by Jenny Picciotto
The National Institute of Health reported recently on a new model for predicting whether antidepressant therapy will lead to remission. Researchers studied how measuring early life stress and evaluating how the brain processes emotions can predict the success of antidepressants. Results of the study were published by the Proceedings of the National Academy of Sciences this October.
Depression is a common disorder that can have severe symptoms that interfere with many aspects of daily life. It frequently co-occurs with severe illness or chronic pain, but is also prevalent among the general population.
In 2015, 6.7 percent of the adult population of the United States was diagnosed with clinical depression, defined as:
“A period of two weeks or longer during which there is either depressed mood or loss of interest or pleasure, and at least four other symptoms that reflect a change in functioning, such as problems with sleep, eating, energy, concentration, and self-image.”
Treatment may include antidepressant medication, with or without psychotherapy.
Over the last 50 years, the stigma that once accompanied seeking treatment for a mental disorder has largely faded, but many people still don’t get help. While some may not recognize that they are depressed, or don’t realize that help is available; some people internalize depression as a weakness, thinking they should be able to control their mood. This research points to the effect of changes in the structure and function of the brain because of stress as a causative factor in developing depression.
Previous research has linked early life stress (ELS) and changes in the amygdala as factors that individually increase the risk of developing depression as an adult. The amygdala is part of the brain that regulates emotion, fear, and response to stress. Increased levels of stress hormones can change the circuitry of this emotional processing center.
“Stress, especially ELS, produces the cascade of neurobiological changes that disrupt emotion regulation and generate depression in adulthood.”
These changes in the brain reduce the ability to control emotion, which can lead to the “increased negative bias and overly negative evaluation of the self that are fundamental features of human depression.” This is the first study to investigate how these factors can predict the effectiveness of treatment with antidepressants.
70 patients were surveyed to determine how much early life stress (ELS) they were exposed to. Using brain imaging technology, researchers measured emotional response to images representing a threat (angry faces) or a reward (happy faces). By evaluating various combinations of these factors, researchers were able to predict which patients would benefit from antidepressant therapy with 80% accuracy.
Patients who experienced lower levels of ELS, and had lower levels of reactivity to positive or negatively charged images, were more likely to respond. Patients who experienced high levels of ELS, and were more reactive to threat, were less likely to benefit from antidepressant therapy. These individuals may benefit from psychotherapy in addition to, or prior to, treatment with antidepressants.
While the authors recommend further research to factor in the effectiveness of newer medications and psychotherapy, this study has clinical application which could lead to more effective treatment.
Lead researcher Dr. Leanne Williams says “We were able to show how we can use an understanding of the whole person – their experiences and their brain function and the interaction between the two – to help tailor treatment choices.”
Jenny Picciotto is a writer who has CRPS and facilitates a CRPS support group. She is currently working on a larger project that will include this article, but has given us permission to publish this article in the meantime. She is also a massage therapist and yoga instructor, and enjoys thinking deeply about simple things.