Repetitive TMS in treatment of resistant diabetic neuropathic pain

BackgroundDiabetes mellitus is a clinical syndrome characterized by hyperglycemia caused by respective or absolute deficiency of insulin. Painful neuropathy in diabetic population is popular, impacting numerous chronic diabetic patients. Although antidepressants, anticonvulsants, and opioid agonists are useful in alleviating painful neuropathy, they produce a diversity of side effects and are occasionally ineffective. Hence, there is presently a need to pursue safe, non-invasive, and effective therapeutic opportunities. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive mechanism used in releasing neuropathic pain. TMS pulseswhen applied repetitivelycan modulate cortical plasticity, consequently causing excitability or inhibition according to the rate of stimulation.ObjectivesThe aim of this study is to evaluate the efficacy of repetitive transcranial magnetic stimulation (rTMS) in improving resistant chronic diabetic neuropathic pain.Subjects and methodsTwenty patients were recruited and divided equally into two groups: insulin-dependent (group A) and non-insulin-dependent (group B). A high-frequency (10Hz) rTMS stimulation protocol was applied to both groups for five consecutive days over lower limbs motor cortex. VAS score and nerve conduction studies were compared before and after rTMS sessions.ResultsHighly significant improvements in VAS and nerve conduction studies (p>0.01) were detected for both patient cohorts following the administration of the rTMS protocol.ConclusionAccording to our study, rTMS significantly reduced painful diabetic neuropathy. rTMS may produce its analgesic effects, inducing motor cortex plasticity and activating descending inhibitory pain control systems.