A new neurological test promises to fast-track the antidepressant treatment experience for millions of affected subjects.

Choosing the most effective antidepressant medications is often a painful case of trial-and-error. Because most meds take weeks to begin relieving symptoms and many subjects must try several brands before finding one that works, the selection process can be extremely long and frustrating and may actually complicate the conditions of those suffering through major depression.

This unfortunate pattern may soon change. The Aspect Medical Systems company claims to have developed a bio-marker test called Antidepressant Treatment Response (ATR) that can determine, within a week, which meds will be most effective for specific subjects. And a company-sponsored research report appears to support their claims. The study, known as the Biomarkers for Rapid Identification of Treatment Effectiveness trial in Major Depression (BRITE-MD), examined the results of the test, which is based on the familiar EEG brain scanning technology. EEG is a technique that's long been used to identify subjects with neurological disorders. It can detect even the most miniscule changes in brainwave activity.

The test works from the demonstrable fact that the antidepressants cause changes in brain activity long before they actually start working. Even though subjects may wait weeks or months to experience symptomatic improvement, their brains begin visibly responding to these medications within a week. By scanning the brain's inital response to these drugs after a short trial period, researchers can quickly label them effective or ineffective. Conclusions are largely based on the degree to which each depressed subject's brain activity has shifted from the baseline patterns established at the study's onset. If doctors notice no positive changes after a week or more, they can label the meds ineffective and move on to alternatives. 

In the official study, researchers at nine locations across the country examined 375 subjects who began taking the antidepressant escitalopram (Lexapro) at the study's onset. They noted the results of one-week ATR tests and compared the pool of subjects who'd shown improvements after one week to those who noted fewer symptoms after the seven-week period ended. Final analysis found that the ATR test predicted seven-week results at a significant 74% accuracy rate. The data also noted that subjects whose ATR tests predicted an unsuccessful response to Lexapro had better seven-week outcomes when researchers replaced the drug with bupropion (Welbutrin, Zyban). The test is imperfect, of course, but if these results hold true on a larger scale it could definitely improve the overall efficiency of medication-based depression treatments. 

Antidepressant medications almost never serve as miraculous cure-alls, and many of the most deeply affected subjects will continue to struggle through the stages of their treatments. Tests like the ATR, however, may be able to eliminate unneccessary trial periods and significantly reduce the amount of time between a subject's first doctor's visit and his or her eventual recovery.