More than half of patients with major depressive disorder (MDD) experience a relapse of symptoms less than two years after recovery. This recurrence may be associated from a patient's initial MDD experience that causes morphologic changes in brain regions responsible for regulating emotions and cognitive control, according to a March 28 study in the Journal of the American Medical Association (JAMA).
"Structural neuroimaging techniques may provide insights into the underlying neural mechanisms of relapse," wrote lead author Dario Zaremba, MSc, from the department of psychiatry and psychotherapy at the University Hospital Münster in Münster, Germany. "In the long term, understanding the neuronal correlates could support prognosis of relapse and thus improve maintenance treatment in patients with recurrent MDD."
Structural MRI technology helped identify these changes in patients with acute MDD at baseline compared to health controls who were recruited from the psychiatry department at the University of Münster, from March 21, 2010, to November 14, 2014. The final cohort consisted of 60 patients experiencing depression (23 patients without relapse; 12 women and 10 men, mean age of 32), severe depression (37 patients with relapse; 19 women and 18 men, mean age of 37) and 54 healthy controls (24 women and 30 men, average age of 37), according to study methods.
Participants were then reassessed and subdivided into groups of patients with and without relapse. Assessments two years after baseline included whole-brain gray matter volume and cortical thickness of the anterior cingulate cortex, orbitofrontal cortex, middle frontal gyrus and insula.
Zaremba and colleagues concluded that MDD patients who experienced a relapse showed different patterns of cortical gray matter changes compared to healthy controls and MDD patients who did not experience a relapse.
"Our observed effect of relapse on insular morphologic features is supported by previous studies showing an association of insular volume change over time and patients’ course of illness, such as duration of illness and number of depressive episodes," the researchers wrote.
Additional study results included the following:
- Patients who experienced at least one relapse between scans showed a decline of insular volume and dorsolateral prefrontal cortex volume and thickness from baseline to follow-up.
- In patients without relapse, gray matter volume in these regions was stable, whereas cortical thickness increased in the left medial orbitofrontal cortex, left rostral anterior cingulate cortex and right insula.
- Volume changes from baseline to follow-up were not associated with psychiatric medication or with severity of depression.
In an accompanying JAMA editorial, Mary Phillips, MD, professor of psychiatry at the University of Pittsburgh, explained that the study findings highlight underlying neural mechanisms of relapse and MDD and suggest that focusing on neural regions in the early stages after an initial MDD episode has the potential to "provide early markers of likely future illness course" and enhanced treatment options.
"In a climate where the role of neuroimaging techniques in psychiatry remains unrealized, this study highlights the potential real-world utility of these techniques as clinical tools to provide information that can considerably influence long-term treatment choices to improve clinical outcomes for many people with MDD," Phillips wrote.
A recent graduate from Dominican University (IL) with a bachelor’s in journalism, Melissa joined TriMed’s Chicago team in 2017 covering all aspects of health imaging. She’s a fan of singing and playing guitar, elephants, a good cup of tea, and her golden retriever Cooper.