Thursday, September 24, 2009

Quantitative EEG Biomarker Depression

One of the problems that we have had in the medication treatment of depression is that we don't have a way of predicting who will respond well to any given antidepressant. Because it takes up to several weeks for any antidepressant to be effective it often takes a long time to find the right medication that the patient will respond to and which has tolerable side effects. This is very frustrating both for the patient and the provider and results in long periods of suffering. What we have needed is some way, a biomarker which can predict accurately very early on whether the medication will effective or not. Aspect Medical Systems claim they have found one such biomarker.

There are two studies being published in the September issue of Psychiatric Research from what is being called the Biomarkers for Rapid Identification of Treatment Effectiveness study. The first report is of 375 patients aged 18-75 who suffered from major depression. Using the non invasive technique of quantitative electroencephalography the researchers report they determined after one week of treatment by measurements in the prefontal cortex who would respond to the antidepressant escitalopram (Lexapro). They reported that they could accurately predict what was going to happen at seven weeks with 74% accuracy.

The second study reported by the same researchers on the same group of patients showed that for those who did not show the biomarker on quantitative EEG that those switching to the antidepressant buproprion (Wellbutrin) were 1.9 times likely to respond to the new drug. It sounds very promising ..... but......

The research was highly funded by Aspect Medical Systems which makes the electrodes used in the study. Although the researchers are supposed to be independent the lead investigator disclosed that he has provided scientific consultation or served on the advisory board of Aspect Medical Systems and that he is also a minor stockholder as well.

The need for a biomarker is so great that this testing may be used on many patients before there has been any time to assess if anyone else can replicate their results. The quantitative EEG device is already in use for other conditions so already has FDA approval. The technique carries almost no risk greater than the hassle of getting the electrode goop out of your hair. So I am not concerned about any harm to patients but rather that many providers may be buying these devices, and using them prematurely before the evidence is in (and making a lot of money for the procedure charges).

Thought for the day

Sometimes only time will tell.

No comments:

Post a Comment

Thank You For Your Comment!

CARF - Commission on Accreditation of Rehabilitation FacilitiesNATSAP | National Association of Therapeutic Schools and ProgramsNBCCNAADAC