{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T13:18:20Z","timestamp":1788873500655,"version":"build-2803163510"},"reference-count":47,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,18]],"date-time":"2023-04-18T00:00:00Z","timestamp":1681776000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Genting TauRx Diagnostic Centre, Malaysia"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Objectives: With the development of new technologies capable of detecting low concentrations of Alzheimer\u2019s disease (AD) relevant biomarkers, the idea of a blood-based diagnosis of AD is nearing reality. This study aims to consider the evidence of total and phosphorylated tau as blood-based biomarkers for mild cognitive impairment (MCI) and AD when compared to healthy controls. Methods: Studies published between 1 January 2012 and 1 May 2021 (Embase and MEDLINE databases) measuring plasma\/serum levels of tau in AD, MCI, and control cohorts were screened for eligibility, including quality and bias assessment via a modified QUADAS. The meta-analyses comprised 48 studies assessing total tau (t-tau), tau phosphorylated at threonine 181 (p-tau181), and tau phosphorylated at threonine 217 (p-tau217), comparing the ratio of biomarker concentrations in MCI, AD, and cognitively unimpaired (CU) controls. Results: Plasma\/serum p-tau181 (mean effect size, 95% CI, 2.02 (1.76\u20132.27)) and t-tau (mean effect size, 95% CI, 1.77 (1.49\u20132.04)) were elevated in AD study participants compared to controls. Plasma\/serum p-tau181 (mean effect size, 95% CI, 1.34 (1.20\u20131.49)) and t-tau (mean effect size, 95% CI, 1.47 (1.26\u20131.67)) were also elevated with moderate effect size in MCI study participants compared to controls. p-tau217 was also assessed, albeit in a small number of eligible studies, for AD vs. CU (mean effect size, 95% CI, 1.89 (1.86\u20131.92)) and for MCI vs. CU groups (mean effect size, 95% CI, 4.16 (3.61\u20134.71)). Conclusions: This paper highlights the growing evidence that blood-based tau biomarkers have early diagnostic utility for Alzheimer\u2019s disease. Registration: PROSPERO No. CRD42020209482.<\/jats:p>","DOI":"10.3390\/cells12081184","type":"journal-article","created":{"date-parts":[[2023,4,19]],"date-time":"2023-04-19T01:09:22Z","timestamp":1681866562000},"page":"1184","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":37,"title":["Utility of Blood-Based Tau Biomarkers for Mild Cognitive Impairment and Alzheimer\u2019s Disease: Systematic Review and Meta-Analysis"],"prefix":"10.3390","volume":"12","author":[{"given":"Alex","family":"Zabala-Findlay","sequence":"first","affiliation":[{"name":"Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK"},{"name":"Scottish Biologics Facility, University of Aberdeen, Aberdeen AB25 2ZP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3722-4476","authenticated-orcid":false,"given":"Lewis K.","family":"Penny","sequence":"additional","affiliation":[{"name":"Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK"},{"name":"Scottish Biologics Facility, University of Aberdeen, Aberdeen AB25 2ZP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard A.","family":"Lofthouse","sequence":"additional","affiliation":[{"name":"Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK"},{"name":"Scottish Biologics Facility, University of Aberdeen, Aberdeen AB25 2ZP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew J.","family":"Porter","sequence":"additional","affiliation":[{"name":"Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK"},{"name":"Scottish Biologics Facility, University of Aberdeen, Aberdeen AB25 2ZP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Soumya","family":"Palliyil","sequence":"additional","affiliation":[{"name":"Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK"},{"name":"Scottish Biologics Facility, University of Aberdeen, Aberdeen AB25 2ZP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2250-3920","authenticated-orcid":false,"given":"Charles R.","family":"Harrington","sequence":"additional","affiliation":[{"name":"Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK"},{"name":"GT Diagnostics, Aberdeen AB24 5RP, UK"},{"name":"TauRx Therapeutics Ltd., Aberdeen AB24 5RP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claude M.","family":"Wischik","sequence":"additional","affiliation":[{"name":"Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK"},{"name":"GT Diagnostics, Aberdeen AB24 5RP, UK"},{"name":"TauRx Therapeutics Ltd., Aberdeen AB24 5RP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammad","family":"Arastoo","sequence":"additional","affiliation":[{"name":"Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK"},{"name":"Scottish Biologics Facility, University of Aberdeen, Aberdeen AB25 2ZP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,18]]},"reference":[{"key":"ref_1","unstructured":"Patterson, C. 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