Sacral nerve stimulation for constipation: long-term outcomes

Meta-analysis of Randomized Controlled Trials on the Efficacy of Sacral Neuromodulation in Chronic Constipation

OBJECTIVES

The present systematic review aimed to assess the outcome of sacral neuromodulation (SNM) in adult patients with chronic constipation.

MATERIALS AND METHODS

A systematic review of randomized controlled trials (RCTs) that assessed the efficacy of SNM in chronic constipation was conducted and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guideline. PubMed, Scopus, and Web of Science were screened from their inception through March 2024. The primary outcome was improvement in constipation and quality of life (QoL), and the secondary outcome was adverse events after treatment. The risk of bias and certainty of evidence were assessed by the risk of bias 2 tool and Grading of Recommendations Assessment, Development, and Evaluation approach.

RESULTS

Five RCTs incorporating 187 patients (93.6% female) with a median age of 42.5 years were included; 154 patients underwent SNM whereas 86 patients were crossed over to sham stimulation, and 33 received conservative treatment, amounting to a control group of 119 patients. The odds of relief of constipation after SNM were similar to those in the control group in the random-effect model (odds ratio [OR]: 1.92, 95% CI: 0.68-5.42, p = 0.217). The median percentage of reduction in the Cleveland Clinic Florida/Wexner Constipation Score was 27.9% in the SNM group vs 18.4% in the control group. No significant differences were observed in QoL. Both groups had similar odds of adverse events (OR: 2.22, 95% CI: 0.19-25.53, p = 0.521).

CONCLUSION

Although a relatively safe treatment, SNM was not associated with any tangible improvements in either constipation or QoL.

Sacral Neuromodulation Versus Conservative Treatment for Refractory Idiopathic Slow-transit Constipation: The Randomized Clinical No.2-Trial

OBJECTIVE

Assess the effectiveness of sacral neuromodulation (SNM) versus personalized conservative treatment (PCT) in patients with refractory idiopathic slow-transit constipation (STC).

BACKGROUND

Evidence on SNM for idiopathic STC is conflicting and of suboptimal methodological quality.

METHODS

The No.2-Trial was a multicenter, open-label, pragmatic, randomized trial performed in 2 Dutch hospitals. Sixty-seven patients with idiopathic STC, a defecation frequency <3 per week and refractory (ie, unresponsive) to maximal conservative (nonoperative) treatment were included. Exclusion criteria included outlet obstruction, rectal prolapse, and previous colon surgery. Patients were randomized (3:2) to SNM (n=41) or PCT (n=26) with randomization minimization between February 21, 2017 and March 12, 2020. In SNM patients, an implantable pulse generator was implanted after a successful 4-week test stimulation. PCT patients received conservative treatment such as laxatives or retrograde colonic irrigation. The primary outcome was treatment success (defined as average defecation frequency ≥3 per week) after 6 months. Secondary outcomes included constipation severity, fatigue, quality of life, and adverse events. Analysis was according to intention-to-treat.

RESULTS

After 6 months, 22 (53.7%) patients were successfully treated with SNM versus 1 (3.8%) patient with PCT (odds ratio 36.4, 95% CI 3.4-387.5, P =0.003). At 6 months, SNM patients reported lower constipation severity and fatigue scores ( P <0.001) and improved quality of life compared with PCT ( P <0.001). Eight serious adverse events (6 SNM, 2 PCT) and 78 adverse events (68 SNM, 10 PCT) were reported.

CONCLUSIONS

SNM is a promising surgical treatment option in a homogeneous group of adults and adolescents with refractory idiopathic STC. No.2-Trial registered at ClinicalTrials.gov NCT02961582.

Sacral neuromodulation for constipation and fecal incontinence in children and adolescents - study protocol of a prospective, randomized trial on the application of invasive vs. non-invasive technique

BACKGROUND

A therapeutic effect of sacral neuromodulation (SNM) on fecal incontinence (FI) and quality of life has been proven in adults. SNM is, however, rarely used in pediatric cases. The aim of the study is to investigate effects of SNM in pediatric constipation in a prospective parallel-group trial.

METHODS

A monocentric, randomized, unblinded, parallel-group trial is conducted. SNM is conducted in the invasive variant and in an innovative, external approach with adhesive electrodes (enteral neuromodulation, ENM). We include patients with constipation according to the ROME IV criteria and refractory to conventional options. Patients with functional constipation and Hirschsprung's disease are able to participate. Participants are allocated in a 1:1 ratio to either SNM or ENM group. Clinical data and quality of life is evaluated in regular check-ups. Neuromodulation is applied continuously for 3 months (end point of the study) with follow-up-points at 6 and 12 months. Findings are analyzed statistically considering a 5% significance level (p ≤ 0.05). Outcome variables are defined as change in (1) episodes of abdominal pain, (2) episodes of FI, (3) defecation frequency, (4) stool consistency. Improvement of proprioception, influence on urinary incontinence, quality of life and safety of treatment are assessed as secondary outcome variables. We expect a relevant improvement in both study groups.

DISCUSSION

This is the first trial, evaluating effects of neuromodulation for constipation in children and adolescents and comparing effects of the invasive and non-invasive application (SNM vs. ENM).

TRIAL REGISTRATION

The study is registered with clinicaltrials.gov, Identifier NCT04713085 (date of registration 01/14/2021).

Effectiveness, safety and cost-effectiveness of sacral neuromodulation for idiopathic slow-transit constipation: a systematic review

AIM

Sacral neuromodulation (SNM) is a minimally invasive treatment option for functional constipation. Evidence regarding its effectiveness is contradictory, driven by heterogeneous study populations and designs. The aim of this study was to assess the effectiveness, safety and cost-effectiveness of SNM in children and adults with refractory idiopathic slow-transit constipation (STC).

METHOD

OVID Medline, OVID Embase, Cochrane Library, the KSR Evidence Database, the NHS Economic Evaluation Database and the International HTA Database were searched up to 25 May 2023. For effectiveness outcomes, randomized controlled trials (RCTs) were selected. For safety outcomes, all study designs were selected. For cost-effectiveness outcomes, trial- and model-based economic evaluations were selected for review. Study selection, risk of bias and quality assessment, and data extraction were independently performed by two reviewers. For the intervention 'sacral neuromodulation' effectiveness outcomes included defaecation frequency and constipation severity. Safety and cost-effectiveness outcomes were, respectively, adverse events and incremental cost-effectiveness ratios.

RESULTS

Of 1390 records reviewed, 67 studies were selected for full-text screening. For effectiveness, one cross-over and one parallel-group RCT was included, showing contradictory results. Eleven studies on safety were included (four RCTs, three prospective cohort studies and four retrospective cohort studies). Overall infection rates varied between 0% and 22%, whereas reoperation rates varied between 0% and 29%. One trial-based economic evaluation was included, which concluded that SNM was not cost-effective compared with personalized conservative treatment at a time horizon of 6 months. The review findings are limited by the small number of available studies and the heterogeneity in terms of study populations, definitions of refractory idiopathic STC and study designs.

CONCLUSION

Evidence for the (cost-)effectiveness of SNM in children and adults with refractory idiopathic STC is inconclusive. Reoperation rates of up to 29% were reported.

Technical and functional outcome after sacral neuromodulation using the "H" technique

BACKGROUND

Sacral neuromodulation (SNM) is a widely accepted treatment for pelvic floor disorders, including constipation and fecal incontinence (FI). In 2017, a standardized electrode placement method, the H technique, was introduced to minimize failure rates and improve clinical outcomes. We aimed to investigate the technical feasibility and functional outcome of the procedure.

METHODS

In this prospective study, we evaluated the first 50 patients who underwent SNM according to the H technique between 2017 and 2020 at a tertiary care hospital. Patient demographic and clinical data were collected, and the impact of various factors on patients' postoperative quality of life (QoL) was assessed after a follow-up of 40 months. Functional outcome was monitored prospectively using a standardized questionnaire.

RESULTS

Of 50 patients, 36 (72%) reported greater than 50% symptom relief and received a permanent implant (95% CI: 58.3-82.5). We observed 75% success in relieving FI (95% CI: 58.9-86.3) and 64% in constipation (95% CI: 38.8-83.7). Complication occurred in five (10%) patients. Preoperative vs. postoperative physical and psychological QoL, Vaizey score, and obstructed defecation syndrome (ODS) scores revealed significant improvements (all p < 0.01). Male gender was significantly associated with postoperative complications (p = 0.035).

CONCLUSION

We provide evidence for the technical feasibility and efficacy of the SNM implantation using the H technique. The medium-term results are promising for patients with FI and constipation. Male patients and those with a BMI > 25 are more prone to perioperative complications.

[Sacral Neuromodulation for Fecal Incontinence and Constipation: Evidence, Programming and Long-term Management]

BACKGROUND

Over the last two decades, sacral neuromodulation (SNM) has established its role in the treatment of functional pelvic organ-/pelvic floor disorders. Even though the mode of action is not fully understood, SNM has become the preferred surgical treatment of fecal incontinence.

METHODS AND RESULTS

A literature search was carried out on programming sacral neuromodulation and long-term outcomes in treating fecal incontinence and constipation.Sacral neuromodulation was found to be successful in the long term. Over the years, the spectrum of indications has expanded, and now includes patients presenting with anal sphincter lesions. The use of SNM for low anterior resection syndrome (LARS) is currently under clinical investigation. Findings of SNM for constipation are less convincing. In several randomised crossover studies, no success was demonstrated, even though it is possible that subgroups may benefit from the treatment. Currently the application cannot be recommended in general.The pulse generator programming sets the electrode configuration, amplitude, pulse frequency and pulse width. Usually pulse frequency and pulse width follow a default setting (14 Hz, 210 s), while electrode configuration and stimulation amplitude are adjusted individually to the patient need and perception of stimulation.Despite low infection rates and few electrode-/pulse generator dysfunctions, up to 65% of patients require surgical reintervention during long term follow-up - in 50% of cases because of battery depletion, which is an expected event. At least one reprogramming is necessary in about 75% of the patients during the course of the treatment, mostly because of changes in effectiveness, but rarely because of pain. Regular follow-up visits appear to be advisable.

CONCLUSION

Sacral neuromodulation can be considered to be a safe and effective long-term therapy of fecal incontinence. To optimise the therapeutic effect, a structured follow-up regime is advisable.

Effect of transcutaneous abdominal electrical stimulation in people with constipation due to spinal cord injuries: a pilot study

OBJECTIVE

To evaluate the effect of abdominal electrical stimulation (EE) on bowel movement frequency and feces consistency and expelled amount in people with constipation due to spinal cord injuries (SCI).

METHOD

This is an experimental, crossover, randomized pilot study with two treatment groups: conventional intestinal rehabilitation and conventional rehabilitation associated with EE via 8- and 20-Hz Functional Electrical Stimulation (FES) of the abdominal muscles. Both groups were followed for two weeks with daily 30-minute EE sessions. Participants were hospitalized in a rehabilitation institute in the municipality of São Paulo. Data were analyzed using descriptive and inferential statistics.

RESULTS

This study included 10 people with SCI, of which most were male (70%), with a mean age of 39 years (SD = 16.37). EE, associated with conventional treatment, was more effective in increasing defecation frequency (p = 0.029) and amount of feces expelled (p = 0.031).

CONCLUSION

Abdominal EE, associated with conventional treatment, helped to increase defecation frequency and amount of feces expelled in people with constipation due to SCI. This pilot study will serve as the basis for a future clinical trial with greater sampling and statistical evidence.

Efeito da eletroestimulação abdominal transcutânea no quadro de constipação em pessoas com lesão medular: estudo piloto

RESUMO Objetivo: Avaliar o efeito da eletroestimulação (EE) abdominal sobre a frequência de evacuações, a consistência e a quantidade de fezes em pessoas com constipação decorrente da lesão medular (LM). Método: Estudo piloto experimental do tipo crossover-randomizado em dois grupos de tratamento: convencional de reabilitação intestinal e convencional associado à EE com Functional Electrical Stimulation (FES) de 8 e 20 Hz aplicados na musculatura abdominal. Ambos os grupos em seguimento por duas semanas, com 30 minutos de sessão diária de EE. Os participantes estavam internados em um instituto de reabilitação da cidade de São Paulo. Os dados foram analisados por meio de estatística descritiva e inferencial. Resultados: Participaram do estudo 10 pessoas com LM, a maioria do sexo masculino (70%), com média de idade de 39 anos (DP = 16,37). A EE, associada ao tratamento convencional, mostrou-se mais eficaz no aumento da frequência evacuatória (p = 0,029) e na quantidade de fezes (p = 0,031). Conclusão: A EE abdominal associada ao tratamento convencional auxiliou no aumento da frequência evacuatória e na quantidade de fezes no quadro de constipação em pessoas com LM. Este estudo piloto servirá como base para um futuro ensaio clínico com maior amostragem e comprovação estatística.

The role of neuromodulation in chronic functional constipation: a systematic review

BACKGROUND

Chronic functional constipation is a highly prevalent disorder in which, when conservative measures fail to relieve symptoms, surgical interventions are sometimes indicated. In recent years, neuromodulation for the treatment of functional constipation has gained interest but its role and effectiveness are still unclear. The purpose of this review is to provide a systematic overview on the current literature on the different modalities of neurostimulation and their effect on chronic functional constipation in adults as reported in the literature.

METHODS

A search in the literature for articles concerning the effect of different types of neuromodulation on constipation was performed in PubMed using extensive search terms for the different modalities of neuromodulation. Studies and trials were checked for eligibility. For all types of neuromodulation together, 27 articles were included.

RESULTS

17 studies were included on SNM (sacral nerve modulation). Although multiple studies show positive results on the effect of SNM in constipation, double-blind crossover RCT's (randomised controlled trials) showed no significant effect. 3 studies were included for tSNS (transcutaneous sacral nerve stimulation), 2 for PTNS (percutaneous tibial nerve stimulation) and 2 for TTNS (transcutaneous tibial nerve stimulation). Studies and trials on these modalities of neuromodulation reported ambiguous results on statistical significance of the effect. For transcutaneous IFC (interferential current therapy) 2 studies were included, which both reported a statistically significant effect on all outcomes.

CONCLUSION

The beneficial effect of neuromodulation in chronic functional constipation remains questionable. However, neuro-modulation might be worth considering in patients refractory to treatment before turning to more invasive measures. Future research should shed more light on the effects of neuromodulation in constipation.

Effects of temporary sacral nerve stimulation on gastrointestinal motility and function in patients with chronic refractory slow-transit constipation

BACKGROUND

The efficacy of sacral nerve stimulation (SNS) on patients with chronic refractory slow-transit constipation is controversial and its mechanism of action on gastrointestinal motility and transit is not fully understood. The aim of this study was to document the effects of temporary SNS on the gastrointestinal and biliary tract motility and on gastrointestinal transit in patients with refractory slow-transit constipation.

METHODS

This was a prospective interventional study. Patients with slow-transit chronic constipation, unresponsive to any conservative treatment, were enrolled between January 2013 and December 2018. Patients' quality of life [patient assessment of constipation quality of life (PAC-QOL) questionnaire], constipation scores (Cleveland Clinic Constipation Score) colonic transit time (CTT), orocecal transit time (OCTT), gastric and gallbladder kinetics, together with the assessment of the autonomic nerve function were evaluated before and during temporary SNS.

RESULTS

14 patients (12 females, median age 38 years, range 24-42 years) had temporary SNS. The Cleveland Clinic Constipation Score did not change compared to baseline (23 ± 3 vs 21.4; p = 070). The PAC-QOL did not improve significantly during the stimulation period. Gallbladder/stomach motility (half-emptying time) did not change significantly before and after SNS. OCTT was delayed at baseline, as compared to standard internal normal values, and did not change during SNS. CTT did not improve significantly, although in two patients it decreased substantially from 97 to 53 h, and from 100 to 65 h.

CONCLUSIONS

Temporary SNS did not have any effect on upper/lower gastrointestinal motility and transit in patients with severe constipation.

Optimizing sacral neuromodulation for low anterior resection syndrome: learning from our experience

AIM

The aim of this work was to review our institutional series of patients treated with sacral neuromodulation (SNM) for low anterior resection syndrome (LARS) and evaluate possible factors associated with therapeutic success.

METHOD

Twenty-five patients were treated with SNM for LARS between 2008 and 2019. SNM was performed as per our institutional protocol. Patients were evaluated with Wexner and LARS scores before and after SNM treatment. A visual analogue scale (1-10) was used to evaluate overall patient satisfaction with SNM.

RESULTS

There were significant differences between the mean LARS score values before (37.82) and after (29) SNM therapy (P < 0.004). The mean Wexner score was higher (16.24) before SNM treatment than afterwards (11.13) (P < 0.004). There was a direct relationship between the height of anastomosis and LARS score (P = 0.035): there were big changes in LARS scoring (pre-/post-SNM therapy) in patients with higher anastomoses, and vice versa. Patients who received radiotherapy scored lower in mean satisfaction (6.38) than patients without previous radiotherapy (8.22) (P = 0.008). There was an important positive association between Wexner score and patient satisfaction (P = 0.001): relevant changes in Wexner scoring after SNM therapy were associated with high patient satisfaction, and vice versa.

CONCLUSION

Our study showed a relationship between changes in Wexner and LARS scores before and after SNM and overall patient satisfaction with SNM therapy. These findings also suggest patients with previous radiotherapy may have worse results with SNM (based on lower overall satisfaction), and that higher anastomoses have a greater impact on the post-SNM LARS score.

Evaluation and Treatment of Constipation in the Geriatric Population

Chronic constipation affects one-third of the US population and occurs disproportionately in the elderly and female individuals, increasing in older individuals who are institutionalized. This condition has a significant impact on health care costs and quality of life. Clinicians need to consider primary as well as secondary causes of constipation in elderly individuals because the cause is often multifactorial. Diagnostic algorithms should eliminate red-flag symptoms that may indicate a malignancy but also consider pelvic floor dysfunction, which is more common in this age group. An appropriate treatment plan is tailored to the severity of the patient's symptoms.

Comparison of long-term outcome of sacral nerve stimulation for constipation and faecal incontinence with focus on explantation rate, additional visits, and patient satisfaction

BACKGROUND

The aim of the present study was to compare sacral nerve stimulation (SNS) for constipation (SNS-C) with SNS for idiopathic faecal incontinence (SNS-IFI) regarding explantation rate, additional visits, and improvement of patient satisfaction 5 years after implantation.

METHODS

From our prospective database (launched in 2009), we extracted all SNS-C patients 5 years post-implantation, and the SNS-IFI patients implanted just before and just after each SNS-C patient. We retrospectively evaluated the explantation rate, number of additional visits, and patient satisfaction using a visual analogue scale (VAS). We hypothesized that compared with those in the SNS-IFI group: (1) the explantation rate would be higher in SNS-C patients, (2) the number of additional visits would be higher in SNS-C patients, and (3) in patients with an active implant at 5 years, the improvement in VAS would be the same.

RESULTS

We included 40 SNS-C patients and 80 SNS-IFI patients. In the SNS-C group 7/40 (17.5%), patients were explanted, compared to 10/80 (12.5%) patients in the SNS-IFI group (p = 0.56). The mean number of additional visits in the SNS-C group was 3.5 (95% CI 2.8-4.1)) and 3.0 (95% CI 2.6-3.6)) in the SNS-IFI group (p = 0.38). Additional visits due to loss of efficacy were significantly higher in the SNS-C patients (p = 0.03). The reduction in VAS score (delta VAS) at 5 years was 37.1 (95% CI 20.9-53.3) in the SNS-C group, and 46.0 (95% CI 37.9-54.0) in the SNS-IFI group (p = 0.27).

CONCLUSIONS

No significant difference was found regarding explantation rate, number of additional visits, or improvement of VAS at 5 years after SNS implantation between SNS-C patients and SNS-IFI patients.

The Effectiveness of Acupuncture in Management of Functional Constipation: A Systematic Review and Meta-Analysis

OBJECTIVE

The purpose of this study was to assess the effectiveness and safety of acupuncture for functional constipation (FC).

METHODS

A rigorous literature search was performed in English (PubMed, Web of Science, the Cochrane Library, and EMBASE) and Chinese (China National Knowledge Infrastructure (CNKI), Chinese Biological Medical (CBM), Wanfang database, and China Science and Technology Journal (VIP)) electronic databases from their inception to October 2019. Included randomized controlled trials (RCTs) compared acupuncture therapy with sham acupuncture or pharmacological therapies. The outcome measures were evaluated, including the primary outcome of complete spontaneous bowel movement (CSBM) and secondary outcomes of Bristol Stool Form Scale (BSFS), constipation symptoms scores (CSS), responder rate, the Patient Assessment of Constipation Quality of Life (PAC-QOL) questionnaire, and safety evaluation. Meta-analysis was performed by using RevMan5.3.

RESULTS

The merged data of 28 RCTs with 3525 participants indicated that acupuncture may be efficient for FC by increasing CSBMs (p < 0.00001; MD = 0.84 [95% CI, 0.65 to 1.03]; I 2 = 0%) and improving constipation symptoms (p=0.03; SMD = -0.4 [95% CI, -0.78 to -0.03]; I 2 = 74%), stool formation (p < 0.00001; MD = 0.24 [95% CI, 0.15 to 0.34]; I 2 = 0%), quality of life (p < 0.00001; N = 1, MD = -0.33 [95% CI, -0.45 to -0.21]), and responder rates (p=0.02; RR = 2.16; [95% CI, 1.1 to 4.24]; I 2 = 69%) compared with the effects of sham treatment. No increased risk of adverse events was observed (p=0.44; RR = 1.18; [95% CI, 0.77 to 1.81]; I 2 = 0%). With regard to medication comparisons, the pooled data indicated that acupuncture was more effective in increasing CSBMs (p=0.004; MD = 0.53 [95% CI, 0.17 to 0.88]; I 2 = 88%) and improving patients' quality of life (p < 0.00001; SMD = -0.73 [95% CI, -1.02 to -0.44]; I 2 = 64%), with high heterogeneity. However, there were no significant differences in responder rate (p=0.12; RR = 1.31; [95% CI, 0.94 to 1.82]; I 2 = 53%), BSFS (p=0.5; MD = 0.17 [95% CI, -0.33 to 0.68]; I 2 = 93%), or CSS (p=0.05; SMD = -0.62 [95% CI, -1.23 to -0.01]; I 2 = 89%). Regarding safety evaluation, acupuncture was safer than medications (p < 0.0001; RR = 0.3; [95% CI, 0.18 to 0.52]; I 2 = 30%).

CONCLUSIONS

Current evidence suggests that acupuncture is an efficient and safe treatment for FC. Acupuncture increased stool frequency, improved stool formation, alleviated constipation symptoms, and improved quality of life. However, the evidence quality was relatively low and the relationship between acupuncture and drugs is not clear. More high-quality trials are recommended in the future. PROSPERO registration number: CRD42019143347.