Distinct Predictors of Clinical Response after Repetitive Transcranial Magnetic Stimulation between Bipolar and Unipolar Disorders.

Background: Repetitive transcranial magnetic stimulation (rTMS) has been shown to be therapeutically effective for patients suffering from drug-resistant depression. The distinction between bipolar and unipolar disorders would be of great interests to better adapt their respective treatments. Methods: We aimed to identify the factors predicting clinical improvement at one month (M1) after the start of rTMS treatment for each diagnosis, which was preceded by a comparison of the patients' clinical conditions. We used the data collected and the method employed in a previous publication on 291 patients. Results: Although the bipolar group had fewer responders, these patients seemed to better maintain their post-rTMS improvement on anxiety and perception of the severity of their illness than those in the unipolar group. For the bipolar group, young age coupled with low number of medications and high fatigue was shown to be the best combination for predicting improvement at M1. The duration of current depressive episode, which was previously demonstrated for whole group, combined with being attached was shown to favor clinical improvement among the patients in unipolar group. Conclusion: We were able to define a combination of specific factors related to each diagnosis for predicting the patients' clinical response. This could be extremely useful to predict the efficacy of rTMS during routine clinical practice in neuromodulation services.

Predictors of clinical response after rTMS treatment of patients suffering from drug-resistant depression.

Repeated transcranial magnetic stimulation (rTMS) is a therapeutic brain-stimulation technique that is particularly used for drug-resistant depressive disorders. European recommendations mention the effectiveness of 30 to 64%. The failure rate of treatment is high and clinical improvement is visible only after a certain period of time. It would thus be useful to have indicators that could anticipate the success of treatment and more effectively guide therapeutic choices. We aimed to find predictive indicators of clinical improvement at 1 month after the start of rTMS treatment among the data collected during the care of patients with drug-resistant depression included in the Neuromodulation Unit of the Esquirol Hospital in Limoges since 2007. In total, 290 patients with a pharmaco-resistant depressive episode, according to the Hamilton Depression Rating Scale (HDRS) (score ≥8), before treatment who underwent a complete course of rTMS treatment and did not object to the use of their collected data were included. The clinical response in routine practice, corresponding to a decrease in the HDRS score of at least 50% from inclusion, was determined and complemented by interquartile analysis. A combination of factors predictive of clinical response during care, such as a short duration of the current depressive episode associated with a higher HDRS agitation item value (or a lower perceived sleepiness value) and a higher number of previous rTMS treatments, were identified as being useful in predicting the efficacy of rTMS treatment in routine clinical practice, thus facilitating the therapeutic choice for patients with drug-resistant depression.