Background: Alzheimer's disease (AD) is the most common cause of dementia, accounting for 65-70% of all dementia cases.
Objective: We performed a systematic review and meta-analysis to estimate the accuracy of cerebrospinal fluid Aβ1-42 for the diagnosis of AD. A comprehensive search of the Cochrane Library, MEDLINE, LILACS, Grey literature, and EMBASE was performed for papers published from January 1990 to August 2013. The following Medical Subject Headings (MeSH) terms were searched: "Alzheimer disease" or "AD" and "amyloid-β" or "Aβ1-42".
Methods: We included case-control and cross-sectional studies, prospective or retrospective, that evaluated Aβ1-42 levels in AD. Statistical analysis was performed using REVMAN 5.2, Meta Disc, and Stata 11.0.
Results: A total of 804 citations were identified by the search strategy and 41 studies were included. Meta-analysis showed a sensitivity of 84.3% (95% CI: 85.6%-81%) and specificity of 79.4% (95% CI: 77.6%-81.1%). The diagnostic odds ratio was 28.9 (95% CI: 21.2-39.5).
Conclusion: Our study demonstrated that Aβ1-42 can discriminate AD from controls with good sensitivity and specificity.
Keywords: Alzheimer's disease; Aβ$_{1-42}$; meta-analyses; systematic review.