Critical review of sham surgery clinical trials: Confounding factors analysis

Epothilone B loaded in acellular nerve allograft enhanced sciatic nerve regeneration in rats

BACKGROUND

Epothilone B (EpoB) is a microtubule-stabilizing agent with neuroprotective properties.

OBJECTIVES

This study examines the regenerative properties of ANA supplemented with EpoB on a sciatic nerve deficit in male Wistar rats.

METHODS

For this purpose, the 10 mm nerve gap was filled with acellular nerve allografts (ANAs) containing EpoB at 0.1, 1, and 10 nM concentrations. The sensorimotor recovery was evaluated up to 16 weeks after the operation. Real-time PCR, histomorphometry analysis, and electrophysiological evaluation were also used to evaluate the process of nerve regeneration.

RESULTS

ANA/EpoB (0.1 nM) significantly improved sensorimotor recovery in rats compared to ANA, ANA/EpoB (1 nM), and ANA/EpoB (10 nM) groups. This led to reduced muscle atrophy, improved sciatic functional index, and thermal paw withdrawal reflex latency, indicating nerve regeneration and target organ reinnervation. The electrophysiological and histomorphometry findings also confirmed the ANA/EpoB regenerative properties (0.1 nM). EpoB only enhanced ANA regenerative properties at 0.1 nM, with no therapeutic effects at higher concentrations.

CONCLUSION

Totally, we concluded that ANA loaded with 0.1 nM EpoB can effectively reconstruct the transected sciatic nerve in rats, likely by enhancing axonal sprouting and extension.

Endoscopic sphincterotomy for adults with biliary sphincter of Oddi dysfunction

BACKGROUND

The sphincter of Oddi comprises a muscular complex encircling the distal part of the common bile duct and the pancreatic duct regulating the outflow from these ducts. Sphincter of Oddi dysfunction refers to the abnormal opening and closing of the muscular valve, which impairs the circulation of bile and pancreatic juices.

OBJECTIVES

To evaluate the benefits and harms of any type of endoscopic sphincterotomy compared with a placebo drug, sham operation, or any pharmaceutical treatment, administered orally or endoscopically, alone or in combination, or a different type of endoscopic sphincterotomy in adults with biliary sphincter of Oddi dysfunction.

SEARCH METHODS

We used extensive Cochrane search methods. The latest search date was 16 May 2023.

SELECTION CRITERIA

We included randomised clinical trials assessing any type of endoscopic sphincterotomy versus placebo drug, sham operation, or any pharmaceutical treatment, alone or in combination, or a different type of endoscopic sphincterotomy in adults diagnosed with sphincter of Oddi dysfunction, irrespective of year, language of publication, format, or outcomes reported.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods and Review Manager to prepare the review. Our primary outcomes were: proportion of participants without successful treatment; proportion of participants with one or more serious adverse events; and health-related quality of life. Our secondary outcomes were: all-cause mortality; proportion of participants with one or more non-serious adverse events; length of hospital stay; and proportion of participants without improvement in liver function tests. We used the outcome data at the longest follow-up and the random-effects model for our primary analyses. We assessed the risk of bias of the included trials using RoB 2 and the certainty of evidence using GRADE. We planned to present the results of time-to-event outcomes as hazard ratios (HR). We presented dichotomous outcomes as risk ratios (RR) and continuous outcomes as mean difference (MD) with their 95% confidence intervals (CI).

MAIN RESULTS

We included four randomised clinical trials, including 433 participants. Trials were published between 1989 and 2015. The trial participants had sphincter of Oddi dysfunction. Two trials were conducted in the USA, one in Australia, and one in Japan. One was a multicentre trial conducted in seven US centres, and the remaining three were single-centre trials. One trial used a two-stage randomisation, resulting in two comparisons. The number of participants in the four trials ranged from 47 to 214 (median 86), with a median age of 45 years, and the mean proportion of males was 49%. The follow-up duration ranged from one year to four years after the end of treatment. All trials assessed one or more outcomes of interest to our review. The trials provided data for the comparisons and outcomes below, in conformity with our review protocol. The certainty of evidence for all the outcomes was very low. Endoscopic sphincterotomy versus sham Endoscopic sphincterotomy versus sham may have little to no effect on treatment success (RR 1.05, 95% CI 0.66 to 1.66; 3 trials, 340 participants; follow-up range 1 to 4 years); serious adverse events (RR 0.71, 95% CI 0.34 to 1.46; 1 trial, 214 participants; follow-up 1 year), health-related quality of life (Physical scale) (MD -1.00, 95% CI -3.84 to 1.84; 1 trial, 214 participants; follow-up 1 year), health-related quality of life (Mental scale) (MD -1.00, 95% CI -4.16 to 2.16; 1 trial, 214 participants; follow-up 1 year), and no improvement in liver function test (RR 0.89, 95% CI 0.35 to 2.26; 1 trial, 47 participants; follow-up 1 year), but the evidence is very uncertain. Endoscopic sphincterotomy versus endoscopic papillary balloon dilation Endoscopic sphincterotomy versus endoscopic papillary balloon dilationmay have little to no effect on serious adverse events (RR 0.34, 95% CI 0.04 to 3.15; 1 trial, 91 participants; follow-up 1 year), but the evidence is very uncertain. Endoscopic sphincterotomy versus dual endoscopic sphincterotomy Endoscopic sphincterotomy versus dual endoscopic sphincterotomy may have little to no effect on treatment success (RR 0.65, 95% CI 0.32 to 1.31; 1 trial, 99 participants; follow-up 1 year), but the evidence is very uncertain. Funding One trial did not provide any information on sponsorship; one trial was funded by a foundation (the National Institutes of Diabetes and Digestive and Kidney Diseases, NIDDK), and two trials seemed to be funded by the local health institutes or universities where the investigators worked. We did not identify any ongoing randomised clinical trials.

AUTHORS' CONCLUSIONS

Based on very low-certainty evidence from the trials included in this review, we do not know if endoscopic sphincterotomy versus sham or versus dual endoscopic sphincterotomy increases, reduces, or makes no difference to the number of people with treatment success; if endoscopic sphincterotomy versus sham or versus endoscopic papillary balloon dilation increases, reduces, or makes no difference to serious adverse events; or if endoscopic sphincterotomy versus sham improves, worsens, or makes no difference to health-related quality of life and liver function tests in adults with biliary sphincter of Oddi dysfunction. Evidence on the effect of endoscopic sphincterotomy compared with sham, endoscopic papillary balloon dilation,or dual endoscopic sphincterotomyon all-cause mortality, non-serious adverse events, and length of hospital stay is lacking. We found no trials comparing endoscopic sphincterotomy versus a placebo drug or versus any other pharmaceutical treatment, alone or in combination. All four trials were underpowered and lacked trial data on clinically important outcomes. We lack randomised clinical trials assessing clinically and patient-relevant outcomes to demonstrate the effects of endoscopic sphincterotomy in adults with biliary sphincter of Oddi dysfunction.

Effects of different obesogenic diets on joint integrity, inflammation and intermediate monocyte levels in a rat groove model of osteoarthritis

Introduction: Obesogenic diets aggravate osteoarthritis (OA) by inducing low-grade systemic inflammation, and diet composition may affect OA severity. Here, we investigated the effect of diet on joint damage and inflammation in an OA rat model. Methods: Wistar-Han rats (n = 24) were fed a chow, a high-fat (HF) diet, or a high-fat/high-sucrose (HFS) for 24 weeks. OA was induced unilaterally 12 weeks after the diet onset by groove surgery, and compared to sham surgery or no surgical intervention (contralateral limb). Knee OA severity was determined by OARSI histopathology scoring system. At several timepoints monocyte populations were measured using flow cytometry, and joint macrophage response was determined via CD68 immunohistochemistry staining. Results: Groove surgery combined with HF or HFS diet resulted in higher OARSI scores, and both HF and HFS diet showed increased circulating intermediate monocytes compared to chow fed rats. Additionally, in the HFS group, minimal damage by sham surgery resulted in an increased OARSI score. HFS diet resulted in the largest metabolic dysregulation, synovial inflammation and increased CD68 staining in tibia epiphysis bone marrow. Conclusion: Obesogenic diets resulted in aggravated OA development, even with very minimal joint damage when combined with the sucrose/fat-rich diet. We hypothesize that diet-induced low-grade inflammation primes monocytes and macrophages in the blood, bone marrow, and synovium, resulting in joint damage when triggered by groove OA inducing surgery. When the metabolic dysregulation is larger, as observed here for the HFS diet, the surgical trigger required to induce joint damage may be smaller, or even redundant.

The effect of catheter-based sham renal denervation in hypertension: systematic review and meta-analysis

BACKGROUND

Renal denervation (RDN) has emerged in recent years as a possible treatment for hypertension. The first sham-controlled trial showed a small magnitude and non-significant in the blood pressure (BP) lowering effect, also due to a substantial decrease of BP in sham arm. Considering this, we aimed to quantify the magnitude of BP decrease within the sham arm of Randomized Controlled Trials (RCT) with RDN in patients with hypertension.

METHODS

Electronic databases were searched since inception until January 2022 for randomized sham-controlled trials which assessed the efficacy in lowering BP of the sham intervention for catheter-based RDN in adult patients with hypertension. The outcomes were change in ambulatory/office systolic and diastolic BP.

RESULTS

A total of 9 RCT were included in the analysis enrolling a total of 674 patients. Sham intervention showed a decrease in all evaluated outcomes. Office systolic BP had a reduction of -5.52 mmHg [95%CI -7.91, -3.13] and office diastolic BP of -2.13 mmHg [95%CI -3.08, -1.17]. Sham procedure for RDN also showed a reduction of -3.41 mmHg [95%CI -5.08, -1.75] in ambulatory systolic BP and - 2.44 mmHg [95%CI -3.31, -1.57] in ambulatory diastolic BP.

CONCLUSION

Despite recent data indicating that RDN might be an effective treatment for patients with resistant hypertension when compared to a sham intervention, our results indicate that the sham intervention for RDN also has a significant effect on lowering Office and Ambulatory (24-h) Blood Pressure in adult patients with hypertension. This highlights that BP itself might be sensitive to placebo-like effect and also brings further difficulties in establishing the BP lowering efficacy of invasive interventions due to the magnitude of the sham effect.

Is laparoscopic excision for superficial peritoneal endometriosis helpful or harmful? Protocol for a double-blinded, randomised, placebo-controlled, three-armed surgical trial

INTRODUCTION

Placebo-controlled surgical designs are recommended to ascertain treatment effects for elective surgeries when there is genuine doubt about the effectiveness of the surgery. Some elective surgeries for pain have been unable to show an effect beyond sham surgery, suggesting contributions from contextual factors. However, the nature of contextual factors in elective surgery is largely unexplored. Further, methodological difficulties in placebo-controlled surgical trials impact the ability to estimate the effectiveness of a surgical procedure. These include an overall lack of testing the success of blinding, absence of comparison to a no-surgery control group and dearth of test for neuropathic pain.For women with peritoneal endometriosis, there is uncertainty regarding the pain-relieving effect of surgery. Surgery may put patients at risk of complications such as postsurgical neuropathic pain, without guarantees of sufficient pelvic pain relief. The planned placebo-controlled trial aims to examine the effect of surgery on pelvic pain, widespread pain and neuropathic pain symptoms in women with peritoneal endometriosis, and to test the contribution of contextual factors to pain relief.

METHODS AND ANALYSIS

One hundred women with peritoneal endometriosis will be randomised to either diagnostic laparoscopy with excision of endometrial tissue (active surgery), purely diagnostic laparoscopy (sham surgery) or delayed surgery (no-surgery control group). Outcomes include pelvic pain relief, widespread pain, neuropathic pain symptoms and quality of life. Contextual factors are also assessed. Assessments will be obtained at baseline and 1, 3 and 6 months postrandomisation. Mixed linear models will be used to compare groups over time on all outcome variables.

ETHICS AND DISSEMINATION

The trial is approved by the Regional Ethics Committee in the Central Denmark Region (1-10-72-152-20). The trial is funded by a PhD scholarship from Aarhus University, and supported by a grant from 'Helsefonden' (20-B-0448). Findings will be published in international peer-reviewed journals and disseminated at international conferences.

TRIAL REGISTRATION NUMBER

NCT05162794.

From COVID-19 Pandemic to Patient Safety: A New “Spring” for Telemedicine or a Boomerang Effect?

During the Covid-19 health emergency, telemedicine was an essential asset through which health systems strengthened their response during the critical phase of the pandemic. According to the post-pandemic economic reform plans of many countries, telemedicine will not be limited to a tool for responding to an emergency condition but it will become a structural resource that will contribute to the reorganization of Healthcare Systems and enable the transfer of part of health care from the hospital to the home-based care. However, scientific evidences have shown that health care delivered through telemedicine can be burdened by numerous ethical and legal issues. Although there is an emerging discussion on patient safety issues related to the use of telemedicine, there is a lack of reseraches specifically designed to investigate patient safety. On the contrary, it would be necessary to determine standards and specific application rules in order to ensure safety. This paper examines the telemedicine-risk profiles and proposes a position statement for clinical risk management to support continuous improvement in the safety of health care delivered through telemedicine.

Intra-arterial injection of lidocaine into middle meningeal artery to treat intractable headaches and severe migraine

BACKGROUND AND PURPOSE

We report the results of intra-arterial injection of lidocaine in the middle meningeal artery in patients with intractable headache or status migrainosus.

METHODS

We treated four patients with intra-arterial lidocaine (2 mg/ml) in doses up to 50 mg in each middle meningeal artery via a microcatheter bilaterally (except in one patient). In two patients with intractable headache, the daily maximum intensity of headache (graded by 11-point numeric rating scale) was recorded for 7 days postprocedure. In two patients with status migrainosus, migraine-related disability 3 months prior and after treatment using MIDAS (Migraine Disability Assessment) questionnaire was recorded.

RESULTS

Intra-arterial lidocaine reduced the headache intensity from 8/10 and 10/10 to 0/10 in the two patients with intractable headaches for 2 days (day 0 and day 1) postprocedure. Despite recurrence of headache on day 2, the intensity was less than preprocedure intensity up to the last day recorded (by 3 and 2 points on day 7). In the two patients with status migrainosus, there was immediate reduction in headache intensity following intra-arterial lidocaine. The post treatment 3-month MIDAS score was lower in both patients compared with pretreatment 3-month score; 3 versus 30 and 55 versus 90. Severe disability preprocedure by MIDAS was reduced to little or no disability postprocedure in one patient.

CONCLUSIONS

Intra-arterial lidocaine resulted in amelioration of headache in patients with intractable headache and those with status migrainosus with improvement lasting longer than the short half-life of lidocaine possibly related to central desensitization.

Editorial Commentary: Published Sham Trials in Orthopaedic Surgery Are Flawed and Potentially Unethical-A Wolf in Sheep's Clothing

Sham controlled randomized controlled trials attempt to isolate the beneficial health effects of orthopaedic surgery from benefits due to patients' belief in surgery. The physiological effects of sham surgery, genetic variations that influence responsiveness to placebo, cultural, and geographic influences confound results of these trials. There is a need for high methodological standard for sham-controlled trials as there is potential for direct patient harm and indirect harm from misinformation generated from poorly conducted studies. Confounding factors that affect the reliability of published sham trails expose patients to the potential harm from sham surgery without adequate methodological rigor which could be unethical.

Efficacy and Safety of the Duodeno-Jejunal Bypass Liner in Patients With Metabolic Syndrome: A Multicenter Randomized Controlled Trial (ENDOMETAB)

OBJECTIVE

The aim of this study was to compare the efficacy and safety of 12-month implantation of a duodeno-jejunal bypass liner (DJBL) with conventional medical care in patients with metabolic syndrome (MS).

SUMMARY BACKGROUND DATA

DJBL is an endoscopic device for treating obesity and related disorders. The persistence of favorable results after 6 months has not been tested in a controlled study.

METHODS

We conducted a multicenter randomized controlled trial, stratified by center and diabetes status. The primary endpoint was the remission of MS at 12 months. The secondary endpoints included body mass index (BMI), glucose control, blood pressure, and lipids, assessed at 12 months after implantation, and again, at 12 months after the removal of the DJBL. Up to 174 subjects were planned to be randomized into either the DJBL or the control arm at a 2:1 ratio, respectively. Study enrollment was discontinued by the Scientific Monitoring Committee due to the early termination of the ENDO trial (NCT01728116) by the US Food and Drug Administration. The study was terminated after withdrawal of the device's European Conformity marking by the European Medicines Agency, and an interim analysis was performed.

RESULTS

A total of 82 patients were enrolled (67.5% female, 48.8% with diabetes). At 12 months after randomization, the primary endpoint was met in 6 (12%) DJBL patients and 3 (10%) controls (P = 0.72). Patients in the DJBL group experienced greater BMI loss [mean adjusted difference (95% confidence interval, CI) -3.1 kg/m (-4.4 to -1.9) kg/m, P < 0.001] and HbA1c change [mean adjusted difference -0.5% (95% CI -0.9 to -0.2); P < 0.001] than those in the control group. No difference remained statistically significant at 12 months after the removal of the DJBL. In the DJBL group, 39% of patients experienced at least one device-related serious adverse event, which was classified as Grade III Dindo-Clavien in 22%, and required premature device explantation in 16%.

CONCLUSIONS

The present study showed a transient clinical benefit of DJBL, which was only apparent at 1 year, when the device was still in situ, and was obtained at the risk of serious device-related adverse events in 39% of patients. These results do not support the routine use of DJBL for weight loss and glucose control in patients with MS.

Use of Sham Interventions in Randomized Controlled Trials in Neurosurgery

BACKGROUND

 The use of sham interventions in randomized controlled trials (RCTs) is essential to minimize bias. However, their use in surgical RCTs is rare and subject to ethical concerns. To date, no studies have looked at the use of sham interventions in RCTs in neurosurgery.

METHODS

 This study evaluated the frequency, type, and indication of sham interventions in RCTs in neurosurgery. RCTs using sham interventions were also characterized in terms of design and risk of bias.

RESULTS

 From a total of 1,102 identified RCTs in neurosurgery, 82 (7.4%) used sham interventions. The most common indication for the RCT was the treatment of pain (67.1%), followed by the treatment of movement disorders and other clinical problems (18.3%) and brain injuries (12.2%). The most used sham interventions were saline injections into spinal structures (31.7%) and peripheral nerves (10.9%), followed by sham interventions in cranial surgery (26.8%), and spine surgery (15.8%). Insertion of probes or catheters for a sham lesions was performed in 14.6%.In terms of methodology, most RCTs using sham interventions were double blinded (76.5%), 9.9% were single blinded, and 13.6% did not report the type of blinding.

CONCLUSION

 Sham-controlled RCTs in neurosurgery are feasible. Most aim to minimize bias and to evaluate the efficacy of pain management methods, especially in spinal disorders. The greatest proportion of sham-controlled RCTs involves different types of substance administration routes, with sham surgery the less commonly performed.

Does Sex/Gender Play a Role in Placebo and Nocebo Effects? Conflicting Evidence From Clinical Trials and Experimental Studies

Sex has been speculated to be a predictor of the placebo and nocebo effect for many years, but whether this holds true or not has rarely been investigated. We utilized a placebo literature database on various aspects of the genuine placebo/nocebo response. In 2015, we had extracted 75 systematic reviews, meta-analyses, and meta-regressions performed in major medical areas (neurology, psychiatry, internal medicine). These meta-analyses were screened for whether sex/gender differences had been noted to contribute to the placebo/nocebo effect: in only 3 such analyses female sex was associated with a higher placebo effect, indicating poor evidence for a contribution of sex to it in RCTs. This was updated with another set of meta-analyses for the current review, but did not change the overall conclusion. The same holds true for 18 meta-analyses investigating adverse event (nocebo) reporting in RCT in the placebo arm of trials. We also screened our database for papers referring to sex/gender and the placebo effect in experimental studies, and identified 28 papers reporting 29 experiments. Their results can be summarized as follows: (a) Despite higher sensitivity of pain in females, placebo analgesia is easier to elicit in males; (b) It appears that conditioning is effective specifically eliciting nocebo effects; (c) Conditioning works specifically well to elicit placebo and nocebo effects in females and with nausea; (d) Verbal suggestions are not sufficient to induce analgesia in women, but work in men. These results will be discussed with respect to the question why nausea and pain may be prone to be responsive to sex/gender differences, while other symptoms are less. Lastly, we will discuss the apparent discrepancy between RCT with low relevance of sex, and higher relevance of sex in specific experimental settings. We argue that the placebo response is predominantly the result of a conditioning (learning) response in females, while in males it predominantly may be generated via (verbal) manipulating of expectancies. In RCT therefore, the net outcome of the intervention may be the same despite different mechanisms generating the placebo effect between the sexes, while in experimental work when both pathways are separated and explicitly explored, such differences may surface.