Inter-rater reliability of risk of bias tools for non-randomized studies

PURPOSE

There is limited knowledge on the reliability of risk of bias (ROB) tools for assessing internal validity in systematic reviews of exposure and frequency studies. We aimed to identify and then compare the inter-rater reliability (IRR) of six commonly used tools for frequency (Loney scale, Gyorkos checklist, American Academy of Neurology [AAN] tool) and exposure (Newcastle-Ottawa scale, SIGN50 checklist, AAN tool) studies.

METHODS

Six raters independently assessed the ROB of 30 frequency and 30 exposure studies using the three respective ROB tools. Articles were rated as low, intermediate, or high ROB. We calculated an intraclass correlation coefficient (ICC) for each tool and category of ROB tool. We compared the IRR between ROB tools and tool type by inspection of overlapping ICC 95% CIs and by comparing their coefficients after transformation to Fisher's Z values. We assessed the criterion validity of the AAN ROB tools by calculating an ICC for each rater in comparison with the original ratings from the AAN.

RESULTS

All individual ROB tools had an IRR in the substantial range or higher (ICC point estimates between 0.61 and 0.80). The IRR was almost perfect (ICC point estimate > 0.80) for the AAN frequency tool and the SIGN50 checklist. All tools were comparable in IRR, except for the AAN frequency tool which had a significantly higher ICC than the Gyorkos checklist (p = 0.021) and trended towards a higher ICC when compared to the Loney scale (p = 0.085). When examined by category of ROB tool, scales, and checklists had a substantial IRR, whereas the AAN tools had an almost perfect IRR. For the criterion validity of the AAN ROB tools, the average agreement between our raters and the original AAN ratings was moderate.

CONCLUSION

All tools had substantial IRRs except for the AAN frequency tool and the SIGN50 checklist, which both had an almost perfect IRR. The AAN ROB tools were the only category of ROB tools to demonstrate an almost perfect IRR. This category of ROB tools had fewer and simpler criteria. Overall, parsimonious tools with clear instructions, such as those from the AAN, may provide more reliable ROB assessments.

Screening for cognitive impairment in adults with sickle cell disease: A systematic review and meta-analysis

Neurovascular disease such as symptomatic stroke, silent brain infarcts and vascular cognitive impairment are common complications of sickle cell disease (SCD) that can have devastating consequences on quality of life, employment, and social functioning.  Early recognition of neurovascular disease is a prerequisite for the timely optimization of medical care and to connect patients to adaptive resources. While cognitive impairment has been well described in children, currently available data are limited in adults. As a result, guidance on the optimal cognitive screening strategies in adults is scarce. We conducted a systematic review to identify the different screening tools that have been evaluated in SCD. A meta-analysis was performed to estimate the prevalence of suspected cognitive impairment in this population. In this qualitative synthesis, we present 8 studies that evaluated 6 different screening tools. Patient characteristics that impacted on cognitive screening performance included age, education level, and a prior history of stroke. We report a pooled prevalence of 38% [14-62%] of suspected cognitive impairment. We discuss the relative benefits and limitations of the different screening tools to help clinicians select an adapted approach tailored to their specific patients' needs. Further studies are needed to establish and validate cognitive screening strategies in patients with diverse cultural and educational backgrounds.

Numb Chin Syndrome in Sickle Cell Disease: A Systematic Review and Recommendations for Investigation and Management

Numb chin syndrome (NCS) is a rare sensory neuropathy resulting from inferior alveolar or mental nerve injury. It manifests as hypoesthesia, paraesthesia, or, rarely, as pain in the chin and lower lip. Several case reports suggest that sickle cell disease (SCD) could be a cause of NCS. However, information about NCS is scarce in this population. Our objectives were to synthesize all the available literature relevant to NCS in SCD and to propose recommendations for diagnosis and management based on the best available evidence. A systematic review was performed on several databases to identify all relevant publications on NCS in adults and children with SCD. We identified 73 publications; fourteen reports met the inclusion/exclusion criteria. These described 33 unique patients. Most episodes of NCS occurred in the context of typical veno-occlusive crises that involved the mandibular area. Radiological signs of bone infarction were found on some imaging, but not all. Neuropathy management was mostly directed toward the underlying cause. Overall, these observations suggest that vaso-occlusion and bone infarction could be important pathophysiological mechanisms of NCS. However, depending on the individual context, we recommend a careful evaluation to rule out differential causes, including infections, local tumors, metastatic disease, and stroke.

Non-contrast CT markers of intracerebral hematoma expansion: a reliability study

OBJECTIVES

We evaluated whether clinicians agree in the detection of non-contrast CT markers of intracerebral hemorrhage (ICH) expansion.

METHODS

From our local dataset, we randomly sampled 60 patients diagnosed with spontaneous ICH. Fifteen physicians and trainees (Stroke Neurology, Interventional and Diagnostic Neuroradiology) were trained to identify six density (Barras density, black hole, blend, hypodensity, fluid level, swirl) and three shape (Barras shape, island, satellite) expansion markers, using standardized definitions. Thirteen raters performed a second assessment. Inter- and intra-rater agreement were measured using Gwet's AC₁, with a coefficient > 0.60 indicating substantial to almost perfect agreement.

RESULTS

Almost perfect inter-rater agreement was observed for the swirl (0.85, 95% CI: 0.78-0.90) and fluid level (0.84, 95% CI: 0.76-0.90) markers, while the hypodensity (0.67, 95% CI: 0.56-0.76) and blend (0.62, 95% CI: 0.51-0.71) markers showed substantial agreement. Inter-rater agreement was otherwise moderate, and comparable between density and shape markers. Inter-rater agreement was lower for the three markers that require the rater to identify one specific axial slice (Barras density, Barras shape, island: 0.46, 95% CI: 0.40-0.52 versus others: 0.60, 95% CI: 0.56-0.63). Inter-observer agreement did not differ when stratified for raters' experience, hematoma location, volume, or anticoagulation status. Intra-rater agreement was substantial to almost perfect for all but the black hole marker.

CONCLUSION

In a large sample of raters with different backgrounds and expertise levels, only four of nine non-contrast CT markers of ICH expansion showed substantial to almost perfect inter-rater agreement.

KEY POINTS

• In a sample of 15 raters and 60 patients, only four of nine non-contrast CT markers of ICH expansion showed substantial to almost perfect inter-rater agreement (Gwet's AC₁> 0.60). • Intra-rater agreement was substantial to almost perfect for eight of nine hematoma expansion markers. • Only the blend, fluid level, and swirl markers achieved substantial to almost perfect agreement across all three measures of reliability (inter-rater agreement, intra-rater agreement, agreement with the results of a reference reading).

Neurostimulation in People with Drug-Resistant Epilepsy: Systematic Review and Meta-Analysis from the ILAE Surgical Therapies Commission

OBJECTIVE

Summarize the current evidence on efficacy and tolerability of vagus nerve stimulation (VNS), responsive neurostimulation (RNS), and deep brain stimulation (DBS) through a systematic review and meta-analysis.

METHODS

We followed the PRISMA reporting standards and searched Ovid Medline, Ovid Embase, and the Cochrane Central Register of Controlled Trials. We included published randomized controlled trials (RCT) and their corresponding open-label extension studies, as well as prospective case series, with ≥ 20 participants (excluding studies limited to children). Our primary outcome was the mean (or median when unavailable) percentage decrease in frequency, as compared to baseline, of all epileptic seizures at last follow-up. Secondary outcomes included proportion of treatment responders and proportion with seizure freedom.

RESULTS

We identified 30 eligible studies, six of which were RCTs. At long-term follow-up (mean 1.3 years), five observational studies for VNS reported a pooled mean percentage decrease in seizure frequency of 34.7% (95% CI: -5.1, 74.5). In the open-label extension studies for RNS, the median seizure reduction was 53%, 66%, and 75% at two, five, and nine years of follow-up, respectively. For DBS, the median reduction was 56%, 65%, and 75% at two, five, and seven years, respectively. The proportion of individuals with seizure freedom at last follow-up increased significantly over time for DBS and RNS while a positive trend was observed for VNS. Quality of life was improved in all modalities. The most common complications included hoarseness, cough and throat pain for VNS and implant site pain, headache, and dysesthesia for DBS and RNS.

SIGNIFICANCE

Neurostimulation modalities are an effective treatment option for drug resistant epilepsy, with improving outcomes over time and few major complications. Seizure reduction rates among the three therapies were similar during the initial blinded phase. Recent long-term follow-up studies are encouraging for RNS and DBS but are lacking for VNS.

Diagnosis and Management of Central Nervous System Demyelinating Disorders

The spectrum of demyelinating diseases affecting the central nervous system is broad. Although many have a chronic course, neuroinflammatory conditions often present with acute to subacute onset symptoms requiring hospitalization when severe. This article reviews the acute phase assessment and management of these disorders, with a particular focus on multiple sclerosis, neuromyelitis optica spectrum disorder, myelin oligodendrocyte glycoprotein antibody disorder, and several atypical demyelinating diseases.

Frequency and predictors of occult cancer in ischemic stroke: A systematic review and meta-analysis

BACKGROUND

The optimal approach for cancer screening after an ischemic stroke remains unclear.

AIMS

We sought to summarize the existing evidence regarding the frequency and predictors of cancer after an ischemic stroke.

SUMMARY OF REVIEW

We searched seven databases from January 1980 to September 2019 for articles reporting malignant tumors and myeloproliferative neoplasms diagnosed after an ischemic stroke (PROSPERO protocol: CRD42019132455). We screened 15,400 records and included 51 articles. The pooled cumulative incidence of cancer within one year after an ischemic stroke was 13.6 per thousand (95% confidence interval [CI], 5.6-24.8), higher in studies focusing on cryptogenic stroke (62.0 per thousand; 95% CI, 13.6-139.3 vs 9.6 per thousand; 95% CI, 4.0-17.3; p = 0.02) and those reporting cancer screening (39.2 per thousand; 95% CI, 16.4-70.6 vs 7.2 per thousand; 95% CI, 2.5-14.1; p = 0.003). Incidence of cancer after stroke was generally higher compared to people without stroke. Most cases were diagnosed within the first few months after stroke. Several predictors of cancer were identified, namely older age, smoking, and involvement of multiple vascular territories as well as elevated C-reactive protein and d-dimers.

CONCLUSIONS

The frequency of incident cancer after an ischemic stroke is low, but higher in cryptogenic stroke and after cancer screening. Several predictors may increase the yield of cancer screening after an ischemic stroke. The pooled incidence of post-stroke cancer is likely underestimated, and larger studies with systematic assessment of cancer after stroke are needed to produce more precise and valid estimates.

Learnings from 30 years of reported efficacy and safety of vagus nerve stimulation (VNS) for epilepsy treatment: A critical review

Three decades after its introduction as an adjuvant therapeutic option in the management of selective drug-resistant epilepsy cases (DRE), vagus nerve stimulation (VNS) retains growing interest. An implantable device was first approved for epilepsy in Europe in 1994 and in the United States (US) in 1997. Subsequent modifications improved the safety and the efficacy of the system. The most recent application of vagal neurostimulation is represented by transcutaneous devices that are claimed to have strong therapeutic potential. In this review, we sought to analyze the most meaningful available data describing the indications, safety and efficacy of the different approaches of VNS in clinical practice. Therefore, we identified studies reporting VNS efficacy and/or safety in epilepsy and its comorbidities from January 1990 to February 2020 from various databases including PubMed, Scopus, Cochrane, US government databases and VNS manufacturer published resources. In general, VNS efficacy becomes optimal around the sixth month of treatment and a 50-100 % seizure frequency reduction is achieved in approximately 45-65 % of the patients. However, some clinically relevant differences have been reported with specific factors such as epilepsy etiology or type, patient age as well as the delay of VNS therapy onset. VNS efficacy on seizure frequency has been demonstrated in both children and adults, in lesional and non-lesional cases, in focal and generalized epilepsies, on both seizures and epilepsy comorbidities. Regarding the latter, VNS can lead to an improvement of about 25-35 % in depression scores, 35 % in anxiety scores and 25 % in mood assessment scores. If non-invasive devices are undeniably safer, their efficacy is limited due to the scarcity of large cohort studies and the disparity of methodological approaches (study design and stimulation parameters). Overall, we believe that there is a progress margin for improving the safety of implantable devices and, above all, the effectiveness of the various VNS approaches.

Stent Retrievers for the Treatment of Acute Ischemic Stroke: A Systematic Review and Meta-analysis of Randomized Clinical Trials

IMPORTANCE

Stent retrievers are a promising alternative for the treatment of acute ischemic stroke (AIS). Several recently completed clinical trials have examined the use of stent retrievers with intravenous recombinant tissue plasminogen activator (rtPA) compared with rtPA alone.

OBJECTIVE

To conduct a systematic review and meta-analysis of randomized clinical trials to quantify the benefits and risks of using stent retrievers in addition to rtPA for the treatment of AIS.

DATA SOURCES

The MEDLINE, EMBASE, and Cochrane Library of Clinical Trials databases were searched from inception to July 2015 for the keywords stent*, retriev*, Solitaire, Trevo, Revive, and stroke. Trial registries were also searched. A total of 326 publications were identified and 213 potentially relevant records were screened.

STUDY SELECTION

Randomized clinical trials that examined stent retrievers with rtPA vs rtPA alone were included in the meta-analysis.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted study data and performed quality assessment using the Cochrane Risk of Bias Tool. DerSimonian and Laird random-effects models were used to estimate relative risks (RRs), risk differences (RDs), and numbers needed to treat.

MAIN OUTCOMES AND MEASURES

The primary outcome was the proportion of patients achieving functional independence (defined as a score of 0-2 on the modified Rankin Scale, with 0 indicating no disability and 6 indicating death) at 90 days. Risks of all-cause mortality, intracranial hemorrhage, and parenchymal hematoma at 90 days were also assessed.

RESULTS

Five randomized clinical trials met our inclusion criteria (n = 1287 patients). Patients randomized to stent-retriever therapy with rtPA had significantly improved rates of functional independence at 90 days compared with those randomized to rtPA alone (RR, 1.72; 95% CI, 1.48-1.99; RD, 0.19; 95% CI, 0.13-0.25). When data were pooled across trials, the effect of stent-retriever therapy on all-cause mortality at 90 days was inconclusive (RR, 0.82; 95% CI, 0.60-1.11; RD, -0.04; 95% CI, -0.08 to 0.1). There were similarly no detectable differences in the risks of intracranial hemorrhage (RR, 1.15; 95% CI, 0.67-1.97; RD, 0.00; 95% CI, -0.02 to 0.03) or parenchymal hematoma (RR, 1.18; 95% CI, 0.71-1.94; RD, 0.01; 95% CI, -0.01 to 0.04), although the 95% CIs were wide. Fixed-effects sensitivity analyses produced similar results for all outcomes.

CONCLUSIONS AND RELEVANCE

The use of stent retrievers in conjunction with rtPA vs rtPA alone is associated with significant improvement of functional independence 90 days after AIS.

Varenicline and Adverse Cardiovascular Events: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Varenicline is an efficacious smoking‐cessation drug. However, previous meta‐analyses provide conflicting results regarding its cardiovascular safety. The publication of several new randomized controlled trials (RCTs) provides an opportunity to reassess this potential adverse drug reaction.

Methods and Results

We searched MEDLINE, EMBASE, and the Cochrane Library for RCTs that compare varenicline with placebo for smoking cessation. RCTs reporting cardiovascular serious adverse events and/or all‐cause mortality during the treatment period or within 30 days of treatment discontinuation were eligible for inclusion. Relative risks (RRs) with 95% CIs were generated by using DerSimonian–Laird random‐effects models. Thirty‐eight RCTs met our inclusion criteria (N=12 706). Events were rare in both varenicline (57/7213) and placebo (43/5493) arms. No difference was observed for cardiovascular serious adverse events when comparing varenicline with placebo (RR 1.03, 95% CI 0.72–1.49). Similar findings were obtained when examining cardiovascular (RR 1.04, 95% CI 0.57–1.89) and noncardiovascular patients (RR 1.03, 95% CI 0.64–1.64). Deaths were rare in both varenicline (11/7213) and placebo (9/5493) arms. Although 95% CIs were wide, pooling of all‐cause mortality found no difference between groups (RR 0.88, 95% CI 0.50–1.52), including when stratified by participants with (RR 1.24, 95% CI 0.40–3.83) and without (RR 0.77, 95% CI 0.40–1.48) cardiovascular disease.

Conclusions

We found no evidence that varenicline increases the rate of cardiovascular serious adverse events. Results were similar among those with and without cardiovascular disease. Given varenicline's efficacy as a smoking cessation drug and the long‐term cardiovascular benefits of cessation, it should continue to be prescribed for smoking cessation.

Cathétérisme triple axial renforcé des tortuosités cervico-encéphaliques

Tortuous anatomy of the cervicoencephalic vessels can cause failure in 4 to 6% of interventional procedures by slippage of the material back in the aorta, kinking or difficulty to move forward a balloon. stent or microcatheter. We report on an old patient with high vascular tortuosity, referred for embolization of a ruptured aneurysm of the left inferior cerebellar artery. Access wasn't possible until we used a "triple axial system" with a long 7F sheath, positioned in the left subclavian artery and strongly supported by a super stiff guidewire with its distal end floating freely in the vascular lumen. Inside the sheath and parallel to the guidewire, we pushed a 4F catheter till the mid-vertebral artery. The microcatheter-microguide system tracked through it, towards the aneurysm, with the backward tendency being neutralized by the increased stiffness. Our technique presents the advantage of a strong back-up support, without increased risks such as vasospasm, clotting or dissection, since the guidewire serving as a stiff rail, lies exteriorly to the navigated vessel. Efficiency of this elegant and relatively low risk solution has yet to be proved in larger series.

Angioplastie avec mise en place d’un stent pour occlusion fessière

We report the case of a patient presenting severe buttock claudication with normal neurologic and osteoarticular exams. He underwent a guidewire recanalization of his occluded superior gluteal artery followed by a percutaneous angioplasty with stenting, resulting in total relief of symptoms. This observation represents the first publication describing the use of a stent with recanalization of the gluteal artery. The technique seems promising for buttock pathology.