February 21, 2024

For the first time, scientists have identified a new subtype of depression that involves more pronounced cognitive dissonance that current treatments have failed to alleviate.

Researchers led by a team at the Stanford University School of Medicine used surveys, tests and brain imaging to document cognitive impairment, characterized by behaviors such as difficulty planning ahead, lack of self-control, difficulty concentrating and other executive function problems.

Although executive function difficulties have been known to be a factor Scientists believe it has been known for some time for major depressive disorder, which for as many as 27 percent of patients, is a major problem that most current medications fail to target. Although this group is a minority, approximately 5 million people in the United States still suffer from depression.

“Depression manifests itself in different ways in different people, but finding commonalities — such as similar brain function profiles — could help medical professionals effectively treat participants with individualized care,” said senior author, Psychiatry and behavioral science professor Leanne Williams.

Often, doctors prescribe selective serotonin reuptake inhibitors (SSRIs), but they are less effective at helping cognitive dysfunction.

In the study, 1,008 medication-naive adults with major depression took one of three common antidepressants — escitalopram (also known as Lexapro) and sertraline (Zoloft), Acts on serotonin, and Venlafaxine-XR (Effexor), acts on serotonin and norepinephrine. At the end of the eight weeks, 712 participants had completed the study.

Before and after, participants took a clinician-administered self-assessment survey to assess various symptom levels, as well as behaviors such as sleep or dietary changes and social and work-life impacts. They also underwent cognitive tests, measuring brain functions such as working memory, decision-making speed and sustained attention.

In addition, the brains of 96 of the participants underwent functional magnetic resonance imaging (fMRI) scans, during which the scientists observed brain activity compared with participants without depression using a response test.

After eight weeks, the team found that 27 percent of the participants had more severe cognitive impairment and reduced activity in specific frontal brain regions, namely the dorsolateral prefrontal cortex and dorsolateral anterior cingulate area. SSRIs also showed the least improvement.

“This study is critical because psychiatrists have few tools to measure depression to help make treatment decisions,” said the study’s lead author, Dr. Laura Harker, an assistant professor of psychiatry and behavioral sciences. are observational and self-report measures. Imaging while performing cognitive tasks is fairly novel in depression treatment research.”

From this, the researchers hope to develop tests to detect this dysregulation and alter treatment to better suit this subtype of major depressive disorder.

“One of the biggest challenges is finding a new way to address the current trial-and-error process so that more people can recover more quickly,” Williams said. “Introducing objective cognitive measures such as imaging will ensure that we don’t Every patient uses the same treatment.”

Williams and Harker hope to conduct further research in people with this cognitive biotype, using different treatments such as transcranial magnetic stimulation (TMS) and cognitive behavioral therapy (CBT), as well as other drugs such as guanidine Sim, it’s more commonly associated with attention deficit hyperactivity disorder (ADHD).

Not surprisingly, these same brain regions identified in the study are also the ones affected by ADHD and the executive function associated with it.

“I’ve often witnessed the pain, loss of hope, and increased suicide rates that people experience as they go through our trial and error process,” Harker said. medications to start, although depression is quite different. I think this research can help change that.”

The study was published in the journal JAMA Network Open.

source: Stanford University School of Medicine