regional Health Publication
- ASPREE Trial Overview
- Dementia Risk Factors
4 comments
Its important research, but we shouldnt forget that HDL-C is still crucial for heart health. Balance is key, as always.
Interesting study but i’m wondering how they define ‘very high’ HDL-C levels? Need more info before we jump to conclusions.
Didn’t know Monash Uni was doing such groundbreaking work. Gotta keep an eye on what they publish next.
wow, this is really surprising! always thought good cholesterol was, well, good. guess we’re learning new things everyday.