We know that high-density lipoprotein (HDL) is good and high amounts helps offset high amounts of low-density lipoprotein (LDL). But … very high levels of HDL may be associated with increased risk of dementia, say researchers in a new study.
According to the researchers this is one of the largest studies of elevated HDL-C levels and dementia in initially healthy older people aged mostly over 70, enrolled in the ASPREE study. The Aspirin in Reducing Events in the Elderly (ASPREE) trial is a double-blind, randomized, placebo-controlled trial of daily aspirin in healthy older people.
Over an average 6.3 years, participants with very high HDL-C (>80 mg/dL or >2.07 mmol/L) at study entry were observed to have a 27 percent higher risk of dementia compared to participants with optimal HDL-C levels, while those aged 75 years and older also showed a 42 percent increased risk compared to those with optimal levels.
Very high HDL-C levels were categorized as 80 mg/dL (>2.07 mmol/L) or above.
The optimal level of HDL-C of 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 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.
Lead author Dr. Monira Hussain said that 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.”
For more information, visit www.thelancet.com/journals/lanwpc/article/PIIS2666-6065(23)00281-X/fulltext.