The following is a summary of “Prediction of the response to repetitive transcranial magnetic stimulation of the motor cortex in peripheral neuropathic pain and validation of a new algorithm,” published in the June 2024 issue of Pain by Attal, et al.

While Motor cortex repetitive transcranial magnetic stimulation (M1-rTMS) shows promise as a pain reliever for neuropathic conditions, individual responses vary significantly, with no way to tell who will benefit beforehand.

Researchers conducted a retrospective study to identify factors that could predict an individual’s response to M1-rTMS for chronic pain.

They conducted a secondary analysis using data from a recent double-blind, placebo-controlled trial, showing the effectiveness of high-frequency M1-rTMS compared to placebo-rTMS and rTMS of the dorsolateral prefrontal cortex in 149 patients with peripheral neuropathic pain.

The results showed that baseline variables were impartially entered into the model and categorized into sociodemographic, pain, and psychological factors. Effective responders to rTMS achieved a 50% reduction in average pain intensity (rated on a 0-10 scale) at 25 weeks. Ridge regression, feature selection, and Monte Carlo cross-validation techniques were employed to develop and validate a predictive model specific to M1-rTMS response at 25 weeks. The algorithm incorporated 3 variables, 2 psychological (depressive symptoms, Pain Catastrophizing Scale magnification) and 1 related to pain distribution (distal lower extremity pain). It demonstrated 85% sensitivity (P=0.005) and 84% specificity (P<0.0001) in predicting a favorable response to M1-rTMS at 25 weeks and did not predict response to placebo or dorsolateral prefrontal cortex-rTMS.

Investigators concluded that the algorithm has the potential to personalize M1-rTMS treatment for chronic neuropathic pain in clinical practice and future trials.

Source: journals.lww.com/pain/abstract/9900/prediction_of_the_response_to_repetitive.625.aspx