Association between increased theta cordance and early response to ECT in late‐life depression

Abstract

Objectives-More than half of patients with major depression who do not respond to initial antidepressants become treatment resistant (TRD), and while electroconvulsive therapy (ECT) is effective, it involves anesthesia and other medical risks that are of concern in geriatric patients. Past studies have suggested that theta cordance (TC), a correlate of cerebral metabolism measured by electroencephalography, could guide treatment decisions related to patient selection and engagement of the therapeutic target. Methods/Design-Eight patients with late-life treatment resistant depression (LL-TRD) underwent magnetoencephalography (MEG) at baseline and following seven sessions of ECT. We tested whether the mean and regional frontal cortex TC were able to differentiate early responders from nonresponders. Results-Five patients whose depression severity decreased by >30% after seven sessions were considered early responders. We found no baseline differences in mean frontal TC between early responders compared with nonresponders, but early responders exhibited a significant increase in TC following ECT. Further, we found that compared with nonresponders, early responders exhibited a greater change in TC specifically within the right prefrontal cortex. Conclusions-These results support the hypothesis that increases in frontal TC are associated with antidepressant response. We expand on previous findings by showing that this change is specific to the right prefrontal cortex. Validation of this neural marker could contribute to

Using EEG to Predict Clinical Response to Electroconvulsive Therapy in Patients With Major Depression: A Comprehensive Review

“…Stubbeman and colleagues found an association between clinical response and central cordance ( 26 ). Most recently, in a magnetoencephalography study in late-life depression, no difference was found at baseline between early responders and non-responders in mean frontal theta cordance ( 43 ). These results are contradictory.…”

Closed-Loop Brain Stimulation

“…The prefrontal theta rhythm has been implicated in neurocognitive processes, such as working memory ( 65 , 66 ) but also in mood control ( 67 ). In particular, the increase of prefrontal activity in the theta band after electroconvulsive therapy ( 68 ) and the increase in frontoparietal connectivity in the theta band after magnetic seizure therapy ( 69 ) have been found to be predictive of treatment response in patients with MDD.…”

Prevalence of Comorbid Dementia in Late-life Depression and Bipolar Disorder: A Retrospective Inpatient Study

“…We investigated the prevalence of dementia at This is because HAMD is well known as the rating scale for the late life depression or depression in dementia [18,19], and recommended as the rating…”