BackgroundAlzheimer's disease (AD) is the most common form of dementia, marked by progressive cognitive decline. Low-density lipoprotein cholesterol (LDL-C) has been implicated in AD pathology, but fi Show more
BackgroundAlzheimer's disease (AD) is the most common form of dementia, marked by progressive cognitive decline. Low-density lipoprotein cholesterol (LDL-C) has been implicated in AD pathology, but findings remain inconsistent. Apolipoprotein E4 (APOE4) status and sex may contribute to this variability.ObjectiveTo examine how LDL-C association with neurodegeneration in AD patients, differ according to APOE4 status and gender.MethodsWe stratified 106 AD patients by APOE4 status and sex into four subgroups: male APOE4+, female APOE4+, male APOE4-, and female APOE4-. Longitudinal cortical thickness changes were assessed using magnetic resonance imaging (MRI). We examined the association between LDL-C levels and cortical thinning within each subgroup.ResultsIn APOE4-positive females, higher LDL-C levels were significantly associated with accelerated cortical thinning in several regions, including the parahippocampal (ฮฒโ=โ-0.0075, pโ=โ0.017), medial orbitofrontal (ฮฒโ=โ-0.0025, pโ=โ0.028), fusiform (ฮฒโ=โ-0.0047, pโ=โ0.034), posterior cingulate (ฮฒโ=โ-0.0097, pโ=โ0.006), and inferior temporal cortices (ฮฒโ=โ-0.0085, pโ=โ0.019). This subgroup also showed a significant association between LDL-C and MMSE decline (ฮฒโ=โ-1.409, pโ=โ0.014) as well as longitudinal increases in cerebrospinal fluid phosphorylated tau181 (ฮฒโ=โ0.014, pโ=โ0.039). These effects were not observed in other subgroups.ConclusionsElevated LDL-C is associated with increased neurodegeneration and cognitive decline in female AD patients carrying the APOE4 allele. These exploratory findings highlight a subgroup-specific vulnerability to lipid-related neurodegeneration in AD and underscore the importance of considering both sex and genetic background in future studies. Show less