Cited by 346Autism Spectrum Disorder ResearchGenetics and Neurodevelopmental DisordersNeuroendocrine regulation and behavior

Blood serotonin levels in autism spectrum disorder: A systematic review and meta-analysis

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Gabriele, Stefano, Sacco, Roberto, Persico, Antonio M.·2014·European Neuropsychopharmacology

Abstract

Elevated blood serotonin (5-HT) levels were the first biomarker identified in autism research. Many studies have contrasted blood 5-HT levels in autistic patients and controls, but different measurement protocols, technologies, and biomaterials have been used through the years. We performed a systematic review and meta-analysis to provide an overall estimate of effect size and between-study heterogeneity, while verifying whether and to what extent different methodological approaches influence the strength of this association. Our literature search strategy identified 551 papers, from which 22 studies providing patient and control blood 5-HT values were selected for meta-analysis. Significantly higher 5-HT levels in autistic patients compared to controls were recorded both in whole blood (WB) [O.R.=4.6; (3.1-5.2); P=1.0×10(-12]), and in platelet-rich plasma (PRP) [O.R.=2.6 (1.8-3.9); P=2.7×10(-7)]. Predictably, studies measuring 5-HT levels in platelet-poor plasma (PPP) yielded no significant group difference [O.R.=0.54 (0.2-2-0); P=0.36]. Altogether, elevated 5-HT blood levels were recorded in 28.3% in WB and 22.5% in PRP samples of autistic individuals, as reported in 15 and 4 studies, respectively. Studies employing HPLC vs fluorometric assays yield similar cumulative effect sizes, but the former display much lower variability. In summary, despite some limitations mainly due to small study sample sizes, our results significantly reinforce the reliability of elevated 5-HT blood levels as a biomarker in ASD, providing practical indications potentially useful for its inclusion in multi-marker diagnostic panels for clinical use.

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Crossref · 10.1016/j.euroneuro.2014.02.004

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Authors
Gabriele, S., Sacco, R., & Persico, A. M.
Affiliations
Università Campus Bio-Medico (IT)
Corresponding author
Persico, Antonio M.
Venue
European Neuropsychopharmacology
Publisher
Elsevier BV
Published
2014-06
Volume
24
Issue
6
Pages
919-929
ISSN
0924-977X (ISSN-L)
OpenAlex
W2158197814
Cited by
346
References
75
Citations by year
2026: 21 · 2025: 18 · 2024: 36 · 2023: 43 · 2022: 31 · 2021: 40 · 2020: 27 · 2019: 30 · 2018: 26 · 2017: 22 · 2016: 17 · 2015: 20 · 2014: 14 · 2013: 1
FWCI
2.36
Type
journal article
Language
en
Open access
Locations
  • European Neuropsychopharmacology (publishedVersion)
  • PubMed (publishedVersion)
  • IRIS UNIMORE (University of Modena and Reggio Emilia) (submittedVersion, cc-by)
Topics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Autism Spectrum Disorder Research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetics and Neurodevelopmental Disorders
  • Social Sciences › Psychology › Social Psychology › Neuroendocrine regulation and behavior
Keywords
autism spectrum disorder, blood serotonin, serotonin, biomarkers, platelet-rich plasma, whole blood, platelet-poor plasma, diagnostic panel, methodological heterogeneity
MeSH terms
Blood Chemical Analysis, Child Development Disorders, Pervasive, Humans, Serotonin, Biomarkers, Platelet-Rich Plasma, Endophenotypes

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