Plasma phosphorylated tau 181 in relation to Alzheimer’s prevalence and cognition in the Thai community

• Published in: Alzheimer's & dementia Vol. 19; no. S14
• Main Authors: Hemachudha, Pasin, Thanapornsangsuth, Poosanu, Saraya, Abhinbhen Wasontiwong, Luechaipanit, Watayuth, Hemachudha, Thiravat
• Format: Journal Article
• Language: English
• Published: 01-12-2023
• ISSN: 1552-5260; 1552-5279
• DOI: 10.1002/alz.075993

Background
The identification of biomarkers for Alzheimer’s disease (AD) in blood samples has the potential to facilitate early diagnosis and improve the accuracy of AD diagnosis. Plasma phosphorylated tau (p‐tau) is a promising biomarker for AD; however, its utility in estimating the prevalence of AD and screening for cognitive impairment in non‐demented populations has yet to be explored in Thailand.
Method
The study recruited 110 non‐demented participants over the age of 40 from the family members of patients attending a neurology clinic. Plasma p‐tau 181 levels were measured, and AD prevalence was estimated using a pre‐defined cut‐off derived from an independent cohort with biomarker‐defined AD status according to the current framework (Jack et. al., 2018). The correlation between plasma p‐tau 181 levels and. neuropsychological data were also evaluated.
Result
The median age of participants was 66 years, and the median mini‐mental state examination score was 29. The estimated prevalence of AD was 20.0% (95% CI 13.6‐28.4) in preclinical and mild cognitive impairment patients when using p‐tau as a biomarker, which was lower than the prevalence estimated using amyloid abnormalities of 30.1% (95% CI 29.2‐31.1)(Jansen et. al., 2022) (X
2 [N = 8944] = 5.28, p = .022). Plasma p‐tau 181 levels also showed a negative correlation with neurocognitive test scores (Rho = ‐0.24, P .013).
Conclusion
The results of this study suggest that plasma p‐tau 181 is a promising biomarker for the estimation of AD prevalence in non‐demented populations in Thailand and may represent those at risk of clinical onset. However, further studies are needed to investigate its utility in risk stratification, public health preparedness, and cognitive performance assessment.