Tau in dementia with Lewy bodies

Area of Science:

• Neurology
• Neuroimaging
• Biomarker Discovery

Background:

• Neurofibrillary tangles, a hallmark of Alzheimer's disease, are found in some dementia with Lewy bodies (DLB) cases and may worsen cognitive decline.
• Advances in Alzheimer's disease biomarkers include second-generation tau positron emission tomography (PET) and plasma detection of phosphorylated tau at threonine 181 (p-tau181).

Purpose of the Study:

• To investigate the presence and implications of tau pathology in individuals with dementia with Lewy bodies.
• To evaluate the utility of second-generation tau PET imaging and plasma p-tau181 as biomarkers in DLB.

Main Methods:

• Twenty-seven participants with probable DLB underwent PET imaging using ¹⁸F-MK6240 and ¹⁸F-NAV4694 tracers.
• Plasma p-tau181 levels were quantified using Simoa technology.

Main Results:

• 18.5% of DLB participants exhibited abnormal tau PET scans.
• Plasma p-tau181 concentrations positively correlated with temporal tau deposition (ρ = 0.46) and predicted abnormal tau PET.
• Plasma p-tau181 also correlated with amyloid-beta PET binding (ρ = 0.68) and predicted abnormal amyloid-beta PET.

Conclusions:

• Tau pathology is a frequent co-occurring condition in dementia with Lewy bodies.
• Plasma p-tau181 may serve as a valuable blood-based marker for identifying comorbid Alzheimer's disease-related pathologies in DLB.
• Further large-scale longitudinal studies are required to elucidate the clinical significance of tau in DLB.