California [US], December 1 (ANI): An increased risk of dementia in older persons has been linked to abnormally high levels of HDL-C, also referred to as good cholesterol, according to a Monash University-led study.
Extremely high levels of HDL-C associated with dementia risk were unusual, unrelated to food, and more likely to be indicative of a metabolic condition, according to researchers.
The results could aid medical professionals in identifying an elderly patient population that may be susceptible to dementia, especially those 75 years of age and above.
One of the largest investigations on the relationship between elevated HDL-C levels and dementia among initially healthy older adults, primarily over 70, who were included in the ASPREE* trial, was published in The Lancet Regional Health – Western Pacific.
Over an average of 6.3 years, participants with very high HDL-C (80 mg/dL) at study entry were observed to have a 27 per cent higher risk of dementia compared to participants with optimal HDL-C levels, while those aged 75 years and older also showed a 42 per cent increased risk compared to those with optimal levels.
Very high HDL-C levels were categorised as 80 mg/dL or above. The optimal level of HDL-C of 40 to 60 mg/dL for men and 50 to 60 mg/dL for women was generally beneficial for heart health.
Among 18,668 participants included in this analysis, 2709 had very high HDL-C at study entry, with 38 incidents of dementia in those aged less than 75 years with very high levels, and 101 in those aged 75 and more with very high levels.
First author and Monash University School of Public Health and Preventive Medicine senior research fellow Dr Monira Hussain said that further research was needed to explain why a very high HDL cholesterol level appeared to affect the risk of dementia.
Dr Hussain said these study findings could help improve our understanding of the mechanisms behind dementia, but more research was required.
“While we know HDL cholesterol is important for cardiovascular health, this study suggests that we need further research to understand the role of very high HDL cholesterol in the context of brain health,” she said.
“It may be beneficial to consider very high HDL cholesterol levels in prediction algorithms for dementia risk.”
Key takeaways:
- Study Focus: Examined the link between high-density lipoprotein cholesterol (HDL-C) levels and dementia risk in older adults.
- Background: HDL-C, known as “good cholesterol,” traditionally associated with lower cardiovascular disease risk.
- The Results: A significant association was found between very high HDL-C levels and an increased risk of dementia, especially in those aged 75 and older.
- Challenging Previous Beliefs: This study challenges the traditional view that higher HDL-C levels are universally beneficial.
- Public Health Implications: Suggests a need for re-evaluating HDL-C level guidelines, especially for older adults.
Key sources of ‘good cholesterol’
Fatty fish:
Fatty fish, such as salmon, mackerel, sardines, herring, and tuna, are rich in omega-3 fatty acids, which have been shown to raise HDL levels. Omega-3 fatty acids also help to lower LDL cholesterol and triglycerides, both of which are considered “bad” cholesterol.
Olive oil:
Olive oil is a good source of monounsaturated fats, which can help to raise HDL levels. Monounsaturated fats can also help to lower LDL cholesterol and triglycerides.
Nuts and seeds:
Nuts and seeds, such as almonds, walnuts, pistachios, chia seeds, and flaxseeds, are good sources of fiber and healthy fats, both of which can help to raise HDL levels.
Avocados:
Avocados are a good source of monounsaturated fats and fiber, both of which can help to raise HDL levels.
Whole grains:
Whole grains, such as oats, brown rice, and quinoa, are a good source of fiber, which can help to lower LDL cholesterol. Whole grains can also help to raise HDL levels.
Legumes:
Legumes, such as beans, lentils, and peas, are a good source of fiber and protein, both of which can help to lower LDL cholesterol. Legumes can also help to raise HDL levels.
In addition to eating a healthy diet, there are other lifestyle changes that can help to raise HDL levels, such as regular exercise, quitting smoking, and maintaining a healthy weight.
