Percutaneous Electrical Neurostimulation (PENS) of Dermatome T6 with an Ambulatory Self-applied Patch vs PENS of Dermatome T6 with Conventional Procedure: Effect on Appetite and Weight Loss in Moderately Obese Patients

Weight Trends After Spinal Cord Stimulation Therapy for Chronic Pain

OBJECTIVES

Spinal cord stimulation (SCS) therapy is an effective treatment for chronic pain, particularly in conditions such as postlaminectomy syndrome and complex regional pain syndrome (CRPS). Rare case reports described significant weight loss in patients who underwent dorsal column SCS therapy for chronic pain. Recently, neuromodulation for obesity has become a novel field for research. We aimed to investigate weight trends among patients treated with SCS for chronic pain.

MATERIALS AND METHODS

We conducted a retrospective chart review in 342 patients treated with SCS or dorsal root ganglion stimulators at our institution between 2010 and 2023. Patients had their weight recorded before SCS implantation and at least once within 12 months after surgery. We also conducted interviews with 28 patients who experienced significant weight loss or had revision procedures owing to weight loss.

RESULTS

We found that 105 of 342 patients (30.7%) experienced weight loss of ≥5% within a year of implantation, and 32 of 105 (30.5%, 9.4% of all patients) experienced weight loss of ≥ 10%. A multivariate regression analysis revealed a modest increase in the likelihood of weight loss among patients with CRPS (odds ratio [OR] = 1.17, 95% CI [1.04, 1.30], p = 0.007) and in those who achieved pain relief after implantation (OR = 1.22, 95% CI [1.05,1.40], p = 0.008). Of the 28 patients with significant weight loss who were interviewed, 12 (43%) could not explain the reasons for their weight loss, whereas eight (29%) reported decreased appetite. Leads placed at higher thoracic levels were associated with increased rates of weight loss (37.2% at T6-T8 and 22.3% at T8-T10; p = 0.038).

CONCLUSIONS

Our findings suggest that SCS therapy may affect weight in patients with chronic pain. Further studies are needed to investigate the potential role of SCS in weight modulation.

Vagal Nerve Therapy in the Management of Obesity: A Systematic Review and Meta-Analysis

INTRODUCTION

The vagus nerve has an important role in satiety, metabolism, and autonomic control in upper gastrointestinal function. However, the role and effects of vagal nerve therapy on weight loss remain controversial. This systematic review and meta-analysis assessed the effects of vagal nerve therapy on weight loss, body mass index (BMI), and obesity-related conditions.

METHODS

MEDLINE, EMBASE, and CINAHL databases were searched for studies up to April 2022 that reported on percentage excess weight loss (%EWL) or BMI at 12 months or remission of obesity-related conditions following vagal nerve therapy from January 2000 to April 2022. Weighted mean difference (WMD) was calculated, meta-analysis was performed using random-effects models, and between-study heterogeneity was assessed.

RESULTS

Fifteen studies, of which nine were randomised controlled trials, of 1,447 patients were included. Vagal nerve therapy led to some improvement in %EWL (WMD 17.19%; 95% confidence interval [CI]: 10.94-23.44; p < 0.001) and BMI (WMD -2.24 kg/m2; 95% CI: -4.07 to -0.42; p = 0.016). There was a general improvement found in HbA1c following vagal nerve therapy when compared to no treatment given. No major complications were reported.

CONCLUSIONS

Vagal nerve therapy can safely result in a mild-to-moderate improvement in weight loss. However, further clinical trials are required to confirm these results and investigate the possibility of the long-term benefit of vagal nerve therapy as a dual therapy combined with standard surgical bariatric interventions.

A systematic review on neuromodulation therapies for reducing body weight in patients with obesity

The global prevalence of obesity increases yearly along with a rising demand for efficacious, safe, and accessible treatments. Neuromodulation interventions (i.e., deep brain stimulation [DBS], transcranial magnetic stimulation [TMS], transcranial direct current stimulation [tDCS], percutaneous neurostimulation [PENS], vagus nerve stimulation [VNS], and gastric electrical stimulation [GES]) have been proposed as novel therapies. This systematic review sought to examine the safety and efficacy of neuromodulation therapies in reducing body weight in patients with obesity. Using PRISMA guidelines, we performed a systematic review for studies on neuromodulation for the treatment of obesity, resulting in 60 trials included (7 DBS, 5 TMS, 7 tDCS, 17 PENS and VNS, and 24 GES; a total of 3,042 participants). While promising results have been reported in open label studies, double-blinded randomized clinical trials often did not reach their primary endpoints, with no technique inducing a striking reduction in body weight. Bearing in mind the complexity and multifactorial nature of obesity, it is possible that a single treatment may not be enough for patients to lose or maintain the weight lost at long term.

Addition of Probiotics to Anti-Obesity Therapy by Percutaneous Electrical Stimulation of Dermatome T6. A Pilot Study

Obesity is becoming a pandemic and percutaneous electrical stimulation (PENS) of dermatome T6 has been demonstrated to reduce stomach motility and appetite, allowing greater weight loss than isolated hypocaloric diets. However, modulation of intestinal microbiota could improve this effect and control cardiovascular risk factors. Our objective was to test whether addition of probiotics could improve weight loss and cardiovascular risk factors in obese subjects after PENS and a hypocaloric diet. A pilot prospective study was performed in patients (n = 20) with a body mass index (BMI) > 30 kg/m2. Half of them underwent ten weeks of PENS in conjunction with a hypocaloric diet (PENS-Diet), and the other half was treated with a PENS-Diet plus multistrain probiotics (L. plantarum LP115, B. brevis B3, and L. acidophilus LA14) administration. Fecal samples were obtained before and after interventions. The weight loss and changes in blood pressure, glycemic and lipid profile, and in gut microbiota were investigated. Weight loss was significantly higher (16.2 vs. 11.1 kg, p = 0.022), whereas glycated hemoglobin and triglycerides were lower (-0.46 vs. -0.05%, p = 0.032, and -47.0 vs. -8.5 mg/dL, p = 0.002, respectively) in patients receiving PENS-Diet + probiotics compared with those with a PENS-Diet. Moreover, an enrichment of anti-obesogenic bacteria, including Bifidobacterium spp, Akkermansia spp, Prevotella spp, and the attenuation of the Firmicutes/Bacteroidetes ratio were noted in fecal samples after probiotics administration. In obese patients, the addition of probiotics to a PENS intervention under a hypocaloric diet could further improve weight loss and glycemic and lipid profile in parallel to the amelioration of gut dysbiosis.