A novel intermittent dosing burst paradigm in spinal cord stimulation (SCS) has effectively relieved pain in patients with chronic intractable pain. Authors Timothy Deer, president and CEO of The Spine and Nerve Centre of the Virginias, Charleston, USA, and colleagues report that the current findings present “intriguing implications” for the optimal “dose” of electricity in SCS, and may offer numerous advantages such as optimising the therapeutic window, extending battery life, reducing recharge burden, and may “potentially mitigating therapy habituation and tolerance”.
On the rationale behind intermittent dosing, the authors point to the fact that the cycling of stimulation, which consists of altering the amount of time stimulation is active (ON) and inactive (OFF), is a feature that has been available to SCS clinicians for years. Yet, the tool has not been systematically studied with the goal of reducing the total amount of stimulation delivered to the spinal cord in a patient tailored fashion.
Deer and colleagues acknowledge that as the optimal clinical settings for intermittent dosing using the burst paradigm are unknown, the main objective of the study was to evaluate the feasibility of the stimulation, in patients with chronic intractable pain who have never previously received SCS therapy.
The prospective, multicentre, feasibility trial, recently published in Neuromodulation, was conducted to evaluate the clinical efficacy of certain intermittent dosing stimulation-off times: 90, 120, 150 and 360 seconds, with burst waveform parameters. According to the authors, following a successful trial with this stimulation, defined as ≥50% pain relief, subjects were titrated with OFF times beginning with 360 seconds. Subsequently, pain, quality of life, disability, and pain catastrophizing were evaluated at one, three and six months after permanent implant.
In total, 50 subjects completed an SCS trial with intermittent dosing, with 38 (76%) receiving ≥50% pain relief. Deer et al reported that pain scores were significantly reduced from baseline at all time points (p<0.001). “Improvements in quality of life, disability, and pain catastrophizing were aligned with pain relief outcomes,” the authors write, adding that 45.8% of the subjects that completed the six-month follow-up visit used an OFF period of 160 seconds.
“Our results demonstrate that intermittent dosing burst SCS is safe and efficacious in subjects with chronic back and/or leg pain,” Deer and colleagues highlight.
Discussing the clinical implications, they write: “These results suggest that intermittent stimulation can be titrated to provide optimal pain relief while delivering the lowest possible dose of electricity to the spinal cord. This may help extent device battery life, and potentially reduce or delay therapy habituation.”