Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

AB0382 COMPARISON OF ADVERSE EVENTS (AEs) RELATED TO MAJOR ANTI-RHEUMATIC DRUGS, REPORTED TO THE OFFICIAL JAPANESE ADVERSE DRUG EVENT REPORT DATABASE (JADER)

Background

Currently, many disease-modifying anti-rheumatic drugs (DMARDs) are available for the treatment of rheumatoid arthritis (RA). Among them, methotrexate (MTX), biologic DMARDs (bDMARDs) and Janus kinase inhibitors (JAKi) are the major options. AEs related to these are major concerns. In Japan, the AEs data spontaneously reported to and summarized by Pharmaceuticals and Medical Devices Agency (PMDA) are freely accessible.

Objectives

The major AEs relating to MTX, bDMARDs, and JAKi observed in the real world were compared.

Methods

The number of AEs listed by JADER from 2014 to 2020 was collected. The AEs were classified by System Organ Class (SOC) of Medical Dictionary for Regulatory Activities (MedDRA) and compared using the chi-square test. The bDMARDs included were etanercept (ETN), adalimumab (ADA), golimumab (GOL), tocilizumab (TCZ), and abatacept (ABT), and JAKi was tofacitinib (TOF) and baricitinib (BAR).

Results

The total number of AEs was 27,604. The number was significantly increasing in total and MTX, GOL, TOF during these years, although the number of cases that have each DMARD is not known in this study. The proportion of SOCs among each DMARD was similar throughout the period.

The most frequent was infections/infestations in all DMARDs except for MTX, in which neoplasms were the most. The primary cause of infection was bacterial, including pneumonia. Varicella-zoster virus infection in JAKi, and tuberculosis in ADA and GOL were conspicuous.

Neoplasms were the second major in many DMARDs. Lymphoproliferative disorders were most common in MTX-related neoplasms, whereas solid tumors were more in other DMARDs like ABT or BAR.

Other SOCs include all other categories such as the musculoskeletal, nervous system, cardiac, and vascular disorders. Among them, major adverse cardiovascular events (MACE, including cardiovascular death, myocardial infarction and stroke) and venous thromboembolism (VTE) were both reported in small numbers. However, more MACE was noted in BAR and GOL, and more VTE was in BAR and TOF compared to other DMARDs.

Conclusion

The number of AEs cases related to DMARDs was increasing. Significant difference among AEs related to DMARDs was noted in the JADER database, especially regarding MTX and JAKi.

References

[1]S. Inokuma. Expert Open Drug Saf. 2021 Nov 11. Online ahead of print.

Table 1.

Total case numbers and proportion of adverse events related to each DMARD.

DMARDs (year of launch)TotalMTX (1999)ETN (2005)ADA (2008)GOL (2011)TCZ (2008)ABT (2010)TOF (2013)BAR (2017)Number of AEs2760411636297419591302424517093065714Blood/lymphatic system disorders5.89.92.03.22.64.00.92.83.5Gastrointestinal disorders5.04.13.47.55.97.73.95.24.2General disorders/administration site reactions4.63.211.34.12.23.04.07.62.5Infections/infestations28.020.321.332.234.236.537.137.049.2 Pneumonia (bacterial)6.64.06.15.210.97.712.59.415.1 Other bacterial infection9.15.95.612.39.517.69.19.810.6 Herpes zoster2.11.10.41.41.21.01.28.211.2 Tuberculosis1.40.91.96.03.50.60.60.31.0Investigations5.04.95.52.32.65.72.28.32.8Neoplasms benign, malignant, unspecified21.134.811.013.512.77.415.610.815.4 Lymphoproliferative diseases14.329.82.84.14.02.24.52.12.2 Solid tumors5.63.87.37.87.54.09.97.310.5Respiratory, thoracic, mediastinal disorders7.16.88.38.49.56.57.46.26.7Other System Organ Class23.315.937.328.830.229.228.922.215.7 Major adverse cardiovascular events1.10.41.11.62.51.51.61.32.9 Venous thromboembolism0.40.10.40.50.60.30.21.11.4

Background colors indicate: comparing to the total cases, higher with p<0.05, light pink; higher with p<0.00001, dark pink; higher with p<1E-10, red. Lower with p<0.05, light blue; lower with p<0.00001, blue; lower with p<1E-10, dark blue, using chi-square test. Yellow indicates System Organ Classes.

Figure 1.

Total number of adverse events reported from 2014 to 2020.

Linear regression is shown only for DMARDs with increasing numbers of AEs.

Disclosure of Interests

None declared

Controlling joint instability after anterior cruciate ligament transection inhibits transforming growth factor-beta-mediated osteophyte formation

OBJECTIVE

Abnormal joint instability contributes to cartilage damage and osteophyte formation. We investigated whether controlling joint instability inhibited chronic synovial membrane inflammation and delayed osteophyte formation and examined the role of transforming growth factor-beta (TGF-β) signaling in the associated mechanism.

DESIGN

Rats (n = 94) underwent anterior cruciate ligament (ACL) transection. Anterior tibial instability was either controlled (CAM group) or allowed to continue (SHAM group). At 2, 4, and 8 weeks after surgery, radiologic, histopathologic, immunohistochemical, immunofluorescent, and enzyme-linked immunosorbent assay examinations were performed to evaluate osteophyte formation and TGF-β signaling.

RESULTS

Joint instability increased cartilage degeneration score and osteophyte formation, and cell hyperplasia and proliferation and synovial thickening were observed in the synovial membrane. Major findings were increased TGF-β expression and Smad2/3 following TGF-β phosphorylation in synovial membarene, articular cartilage, and the posterior tibial growth plate (TGF-β expression using ELISA: 4 weeks; P = 0.009, 95% CI [260.1-1340.0]) (p-Smad2/3 expression density: 4 weeks; P = 0.024, 95% CI [1.67-18.27], 8 weeks; P = 0.034, 95% CI [1.25-25.34]). However, bone morphogenetic protein (BMP)-2 and Smad1/5/8 levels were not difference between the SHAM model and the CAM model.

CONCLUSIONS

This study showed that the difference between anterior tibial instability caused a change in the expression level of TGF in the posterior tibia and synovial membrane, and the reaction might be consequently involved in osteophyte formation.

Chronic active Epstein-Barr virus infection mimicking autoimmune hepatitis exacerbation in a patient with systemic lupus erythematosus

Chronic active Epstein-Barr virus infection (CAEBV) is characterized by chronic infectious mononucleosis-like symptoms. We report a very rare case with autoimmune hepatitis (AIH) complicated by CAEBV. A 50-year-old woman with systemic lupus erythematosus (SLE) complicated by AIH began to suffer from acute respiratory failure and her clinical symptoms improved rapidly in response to steroid treatment. However, during the gradual tapering of the steroid dose, a steady increase of the serum hepatobiliary enzyme levels subsequently was observed and the patient began to have continuous fever. Moreover, upper gastrointestinal endoscopy revealed multiple intractable gastric ulcers. When EBER-ISH was performed on liver biopsy and gastric mucosal biopsy specimens, EBER-positive lymphocytes were observed. When peripheral blood was examined, 2.1 × 10(6) copies/µg of EBV-DNA were observed in the CD4-positive T cells, confirming the diagnosis of CAEBV. A cooling therapy was started by steroid and cyclosporine. Thereafter, despite the start of CHOP therapy, she developed a malignant lymphoma (PTCL-NOS) and died of hepatic failure. When treatment-resistant AIH patients are encountered, not only AIH exacerbation but also CAEBV should be considered in the differential diagnosis.

Dextromethorphan for neuropathic pain with Churg-Strauss syndrome

Abstract A 48-year old man who had been treated with prednisolone, aminophylline, and pranlukast, a leukotriene-receptor antagonist, was diagnosed with Churg-Strauss syndrome based on the findings of asthma, eosinophilia, mononeuropathy, and extravascular eosinophils. Intractable neuropathic pain of the legs was successfully controlled with an N-methyl-d-aspartate receptor antagonist, dextromethorphan. We suggest that dextromethorphan receptor antagonists may be a useful treatment for the pain of neuropathy caused by vasculitis syndrome.

Effect of surface treatments on the bond strengths of facing composite resins to zirconia copings

The present study evaluated and compared the bond strength between zirconia and facing composite resin using different surface conditioning methods before and after thermocycling. Four primers, three opaque resins, and two facing composite resins were used, and 10 surface treatment procedures were conducted. The bond strength was measured before and after 4,000 cycles of thermocycling. The mean values of each group were statistically analyzed using one-way analysis of variance (ANOVA). The bond strengths of facing composite resins to zirconia after various treatments varied depending on the primers, opaque resins, body resins, and thermocycling. The application of primers and opaque resins to the zirconia surface after sandblasting is expected to yield strong bond strength of the facing composite resin (Estenia CG&B) even after thermocycling.

Control of individual phase relationship between coupled oscillators using multilinear feedback

Due to various technological and medical demands, several methods for controlling the dynamical behavior of coupled oscillators have been developed. In the present study, we develop a method to control the individual phase relationship between coupled oscillators, in which multilinear feedback is used to modify the interaction between the oscillators. By carrying out a simulation, we show that the phase relationship can be well controlled by using the proposed method and the control is particularly robust when the target coupling function is selected properly.

Retention of zirconia copings on zirconia implant abutments cemented with provisional luting agents

The purpose of this study is to measure and compare the retentive force of zirconia-based all-ceramic crowns cemented on zirconia abutments using five provisional luting agents. In addition, the effect of sandblasting and thermocycling on the retentive force was evaluated. Two hundred zirconia abutments and copings were fabricated (Procera system; Nobel Biocare) and divided into five groups. Hy bond temporary cement hard (Hard), Hy bond temporary cement soft (Soft), experimental temporary cement (New), Tempbond NE (Temp) and Freegenool temporary pack (Pack) were used according to the manufacturers' instructions. Each group was divided into two groups, one with and one without sandblasting. Furthermore, thermocycling up to 2000 cycles was conducted on half of each group. After 24 h and thermocycling, the retentive force was measured using a universal testing machine. The data were subjected to analysis of variance, and comparisons of the means were performed with a Games-Howell test at a level of 95%. As a result, Hard showed the highest retentive force, sandblasting was effective for improving the durability, and no effect of sandblasting was detected in the others. New showed stability of the retentive force even after thermocycling. The retentive force of Temp and Pack decreased significantly after thermocycling even with sandblasting. The retentive forces were different from the provisional cement and sandblasting, and Temp and Pack may not be appropriate for the retention of single-tooth zirconia abutments and coping restorations.

Modeling of a density oscillator

A density oscillator is a well-known system, which exhibits relaxation oscillation. It alternately exhibits up and down flows through a pipe that connects two containers filled with fluids that have different densities. Although the up-flow, down-flow, and flow-reversal processes have been studied separately, the entire oscillatory dynamics has not been modeled quantitatively. In this study, we derive a model of a density oscillator by considering all the above mentioned processes. The model thus obtained describes the oscillatory behavior in a unified manner, and its viscosity and pipe-length dependence is well described. Moreover, for the demonstration of this model, we have extended it to describe the dynamical behaviors observed in coupled density oscillators. Thus, this model provides a general expression for density oscillators.

Method to control the coupling function using multilinear feedback

Methods to control the dynamics of coupled oscillators have been developed owing to various medical and technological demands. In this study, we develop a method to control coupled oscillators in which the coupling function expressed in a phase model is regulated by the multilinear feedback. The present method has wide applicability because we do not need to measure an individual output from each oscillator, but only measure the sum of the outputs from all the oscillators. Moreover, it allows us to easily control the coupling function up to higher harmonics. The validity of the present method is confirmed through a simulation.

Evaluation of plasma C-terminal atrial natriuretic peptide in healthy cats and cats with heart disease

BACKGROUND

The clinical implications of evaluating C-terminal atrial natriuretic peptide (ANP) concentration in cats are still controversial.

HYPOTHESIS

The objective of this study was to investigate the relationship between plasma C-terminal ANP concentration and left atrial pressure (LAP) in healthy cats with volume overload (study 1), and to compare plasma C-terminal ANP in normal cats and cats with cardiomyopathy (study 2).

ANIMALS

Five healthy adult cats were used in study 1, and clinically healthy cats (n=8) and cats with cardiomyopathy (n=14) were used in study 2.

METHODS

In study 1, cats were anesthetized and given acetated Ringer's solution (100 mL/kg/h for 60 minute) via the cephalic vein. Hemodynamic measurements and blood samples, collected from the jugular vein, were performed at 10-min intervals. In study 2, blood samples from normal cats and cats with cardiomyopathy were collected from the cephalic vein. The plasma C-terminal ANP concentration was determined by radioimmunoassay for human alpha-ANP.

RESULTS

In study 1, volume overload significantly increased the C-terminal ANP concentration and LAP from baseline. The C-terminal ANP concentration was strongly correlated with the mean LAP. In study 2, age, E wave velocity, and the ratios of the left atrium to aorta were significantly higher in the cats with cardiomyopathy compared with the normal cats. The C-terminal ANP concentration was significantly higher in the cats with cardiomyopathy compared with the normal cats.

CONCLUSIONS AND CLINICAL IMPORTANCE

Our results suggest that the measurement of plasma C-terminal ANP in cats may provide additional information for the diagnosis of heart disease.

Optical topography can predict occurrence of watershed infarction during carotid endarterectomy: technical case report

BACKGROUND

The major risk of CEA is perioperative stroke. NIRS can detect ischemic changes during CEA; however, possible watershed-type perfusion defects may not be detected by single-channel NIRS occurring at some distance from the light source. In the present case, we tested the usefulness of optical topography (ie, multichannel NIRS, OT) for this purpose.

CASE DESCRIPTION

The patient (64-year-old man) exhibited nonsymptomatic 80% stenosis of the right ICA with normal cerebral perfusion. CEA was performed to prevent cerebral infarction. We used single-channel NIRS and OT for monitoring of perfusion changes during CEA. The optodes of OT were placed on the skull to cover the frontal and parietal lobes on the right side, whereas the sensor of the single-channel NIRS was placed on the right forehead. The single-channel NIRS detected no significant perfusion changes during surgery. However, the OT revealed occurrence of watershed-type perfusion defects in the border region between the right middle and posterior cerebral artery supply areas during cross-clamping of the right internal carotid artery. Postoperative MRI showed an ischemic region which corresponded to the area associated with the perfusion defects.

CONCLUSION

OT could detect watershed-type posterior perfusion defects which the single-channel NIRS failed to detect. OT may represent a useful tool for intraoperative monitoring during CEA.

Intravenous infusion of calcium antagonist, nicardipine, does not increase intracranial pressure: evaluation in a rat model of transient cerebral ischemia and reperfusion

OBJECTIVE AND METHOD

Early use of parenteral antihypertensive drugs is recommended in acute ischemic stroke patients suffering hypertensive emergencies. Calcium antagonist has been widely employed, although there is controversy as to whether calcium antagonist can be administered safely to patients with intracranial hypertension. In a rat model of transient cerebral ischemia and reperfusion, we evaluated the effect of the calcium antagonist, nicardipine, on intracranial pressure (ICP). Using spontaneously hypertensive rats (SHRs), focal cerebral ischemia was induced by an intraluminal thread method. ICP was monitored continuously employing an intraparenchymal catheter. The mean arterial blood pressure (MABP) was reduced by infusing nicardipine intravenously.

RESULTS

Following 6 hours of transient ischemia and reperfusion, MABP was decreased by about 10 or 20% as compared to the baseline MABP with low-dose or high-dose nicardipine administration, respectively. ICP was significantly increased following reperfusion, although it did not increase further with nicardipine infusion.

CONCLUSION

Under conditions where ICP was high following reperfusion, nicardipine reduced blood pressure safely without increasing ICP in rats.

Comparison of blood-oxygen-level-dependent functional magnetic resonance imaging and near-infrared spectroscopy recording during functional brain activation in patients with stroke and brain tumors

Blood-oxygen-level-dependent contrast functional magnetic resonance imaging (BOLD-fMRI) has been used to perform functional imaging in brain disorders such as stroke and brain tumors. However, recent studies have revealed that BOLD-fMRI does not image activation areas correctly in such patients. To clarify the characteristics of the evoked cerebral blood oxygenation (CBO) changes occurring in stroke and brain tumors, we have been comparing near-infrared spectroscopy (NIRS) and BOLD-fMRI recording during functional brain activation in these patients. We review our recent studies and related functional imaging studies on the brain disorders. In the primary sensorimotor cortex (PSMC) on the nonlesion side, the motor task consistently caused a decrease of deoxyhemoglobin (deoxy-Hb) with increases of oxyhemoglobin (oxy-Hb) and total hemoglobin (t-Hb), which is consistent with the evoked CBO response observed in normal adults. BOLD-fMRI demonstrated robust activation areas on the nonlesion side. In stroke patients, severe cerebral ischemia (i.e., misery perfusion) caused an increase of deoxy-Hb during the task, associated with increases of oxy-Hb and t-Hb, in the PSMC on the lesion side. In addition, the activation volume of BOLD-fMRI was significantly reduced on the lesion side. The BOLD signal did not change in some areas of the PSMC on the lesion side, but it tended to decrease in other areas during the tasks. In brain tumors, BOLD-fMRI clearly demonstrated activation areas in the PSMC on the lesion side in patients who displayed a normal evoked CBO response. However, the activation volume on the lesion side was significantly reduced in patients who exhibited an increase of deoxy-Hb during the task. In both stroke and brain tumors, false-negative activations (i.e., marked reductions of activation volumes) in BOLD imaging were associated with increases of deoxy-Hb, which could cause a reduction in BOLD signal. BOLD-fMRI investigations of patients with brain disorders should be performed while giving consideration to atypical evoked CBO changes.

Viscosity-dependent flow reversal in a density oscillator

The density oscillator is a simple system that exhibits self-sustained oscillation. It alternately exhibits up and down flow through a pipe which connects two containers filled with fluids of different densities. However, the mechanism of the flow reversal has not yet been fully understood. From the detailed measurements, we have found that flow reversal begins with an intrusion of fluid, which is followed by rapid growth. This process is definitely sensitive to the viscosities of the fluids, and as a consequence, the critical heights leading to flow reversal are clearly viscosity dependent. These experimental results are explained by a simple model, derived by considering forces acting on a unit volume element located at the tip of the intrusion. Using this model, we can successfully explain the mechanism of flow reversal, which is the most essential process in a density oscillator.

Combination Therapy Using tPA and Edaravone Improves the Neurotoxic Effect of tPA

SUMMARY

In acute ischemic stroke patients, administration of tissue plasminogen activator (tPA) was proven to improve clinical outcome. On the other hand, neurotoxic effects of tPA have been reported in animal experimental studies. Using a rat thromboembolic stroke model, we examined whether or not the free radical scavenger, edaravone, could attenuate such neurotoxic effect of tPA administered for the purpose of fibrinolysis. Even when early recanalization was induced by administering tPA at 30 minutes after the onset of ischemia, significant amount of tPA was extravasated through the cerebral vessels. Edaravone significantly attenuated extravasation of tPA. Combination therapy using tPA and edaravone appears to be a promising strategy for diminishing the negative effects of tPA.

Effects of Cerebral Ischemia on Evoked Cerebral Blood Oxygenation Responses and BOLD Contrast Functional MRI in Stroke Patients

Background and Purpose— To evaluate the mechanisms of failure of blood oxygenation level–dependent (BOLD) imaging in stroke, we compared the evoked cerebral blood oxygenation (CBO) responses and activation volumes (AVs) of BOLD functional MRI (fMRI) in chronic stroke patients with moderate and severe cerebral ischemia.

Methods— We measured the evoked CBO responses in the primary sensorimotor cortex (PSMC) by means of near-infrared spectroscopy during contralateral motor tasks. We compared the AV of BOLD-functional MRI in the PSMC on the nonlesion and lesion sides. Single-photon emission computed tomography was used to classify ischemic status as moderate (slight reduction of regional cerebral blood flow and cerebrovascular reserve capacity [CVRC]) or severe (marked reduction of regional cerebral blood flow and CVRC; ie, misery perfusion).

Results— In age-matched controls, deoxyhemoglobin concentration decreased with concomitant increases in oxyhemoglobin and total hemoglobin concentrations during activation. The PSMC on the nonlesion side exhibited a normal CBO response pattern. On the lesion side, moderate cerebral ischemia did not affect the CBO response pattern, but severe cerebral ischemia caused an increase of deoxyhemoglobin during the task, associated with increases of oxyhemoglobin and total hemoglobin. Moderate cerebral ischemia induced only a slight reduction of the AV on the lesion side; however, severe cerebral ischemia markedly reduced the AV on the lesion side. The BOLD signal did not change in some areas of the PSMC on the lesion side in severe cerebral ischemia, whereas it tended to decrease in other areas during the tasks.

Conclusions— Misery perfusion caused a marked reduction of the AV on BOLD imaging, associated with an increase of deoxyhemoglobin concentration during activation. BOLD-fMRI investigations of stroke patients should be performed while giving consideration to baseline circulatory status. Functional near-infrared spectroscopy could be an alternative means to assess the CVRC.

[A case of cerebral arteriovenous malformation revealing repeated intranidal hemorrhage accompanying neovascularization after stereotactic radiosurgery]

We report a patient with cerebral arteriovenous malformation (AVM) revealing growing mass lesion after stereotactic radiosurgery. This 12-year-old female presented headache. CT scan showed hematoma at the head of the right caudate nucleus and angiography showed AVM at the site. LINAC-based stereotactic radiosurgery was performed with the patient. Twenty-three months after the radiosurgery the patient complained headache and CT scan showed hematoma again at the same site, although angiography did not show AVM. Thirty-five months after the radiosurgery mass lesion with enhancement effect was observed at the site and the mass lesion grew gradually thereafter. Thirty-nine months after the radiosurgery the mass lesion was evacuated. Histological examination revealed fibrotic core and surrounding neovascularized area with hemorrhage. The histology shows a new etiology of growing mass lesion after radiosurgery for AVM.

Intraoperative monitoring of cerebral blood oxygenation and hemodynamics during extracranial-intracranial bypass surgery by a newly developed visible light spectroscopy system

BACKGROUND

Cerebrovascular reconstruction procedures run the risk of changing the balance between oxygen supply and consumption during surgery. We assessed the value of visual light spectroscopy for detecting changes in cerebral blood oxygenation (CBO) during superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis.

METHODS

We developed a VLS monitoring system which permits continuous monitoring of CBO changes during surgery. Using the VLS, we evaluated the CBO changes in the MCA territory on the lesion side in 18 patients who underwent STA-MCA anastomosis.

RESULTS

Temporary occlusion of the MCA (M4 portion) did not change the CBO in 17 patients. However, in the patient with dissecting aneurysm, it caused decreases of oxyhemoglobin and cortical oxygen saturation (CoSo(2)) associated with an increase of deoxyhemoglobin, although these CBO changes were normalized by STA blood flow. In 5 patients, STA blood flow increased the oxyhemoglobin and CoSo(2) and decreased the deoxyhemoglobin, indicating that cortical blood flow (CoBF) was increased. The CoSo(2) before anastomosis was significantly low in the patients who showed an increase of CoSo(2) by STA blood flow (63.0% +/- 2.5%) as compared with those who did not (72.0 +/- 6.1%, P = .024).

CONCLUSION

Temporary occlusion of a cortical artery during bypass surgery did not affect the CBO in patients who had chronic cerebral ischemia, but caused acute ischemia in the patient who did not. STA blood flow increased the CoBF during surgery more frequently in patients who showed a low perfusion pressure. The VLS monitoring system is considered useful for evaluating bypass function and facilitates safe and accurate bypass surgery.

Cerebral blood oxygenation changes induced by bypass blood flow in moyamoya disease and non-moyamoya cerebral ischaemic disease

BACKGROUND

Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis has been used to prevent stroke in patients with moyamoya disease (MD) and non-moyamoya ischaemic disease (non-MD). However, little is yet known regarding the difference between these groups of patients in the extent to which the bypass contributes to maintaining adequate cerebral blood oxygenation (CBO), or the temporal changes after surgery. In the present study, we evaluated the CBO changes induced by bypass blood flow in patients with MD and non-MD during the peri-operative periods employing optical spectroscopy.

METHODS

We investigated 13 patients who underwent STA-MCA anastomosis, including 5 MD and 8 non-MD patients. We evaluated the effects of STA blood flow on the CBO in the MCA territory on the anastomosis side, employing visual light spectroscopy during surgery and near infrared spectroscopy (NIRS) at one week after surgery.

FINDINGS

In 4 MD patients and one non-MD patient, the STA blood flow increased the oxyhaemoglobin and cortical oxygen saturation (CoSO2), indicating that the bypass supplied blood flow to the ischaemic brain; the CBO changes were observed more frequently in MD than in non-MD patients (p<0.02). The pre-anastomosis CoSO2 (65.4+/-5.4%) in MD was significantly lower than that (72.8+/-7.6%) in non-MD (p<0.05). Postoperative NIRS demonstrated that the bypass began to supply blood flow to the brain in 5 non-MD patients whose bypass did not supply blood flow during surgery.

CONCLUSIONS

Although MD has vessels of small diameter as compared to non-MD, the bypass begins to supply blood flow to the ischaemic brain earlier in MD than in non-MD after anastomosis. The fact that the CoSO2 in MD was lower than that in non-MD suggested that the perfusion pressure in MD was lower than that in non-MD, and this might account for the difference in the bypass blood supply after anastomosis between MD and non-MD. Our data suggest that, even if the bypass does not supply blood to the brain during surgery in non-MD, the bypass blood flow gradually increases after surgery.

Pallidal high-frequency deep brain stimulation for camptocormia: an experience of three cases

INTRODUCTION

The term "camptocormia" describes a forward-flexed posture. It is a condition characterized by severe frontal flexion of the trunk. Recently, camptocormia has been regarded as a form of abdominal segmental dystonia. Deep brain stimulation (DBS) is a promising therapeutic approach to various types of movement disorders. The authors report the neurological effects of DBS to the bilateral globus pallidum (GPi) in three cases of disabling camptocormia.

METHODS

Of the 36 patients with dystonia, three had symptoms similar to that of camptocormia, and all of these patients underwent GPi-DBS. The site of DBS electrode placement was verified by magnetic resonance imaging (MRI). The Burke Fahn and Marsden dystonia rating scale (BFMDRS) was employed to evaluate the severity of dystonic symptoms preoperatively and postoperatively.

RESULTS

Significant functional improvement following GPi-DBS was noted in the majority of dystonia cases. At a follow-up observation after more than six months, the overall improvement rate was 71.2 +/- 27.0%, in all dystonia cases who underwent the GPi-DBS. In contrast, the improvement rate of the three camptocormia cases was 92.2 +/- 5.3%. It was confirmed that the improvement rate for camptocormia was much higher than for other types of dystonia.

CONCLUSION

According to our experience, a patient with a forward-bent dystonic posture indicative of camptocormia is a good candidate for GPi-DBS. The findings of this study add further support to GPi-DBS as an effective treatment for dystonia, and provide the information on predictors of a good outcome.

Detection of boundaries of subthalamic nucleus by multiple-cell spike density analysis in deep brain stimulation for Parkinson's disease

When microelectrode recording of single cell activity is employed for targeting the subthalamic nucleus (STN), multiple sampling of single cells is needed to determine whether the electrode has passed through the ventral boundaries of the STN. In contrast, stepwise recording of multiple cell activities by a semimicroelectrode reveals robust changes in such activities at the dorsal and ventral boundaries. We attempted to quantify changes in multiple cell activities by computing multiple-cell spike density (MSD). We analyzed MSD in 60 sides of 30 patients with Parkinson's disease. Neural noise level was defined as the lowest cut-off level at which neural noise is separated from larger amplitude spikes. MSD was analyzed at cut-off levels ranging from 1.2 to 2.0-fold the neural noise level in the white matter in each trajectory. Both the dorsal and ventral boundaries were clearly identified by an increase and a decrease (p < 0.0001) in MSD, respectively, in all the 60 sides. The cut-off level of 1.2-fold showed the clearest change in MSD between the STN and the pars reticulata of substantia nigra. MSD analysis by semimicroelectrode recording represents the most practical means of identifying the boundaries of STN.

Feed-forward control of post-stroke movement disorders by on-demand type stimulation of the thalamus and motor cortex

Deep brain stimulation (DBS) of the thalamus (Vo/Vim) has become popular as a means of controlling involuntary movements, including post-stroke movement disorders. We have also found that post-stroke movement disorders and motor weakness can sometimes be controlled by motor cortex stimulation (MCS). In some forms of movement disorders, motor dysfunction becomes evident only when patients intend to move their body. We have developed an on-demand type stimulation system which triggers stimulation by detecting intrinsic signals of intention to move. Such a system represents feed-forward control (FFC) of involuntary movements. We report here our experience of DBS and MCS for controlling post-stroke movement disorders, and discuss the value of FFC. Excellent control of post-stroke movement disorders was achieved by conventional DBS and/or MCS in 20 of 28 patients with hemichoreoathetosis, hemiballism tremor, and motor weakness. FFC was tested in 6 patients who demonstrated excellent control of post-stroke postural tremor or motor weakness by conventional DBS or MCS. The on-demand stimulation provided satisfactory FFC in 4 of 4 patients with postural tremor and 2 of 2 patients with motor weakness, when the activity of muscles involved in posturing or intention to move was fed into the system. These findings justify further clinical studies on DBS and MCS in patients with post-stroke movement disorders. The on-demand type stimulation system may also be useful for overcoming various post-stroke movement disorders.

Tissue plasminogen activator extravasated through the cerebral vessels: evaluation using a rat thromboembolic stroke model

Neurotoxic effects of endogenous tissue plasminogen activator (tPA) have recently been reported. Employing a rat model of thromboembolic stroke, we evaluated the extent and degree of extravasation of exogenous tPA administered for the purpose of fibrinolysis. In a thromboembolic model using Sprague-Dawley rats, focal cerebral ischemia was induced at the territory of the middle cerebral artery (MCA). Early reperfusion was induced by administering tPA (10 mg/kg) intravenously at 30 minutes after the onset of ischemia. Extravasated tPA was evaluated by immunohistochemistry, and the concentration of tPA in the brain tissue was quantified by enzyme-linked immunosorbent assay methods. The integrity of the blood-brain barrier (BBB) was examined electronmicroscopically. In a thread model of transient ischemia, reperfusion was induced without tPA administration at 30 minutes or 2 hours after the onset of ischemia, and the tPA content of the brain was quantified. In the rats with thromboembolic stroke, extravasation of tPA was observed at the territory of the MCA. Both the endogenous and exogenous tPA contents were 3.5 +/- 1.6 ng/ml of homogenized brain in saline. Electronmicroscopically, mild ischemic changes were observed, although the integrity of the BBB was preserved. In the thread model rats, the endogenous tPA contents of the ischemic hemisphere were 0.9 +/- 0.1 and 1.0 +/- 0.2 ng/ml in the 30-minute and 2-hour ischemia groups, respectively, and were significantly lower than the tPA contents in the thromboembolic stroke rats (p<0.01). The present findings indicate that significant extravasation of exogenous tPA occurs through the cerebral vessels even though early reperfusion is induced.

Attenuation of extravasation of tissue plasminogen activator by the free radical scavenger, edaravone: evaluation in a rat thromboembolic stroke model

OBJECTIVES AND METHODS

Deleterious effects of tissue plasminogen activator (tPA) have been described recently in experimental studies. For example, tPA can aggravate ischemic neuronal damage through its proteolytic activity. The present study was undertaken to examine whether or not the free radical scavenger, edaravone, could prevent the extravasation of tPA administered for the purpose of fibrinolysis in a rat model of thromboembolic stroke.

RESULTS

Significant amounts of tPA were extravasated through the cerebral vessels even when early recanalization was induced by administering tPA at 30 minutes after the onset of schema. Edaravone significantly attenuated such extravasation of tPA.

CONCLUSION

In acute ischemic stroke patients, combination therapy using tPA with edaravone appears to be a reasonable strategy for diminishing the negative effects of tPA.

A retrospective study of the fluctuation in serum levels of anti-cyclic citrullinated peptide antibody in patients with rheumatoid arthritis

OBJECTIVE

To investigate the fluctuation in serum levels of anti-cyclic citrullinated peptide antibody (anti-CCP) retrospectively in patients with rheumatoid arthritis (RA).

METHODS

Serum levels of anti-CCP were measured retrospectively in 131 patients with RA and 90 patients with non-RA rheumatic diseases using a commercially available kit. All sera were collected from patients during the 22-year period, 1982-2004. To analyze the fluctuation in anti-CCP levels, 17 RA patients were selected on the basis of showing a significantly higher anti-CCP level in a serum sample taken at the first visit (> 80 U/ml), and availability of preserved serum samples that had been taken from each patient at 10 time points.

RESULTS

The test gave a sensitivity of 88% (115/131) and a specificity of 81% (73/90). The longitudinal study of 17 RA patients showed that anti-CCP levels were elevated at the first visit in 12 (71%) patients and then decreased gradually, whereas those in the other five (29%) patients fluctuated substantially. In both cases, anti-CCP levels tended to fluctuate in parallel with the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level, reflecting the spontaneous aggravation of arthritis and the efficacy of anti-rheumatic drugs. The courses of three representative RA patients are illustrated in detail along with their therapeutic regimens, and these further confirm the correlation of anti-CCP levels with laboratory parameters (ESR and CRP) as well as the activity of arthritis.

CONCLUSION

Measurement of serum anti-CCP levels was found to be useful for not only the diagnosis but also the management of RA.