New Type of Depression Identified, May Boost Treatment Outcomes

A recent study conducted by scientists at Stanford Medicine has shed light on a new type of depression known as the cognitive biotype. This specific subtype, accounting for 27% of depressed patients, is characterized by difficulties in planning ahead, displaying self-control, sustaining focus, and suppressing inappropriate behavior.

But why is this finding important?

You see, a drug can only be effective when it targets the illness for which it is designed.

Popular antidepressants such as selective serotonin reuptake inhibitors (SSRIs) typically target serotonin. These drugs are not very effective in treating cognitive dysfunction, which characterizes this newly identified type of depression.

The result is that, although you'd be using antidepressants, your depression symptoms will likely not go away. This leads to poor treatment outcomes, simply because the same drug is used for different conditions. Think treatment-resistant depression.

If there's a type of depression associated with cognition rather than serotonin, then treatment targeting cognitive dysfunctions rather than serotonin will probably be more effective. This is the presumption held by the researchers.

The study, published in JAMA Network Open, forms part of a broader effort by neuroscientists to identify and develop treatments that target specific depression biotypes. According to Leanne Williams, Ph.D., the study's senior author, adding objective cognitive measures like imaging in treatment processes will create a more personalized approach, moving away from the current trial-and-error method.

The study involved 1,008 adults with major depressive disorder. They were all given commonly prescribed antidepressants.

Cognitive tests and imaging revealed that patients with the cognitive biotype experienced symptoms of cognitive slowing, insomnia, impaired cognitive function, and reduced activity in specific frontal brain regions. These brain regions are necessary for cognitive control, including limiting unwanted thoughts and responses, improving goal selection, and more.

After the treatment period, patients with the cognitive biotype had lower recovery compared to other patients without it. Among the antidepressants administered, sertraline showed the most significant difference in remission rates between the two groups.

Individualized depression treatment can lead to better treatment outcomes

The researchers propose that behavior measurement and imaging could help in diagnosing different depression biotypes, leading to more targeted and effective treatments. In that case, patients showing specific biotypes may undergo imaging to confirm the type of depression they have before receiving treatment.

Additionally, ongoing studies are exploring the potential of guanfacine for individuals with the cognitive subtype. Guanfacine is a medication that specifically targets the dorsolateral prefrontal cortex.

The ultimate goal is to individualize depression treatment by considering the unique profiles of brain function that patients exhibit. By tailoring treatments to specific depression biotypes, the suffering experienced by individuals undergoing the current trial-and-error process can finally be alleviated.