Multiple sclerosis does not always progress in an obvious way. In some patients, the disease may continue for a long time without significant relapses, while difficulties with walking, coordination, memory, or performing routine daily tasks gradually develop.
This type of hidden progression is considered one of the most challenging issues in modern neurology. An international group of researchers, with the participation of specialists from University Hospital Basel, studied a blood test that could help doctors detect such changes earlier in the future.
The biomarker in question is GFAP — glial fibrillary acidic protein.
Why the Absence of Relapses Is Not Enough
Modern treatment for multiple sclerosis can significantly reduce the frequency of relapses and decrease the inflammatory activity of the disease. If a patient experiences no new relapses for a long period, this is usually considered a positive outcome.
However, the absence of relapses does not always mean that the disease has completely stopped progressing. Sometimes neurological function continues to deteriorate slowly. In medical literature, this condition is known as progression independent of relapse activity, or PIRA.
Detecting it at an early stage is not easy. Changes may occur gradually, and the results of individual neurological examinations do not always make it possible to immediately identify the overall trend.
For this reason, doctors and researchers are looking for objective indicators that could complement neurological examinations and magnetic resonance imaging data.
What Is GFAP?
GFAP is a protein associated with astrocytes. These are cells of the nervous system that support neuronal function and are involved in the brain’s response to injury.
With certain changes in the central nervous system, the concentration of GFAP in the blood may increase. Researchers suggest that regular measurement of this biomarker could provide additional information about processes associated with the gradual progression of multiple sclerosis.
It is important to understand that GFAP is not a test that can be used on its own to make a diagnosis or decide whether treatment should be changed. It is a promising biomarker whose clinical significance is still being studied.
What the Study Found
A research group led by Professor Jens Kuhle analyzed 18,629 blood samples obtained from 2,329 patients with multiple sclerosis. The study used data from two large observational cohorts in Switzerland and the United States.
The results showed that elevated GFAP levels were associated with a higher risk of subsequent deterioration in neurological function occurring independently of relapses.
The researchers also assessed changes in the biomarker after treatment was initiated. A decrease in GFAP during the first two years of treatment was associated with a lower risk of subsequent disease progression.
This does not mean that a single blood test can already accurately predict the future course of the disease for an individual patient. However, monitoring GFAP levels over time may prove more useful than a single measurement.
GFAP and NfL: Two Different Biomarkers
Another biomarker — neurofilament light chain, or NfL — is already used in the diagnosis and monitoring of multiple sclerosis. Its concentration in the blood helps assess nerve fiber damage and primarily reflects inflammatory disease activity.
According to the results of the new study, GFAP may reflect another aspect of the disease — gradual deterioration without obvious relapses.
In the future, the combined assessment of GFAP and NfL could provide doctors with a more complete picture:
- NfL may indicate nerve fiber damage and inflammatory activity;
- GFAP may provide additional information about the risk of hidden progression;
- repeated blood tests may help assess changes during treatment.
However, blood tests do not replace consultation with a neurologist, MRI scans, or clinical assessment of the patient’s condition.
What This Could Change for Patients
If further studies confirm the practical value of GFAP, doctors may be able to identify patients at increased risk of multiple sclerosis progression at an earlier stage.
This could help:
- assess the individual course of the disease more accurately;
- monitor patients in high-risk groups more closely;
- evaluate the patient’s response to prescribed therapy;
- discuss possible treatment adjustments in a timely manner;
- conduct research on new medications more effectively.
In addition, GFAP may be useful when selecting participants for clinical trials focused on progressive forms of multiple sclerosis.
When Will the New Test Become Part of Clinical Practice?
It is still too early to consider GFAP a standard test that every patient with multiple sclerosis should undergo regularly. The study demonstrated a statistical association between biomarker levels and the risk of progression, but widespread clinical use will require standardized reference ranges, an optimal testing frequency, and clear guidelines for interpreting the results.
It is particularly important to take into account the patient’s age, the form of the disease, ongoing treatment, and other factors that may influence blood biomarker levels.
Therefore, the need for such testing should be discussed with a multiple sclerosis specialist. Interpreting GFAP results without medical guidance may lead to incorrect conclusions and unnecessary anxiety.
Multiple Sclerosis: The Importance of Personalized Monitoring
Multiple sclerosis can progress differently even among patients of the same age and with the same duration of the disease. For this reason, there is no universal approach to monitoring and treatment.
The combination of neurological examinations, MRI, laboratory biomarkers, and assessment of the patient’s well-being is gradually moving medicine toward more personalized disease monitoring.
Research into GFAP represents another important step in this direction. The new biomarker does not replace existing diagnostic methods, but in the future it may help doctors detect changes that currently remain unnoticed during standard monitoring.
If you need a consultation regarding the diagnosis or treatment of multiple sclerosis in Switzerland, we can help you select a specialized clinic and arrange an appointment with the appropriate medical specialists.