Summary
| Direction in Long COVID | ↑ Elevated — higher than in the comparison group |
|---|---|
| Category | Neurological |
| Also described as | Glial fibrillary acidic protein |
| Compared against | HC (healthy controls) |
| Associated symptoms | Neurological LC, astrocyte activation |
| Test type | Blood test (serum / plasma / whole blood) |
| Source | Lai et al. 2023 — doi:10.3389/fmed.2023.1085988 |
| Condition atlas | Long COVID Biomarker Atlas |
Other conditions where GFAP is reported
- GFAP in Multiple Sclerosis — ↑ elevated vs progressive MS vs healthy/non-progressive
See the cross-condition hub: GFAP across conditions.
Trials, interventions and tests
In clinical-trial registrations this marker maps to the outcome term Glial Fibrillary Acidic Protein (GFAP) (1 registered trials use a matching outcome measure).
Clinical trials using GFAP as an outcome
- NCT07278206: Brain Stimulation in Long COVID (Recruiting)
Outcome measure: Glial Fibrillary Acidic Protein (GFAP)
Interventions studied alongside this marker
Hypothesis-generating links from trial outcome usage and literature co-occurrence. Not treatment recommendations.
- Repetitive Transcranial Magnetic Stimulation — 1 trial, 6 PubMed co-citations
e.g. Repetitive transcranial magnetic stimulation suppresses glia-associated neuroinflammation and promotes…
Related Neurological markers in Long COVID
Full list: Long COVID Biomarker Atlas.
Frequently asked questions
Is GFAP high or low in Long COVID?
Elevated. Studies summarised in the OSMF atlas report higher GFAP in Long COVID than in healthy controls. Source: Lai et al. 2023.
What symptoms is GFAP associated with in Long COVID?
The cited literature associates this marker with Neurological LC, astrocyte activation. These are population-level associations and do not mean the marker causes the symptoms.
Which test measures GFAP?
It is measured as a blood test (serum / plasma / whole blood). Many of the cited studies used research-grade assays, so clinical availability may vary.
Is one abnormal GFAP result diagnostic of Long COVID?
No. No single biomarker is diagnostic of Long COVID. GFAP findings come from group comparisons, overlap considerably between patients and controls, and vary with study design, timing and comparison group. A result should be interpreted by a clinician alongside symptoms, history and other tests.
Is GFAP specific to Long COVID?
No. The same marker is also reported in Multiple Sclerosis in this atlas, so it reflects shared biology (for example inflammation or vascular stress) rather than a condition-specific signature.
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Last reviewed: 2026-06-29 · Page generated from long-covid.json · Browse: Long COVID atlas · Biomarker Index · All marker pages
Disclaimer: This page is an educational synthesis of published, peer-reviewed research and is not medical advice. Biomarker findings vary across studies with case definitions, comparison groups, timing and assay methods. Direction of change reflects the predominant finding in the cited source and does not establish a diagnostic threshold. Discuss any test result with a qualified clinician.