Comparative efficacy and safety of high-frequency, low-frequency, and burst spinal cord stimulation for painful...

Painful diabetic neuropathy (PDN) is a common complication of diabetes that substantially impairs quality of life and remains challenging to manage. Spinal cord stimulation (SCS), including high-frequency (HF-SCS), low-frequency (LF-SCS), and burstDR (burstDR-SCS) modalities delivered with the De Ridder algorithm, has emerged as a therapeutic option for patients with inadequate response to conventional medical management (CMM). However, the comparative efficacy and safety profiles of these specific SCS modalities remain unclear. A systematic search identified 1,243 records, from which seven studies involving 698 patients met the inclusion criteria and were analyzed using a random-effects Bayesian network meta-analysis framework with minimally informative priors. Primary outcomes included the proportion of patients achieving ≥ 50% pain reduction, change in visual analog scale (VAS) scores, change in EQ-5D-5 L utility scores, and incidence of adverse events. Treatments were ranked using the surface under the cumulative ranking curve (SUCRA), and contribution plots were used to assess the strength and source of evidence. HF-SCS had the highest probability of achieving ≥ 50% pain reduction (SUCRA = 78.3%), with significantly greater efficacy than CMM (OR = 2.70, 95% CrI: 1.84-3.56). Indirect comparison suggested a trend favoring HF-SCS over BurstDR-SCS, though this estimate should be interpreted with caution given the absence of direct comparative trials and limited BurstDR-SCS data. LF-SCS also demonstrated superiority over CMM. HF-SCS yielded the greatest reduction in VAS scores (MD = - 6.06, 95% CrI: -7.17 to - 4.95) and showed the largest improvement in EQ-5D-5 L scores (MD = 0.36, 95% CrI: 0.10-0.62). Adverse event rates were comparable across all modalities, with no significant differences observed. Notably, all efficacy and quality-of-life outcomes reported in this analysis were assessed exclusively at the 6-month follow-up time point; the durability of these treatment effects beyond 6 months remains uncertain. High-frequency spinal cord stimulation was associated with the highest probability of achieving superior pain relief and quality-of-life improvement compared to low-frequency and burst stimulation based on indirect evidence derived exclusively from 6-month follow-up data; however, the absence of direct head-to-head trials, the limited BurstDR-SCS data, and the lack of long-term follow-up beyond 6 months preclude definitive conclusions regarding the sustained relative superiority of any modality. Furthermore, placebo and non-specific effects inherent to unblinded device trials cannot be excluded as contributors to the observed treatment effects. These findings support HF-SCS as a promising neuromodulation strategy for this population, pending confirmation in longer-term, sham-controlled comparative trials.