Using quantitative EEG, a non-invasive computerized measurement of brain wave patterns, the researchers discovered that specific changes in brain-wave activity precede clinical changes brought on by medication. The new findings, published in the July edition of the peer-reviewed journal Neuropsychopharmacology, could lead to treatment programs that help depression patients feel better faster by cutting evaluation periods from weeks to days. The findings also could aid in the development of new medications.
"Up to 40 percent of depressed patients do not respond to the first medication they try. Since it takes several weeks for an effective treatment to produce clear improvement, doctors often wait six to 12 weeks to decide that a particular medication just isn't right for that patient and move on to another treatment," said Dr. Ian A. Cook, a researcher at the institute's Quantitative EEG Laboratory and lead author of the study.
"By comparing EEG measurements before treatment with those soon after treatment begins, doctors may be able to evaluate the usefulness of an antidepressant within days rather than having to wait weeks to months," Cook said. "This technique also could slash the time and costs needed to develop and research new antidepressants."
The study examined 51 adult patients diagnosed with acute depression. Each participated in one of two, double-blind, randomized treatment trials. One group received the antidepressant fluoxetine or placebo. The other received the antidepressant venlafaxine or placebo. (A placebo is an inactive substance, such as a sugar pill.) Each subject received a quantitative EEG prior to treatment, 48 hours after treatment and one week after treatment.