Five-Year Follow-Up of Bilateral Epidural Prefrontal Cortical Stimulation for Treatment-Resistant Depression

- Five year follow-up on epidural prefrontal cortical stimulation treatment for depression.
- Long-term safety and efficacy outcomes were assessed.
- All 5 patients tolerated therapy at 5 years, 3/5 continued to be in remission.
- Five adverse events resulting in suicidal ideation and/or hospitalization occurred.

BackgroundEpidural prefrontal cortical stimulation (EpCS) represents a novel therapeutic approach with many unique benefits that can be used for treatment-resistant depression (TRD).ObjectiveTo examine the long-term safety and efficacy of EpCS of the frontopolar cortex (FPC) and dorsolateral prefrontal cortex (DLPFC) for treatment of TRD.MethodsAdults (N = 5) who were 21-80 years old with severe TRD [failure to respond to adequate courses of at least 4 antidepressant medications, psychotherapy and ≥20 on the Hamilton Rating Scale for Depression (HRSD24)] were recruited. Participants were implanted with bilateral EpCS over the FPC and DLPFC and received constant, chronic stimulation throughout the five years with Medtronic IPGs. They were followed for 5 years (2/1/2008-10/14/2013). Efficacy of EpCS was assessed with the HRSD24 in an open-label design as the primary outcome measure at five years.ResultsAll 5 patients continued to tolerate the therapy. The mean improvements from pre-implant baseline on the HRSD24 were [7 months] 54.9% (±37.7), [1 year] 41.2% (±36.6), [2 years] 53.8% (±21.7), and [5 years] 45% (±47). Three of 5 (60%) subjects continued to be in remission at 5 years. There were 5 serious adverse events: 1 electrode 'paddle' infection and 4 device malfunctions, all resulting in suicidal ideation and/or hospitalization.ConclusionThese results suggest that chronic bilateral EpCS over the FPC and DLPFC is a promising and potentially durable new technology for treating TRD, both acutely and over 5 years.