UCLA researchers say changes in brain function in first 48 hours are key
While antidepressant medications have proven to be beneficial in helping people overcome major depression, it has long been known that a small subset of individuals taking these drugs can actually experience a worsening of mood, and even thoughts of suicide. No clinical test currently exists to make this determination, and only time - usually weeks - can tell before a psychiatrist knows whether a patient is getting better or worse.
Now, UCLA researchers have developed a non-invasive biomarker, or indicator, that may serve as a type of early warning system.
Reporting in the April edition of the peer-reviewed journal Acta Psychiatrica Scandinavica, Aimee Hunter, an assistant research psychologist in the UCLA Department of Psychiatry, and colleagues report that by using quantitative electroencephalographic (QEEG), a non-invasive measurement of electrical activity in the brain, they were able to observe a sharp reduction of activity in a specific brain region in individuals who proved susceptible to thoughts of suicide - within 48 hours of the start of treatment.
Prior research, Hunter said, has shown that between 8 and 14 percent of depressed patients develop thoughts of suicide while taking the most common forms of depression drugs, known as selective serotonin reuptake inhibitors (SSRI). Although reports have suggested that SSRIs are to blame, no firm link between these drugs and thoughts of suicide has been established.
This study suggests, for the first time, a link between worsening suicidality and specific changes in brain function while on these medications.
The researchers treated 72 people suffering from major depressive disorder (MDD) with one of two SSRIs, fluoxetine or venlafaxine, or with a placebo. All were evaluated by a clinician using the Hamilton Depression Rating Scale, a standard instrument that assesses the severity of a wide range of depression symptoms. Of the 37 participants on medication, five (13.5 percent) had worsening thoughts of suicide.