10-kHz Spinal Cord Stimulation Treatment for Painful Diabetic Neuropathy: Results from Post-Hoc Analysis of the SENZA-PPN Study

Figures & data

Figure 1. A total of nine subjects met the study criteria and underwent a trial stimulation, eight were implanted with permanent devices and seven received stimulation through the final follow-up visit at 12 months.

IPG: Implantable pulse generator.

Table 1. Demographic and baseline clinical characteristics of subjects who had trial stimulations.

Characteristics	Subjects (n = 9)
Gender, n (%)
– Females	4 (44%)
– Males	5 (56%)
Age (years) at enrollment
– Mean ± SD	64.8 ± 8.8
– Range	47.0–77.0
Years since diagnosis
– Mean ± SD	7.2 ± 5.1
– Range	1.0–16.0
Ethnicity
– Non-Hispanic/Latino	9 (100.0%)
Race, n (%)
– Black/African–American	1 (12%)
– White	8 (89%)
Baseline VAS, mean ± SD	7.9 ± 1.1
Baseline PDI, mean ± SD	40.2 ± 13.1

PDI: Pain disability index; SD: Standard deviation; VAS: Visual analog scale.

Figure 2. Subject-reported pain intensity decreased after the start of 10 kHz SCS and remained low for the duration of the study.

(A) Mean VAS scores are plotted against follow-up time. (B) Responder and remitter rates after 3, 6 and 12 months of stimulation. (C) Percentage pain relief at the 3-month follow-up shows seven of the eight subjects were responders (≥50%).

SCS: Spinal cord stimulation; VAS: Visual analog scale.

Figure 3. Pain scores reported using the SF-MPQ-2 decreased after 3 and 12 months of stimulation both overall and in each of the four pain subdomains.

Figure 4. Neurological assessments showed improvements in some subjects’ sensation and reflexes.

(A) The neurological status of all subjects who received permanent implants was either improved or maintained after trial stimulation and after 3 or 12 months of stimulation. (B) The majority of improvements were in sensory and reflex functioning.

EoT: End of treatment.

Table 2. Summary of adverse events, their relationship to the study, and severity.

n	Description	Relationship	Severity
1	Pain in extremity (left leg)	Procedure related	Moderate
2	Hematuria	Not related to study	Mild
3	Erectile dysfunction	Not related to study	Mild
4	Implant site seroma	Procedure related	Mild
5	Hepatic failure	Not related to study	Severe
6	Clostridium difficile infection	Not related to study	Mild
7	Abdominal pain	Not related to study	Mild
8	Intra-abdominal hemorrhage	Not related to study	Mild

Figure 5. Other measures of pain and pain interference with daily functioning also show durable improvements with 10 kHz SCS.

(A) Mean PDI scores decreased from baseline levels within 1 month of stimulation and remained low through the study period. (B) GAF scores increased within 1 month of stimulation and remained elevated through the 12-month follow-up. (C) Mean PSQ-3 sleep scores decreased after the initiation of stimulation.

GAF: Global assessment of functioning; PDI: Pain disability index; PSQ-3: Pain and sleep questionnaire; SCS: Spinal cord stimulation.

Figure 6. Improvement in Global Impression of Change following 10 kHz treatment.

Using the Global Impression of Change, both subjects (A) and clinicians (B) reported improvement in nearly all cases.