EEG readings may act as biomarker of CJD progression

Electroencephalogram (EEG) readings may act as a biomarker of disease progression in Creutzfeldt-Jakob disease (CJD), according to research published in The Journal of Neurology, Neurosurgery, and Psychiatry.

The use of recording brain waves via an EEG has long been used in the diagnosis of prion diseases, particularly CJD. However, researchers have now found more information can be extracted from the recordings, by looking at the background waveforms that are generated by the brain, called quantitative EEG.

Senior author on the paper Professor Simon Mead said: “We noticed that brain waveforms change as CJD progresses – both in their frequency and strength. We used statistical techniques to extract information about these waveforms; the changes we observed were strong and will help us monitor brain function through the course of the disease.”

The electrical waves recorded by EEG emerge from neuronal activity on the surface of the brain – the waves are essentially the firing of different nerve cells. Each EEG electrode records from the synchronous firing of tens of thousands of neurons under the skin and beneath the skull on the surface of the brain.

To find out how the brain waveforms correlated with the severity of CJD, the team divided the different waveforms into frequency bands: the alpha band tended to decrease, whereas the theta band tended to increase as the disease progressed. As a result, the team found the ratio between the two tended to change very significantly. These big effects were widespread across the brain and strongly correlated with the severity of the disease.

The team hope the BRC supported study will help accelerate the development of therapeutics. Professor Mead said: “We hope to develop the tools that will allow us to monitor disease progression, so when we use an experimental therapeutic we will have a range of tests that will tell us whether the drug is working. We hope to introduce experimental treatments soon for CJD, we may use a compassionate treatment as part of NHS care; and tools like quantitative EEG to monitor patients on treatment.”

Visit The Journal of Neurology, Neurosurgery, and Psychiatry to read Quantitative EEG parameters correlate with the progression of human prion diseases in full.