| Paper authors: | Kfir Feffer, Hyewon Helen Lee, Farrokh Mansouri, Peter Giacobbe, Fidel Vila-Rodriguez, Sidney Kennedy, Zafiris Daskalakis, Daniel Blumberger, Jonathan Downar |
| Year of paper publication: | 2018 |
| Post authors: | Alice Erchov, Lisa Ridgway Fidel Vila-Rodriguez |
| Download the research article: | Feffer et al. (2018) Early symptom improvement at 10 sessions as a predictor of rTMS treatment outcome in major depression |
Introduction
Not improving after investing time, money, and energy into a treatment for depression is, understandably, difficult. This may be especially true for people who resort to second-line treatments, such as repetitive transcranial magnetic stimulation (rTMS) after typical antidepressants already failed to help them. Thus, being able to predict who will respond to what treatment would help clinicians and patients personalize treatment approaches. The hope is to reduce these frustrations and, possibly, more effectively treat depression.
Previous attempts to look at what might predict a depressed individual’s treatment response to rTMS have been limited because they are either unreliable when looking at a single individual (as opposed to a group) or inaccessible (e.g., expensive techniques to image the brain). Looking at early symptom improvement might be promising: it is information that is relatively easy to obtain and specific to an individual. Thus, this study looked at whether early depression symptom improvement would be able to reliably predict whether someone will respond to rTMS.
Methods
This study looked at a total of 101 patients with depression that were treatment-resistant (having tried at least one medication in the past, without improvement). Everyone received either rTMS or its accelerated version, iTBS, every weekday for 4 weeks (20 treatments total). Participants self-reported (told researchers) about how severe their depression was after every 5 treatments.
Results
- Researchers could predict that patients who showed less than 20% improvement in their depression symptoms after 2 weeks of treatment were unlikely to see more than 35-50% improvement in their depressive symptoms by the end of the full course of treatment
- This was predictable with up to 92% accuracy
- It was possible to predict future response from as early as 1 week into treatment
- Patients who showed less than 10% improvement in their depression symptoms by the end of the first week were unlikely to see more than 35-50% improvement in their depressive symptoms by the end of the full course of treatment
- This was slightly less accurate than the 2 week measurement
Conclusion
This study showed that early symptom non-improvement to rTMS could reliably predict future treatment non-response. This doesn’t mean giving up on the treatment entirely. Instead, it may mean exploring alternatives like adjusting the treatment schedule, target (location of stimulation), or intensity. Knowing who and what treatment is best for an individual allows clinicians to help patients more effectively with their depression.