Study links low LDL-C levels to reduced risk of dementia

People with low levels of low-density lipoprotein cholesterol (LDL-C) in their blood have a lower risk of dementia, including lower risk of Alzheimer's disease related dementia, shows a study published online today in the Journal of Neurology Neurosurgery & Psychiatry. Use of statins conveyed an additional protective effect for people with low LDL-C, specifically those with blood levels less than 1.8 mmol/L (130mg/dL), and matched individuals in each group into 108,980 matched pairs.

Analysis of subsequent diagnoses of dementia showed that LDL-C levels below 1.8 mmol/L (130mg/dL). The protective effect against cognitive decline lessened at lower LDL-C levels and eventually disappeared entirely.



At LDL-C levels below 1.4 mmol/L (130mg/dL), and when LDL-C levels fell below 0.8 mmol/L (<30mg/dL) the risk reductions disappeared.

Related Stories Blood test offers insight into Alzheimer's stage and severity Traditional Chinese medicine targets cholesterol metabolism for cancer treatment A pecan a day keeps bad cholesterol away Statin use conferred additional protection against dementia in the presence of low LDL-C levels. Among people with LDL-C levels below 1.8 mmol/L (<70mg/dL), statin use was associated with a 13% reduction in all cause dementia risk and a 12% decrease in risk of Alzheimer's disease related dementia compared with non-users.

This is an observational study, and as such, no firm conclusions can be drawn about cause and effect. The authors also acknowledge that the study has some limitations including the potential for unmeasured confounding factors because of its retrospective design, possible underreporting of dementia cases due to variations in diagnostic accuracy between hospitals, and the focus on baseline LDL-C levels when lipid profiles could change over time. Nevertheless, the authors conclude: "Low LDL-C levels (<70 mg/dL (<1.

8 mmol/L)) are significantly associated with a reduced risk of dementia, including Alzheimer's disease related dementia, with statin therapy providing additional protective effects." They add: "These findings underscore the crucial role of managing LDL-C in lowering dementia risk." BMJ Group DOI: 10.

1136/jnnp-2024-334708.