Eslicarbazepine acetate add-on therapy for drug-resistant focal epilepsy

BACKGROUND

This is an update of a review first published in 2011, and last updated in 2017. Most people with epilepsy have a good prognosis, but up to 30% of people continue to have seizures despite several regimens of antiepileptic drugs. In this review, we summarized the current evidence regarding eslicarbazepine acetate (ESL) when used as an add-on treatment for drug-resistant focal epilepsy.

OBJECTIVES

To evaluate the efficacy and tolerability of ESL when used as an add-on treatment for people with drug-resistant focal epilepsy.

SEARCH METHODS

For this update, we searched the following databases on 10 September 2020: Cochrane Register of Studies (CRS Web) and MEDLINE (Ovid). CRS Web includes randomized or quasi-randomized, controlled trials from Specialized Registers of Cochrane Review Groups including Epilepsy, CENTRAL, PubMed, Embase, ClinicalTrials.gov and the WHO ICTRP. There were no language restrictions. We reviewed the reference lists of retrieved studies and contacted the manufacturers of ESL and experts in the field for information about any unpublished or ongoing studies.

SELECTION CRITERIA

Randomized placebo-controlled double-blind add-on trials of ESL in people with drug-resistant focal epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and extracted data. Outcomes investigated included 50% or greater reduction in seizure frequency, seizure freedom, treatment withdrawal, adverse effects and drug interactions. Primary analyses were by intention to treat (ITT). The dose-response relationship was evaluated in regression models.

MAIN RESULTS

We included seven trials (2185 participants, aged 2 to 77 years), which were at low or unclear risk of bias apart from a high risk of attrition bias; all studies were funded by the pharmaceutical company, BIAL. The overall risk ratio (RR) for 50% or greater reduction in seizure frequency was 1.57 (95% confidence interval (CI) 1.34 to 1.83). For adults, the RR was 1.71 (95% CI 1.42 to 2.05; 5 studies, 1799 participants; moderate-certainty evidence); for children aged six to 18 years, the RR was 1.35 (95% CI 0.98 to 1.87; 2 studies, 322 participants; moderate-certainty evidence). Dose regression analysis showed evidence that ESL reduced seizure frequency with an increase in efficacy with increasing doses of ESL. ESL was associated with seizure freedom (RR 3.16, 95% CI 1.73 to 5.78; 6 studies, 1922 participants; moderate-certainty evidence). Participants were more likely to have ESL withdrawn for adverse effects (RR 2.72, 95% CI 1.66 to 4.46; 7 studies, 2185 participants; moderate-certainty evidence), but not for any reason (RR 1.25, 95% CI 0.93 to 1.70; 7 studies, 2185 participants; moderate-certainty evidence). The following adverse effects were associated with ESL: dizziness (RR 2.77, 99% CI 1.85 to 4.15); nausea (RR 2.55, 99% CI 1.39 to 4.67); somnolence (RR 1.75, 99% CI 1.18 to 2.61); diplopia (RR 4.07, 99% CI 1.86 to 8.89); and vomiting (RR 2.37, 99% CI 1.19 to 4.74). Overall, the certainty of the evidence was moderate due to a high discontinuation rate in studies of adults.

AUTHORS' CONCLUSIONS

ESL reduces seizure frequency when used as an add-on treatment for adults with drug-resistant focal epilepsy. The trials included in this review were of short-term duration. In addition, this update found that ESL may reduce seizure frequency in children from 6 to 18 years of age; however the results are inconclusive.

The adenosine A2A receptor antagonist SCH58261 reduces macrophage/microglia activation and protects against experimental autoimmune encephalomyelitis in mice

Multiple sclerosis (MS) is a chronic autoimmune inflammatory disease of the central nervous system (CNS) affecting more than 2.5 million individuals worldwide. In the present study, myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) mice were treated with adenosine receptor A_2A antagonist SCH58261 at different periods of EAE development. The administration of SCH58261 at 11-28 days post-immunization (d.p.i.) with MOG improved the neurological deficits. This time window corresponds to the therapeutic time window for MS treatment. SCH58261 significantly reduced the CNS neuroinflammation including reduced local infiltration of inflammatory cells, demyelination, and the numbers of macrophage/microglia in the spinal cord. Importantly, SCH58261 ameliorated the EAE-induced neurobehavioral deficits. By contrast, the SCH58261 treatment was ineffective when administered at the beginning of the onset of EAE (i.e., 1-10 d.p.i). The identification of the effective therapeutic window of A_2A receptor antagonist provide insight into the role of A_2A receptor signaling in EAE, and support SCH58261 as a candidate for the treatment of MS in human.

Reliability and validity of the Chinese version of the Patient Health Questionnaire 9 (C-PHQ-9) in patients with epilepsy

OBJECTIVE

The aim of this study was to evaluate the clinical reliability and validity of the Chinese version of the Patient Health Questionnaire 9 (C-PHQ-9) in patients with epilepsy.

METHODS

A total of 213 consecutive adult patients with epilepsy were evaluated. Receiver operating characteristic (ROC) analysis was performed using C-PHQ-9 and Chinese version of Patient Health Questionnaire 2 (C-PHQ-2) as predictors and the Mini International Neuropsychiatric Interview Plus Version 5.0.0 as the gold standard.

RESULTS

The C-PHQ-9 was easily understood and quickly finished by the patients. According to the gold standard, the prevalence of current major depressive disorder in this population was 16.4%. Cronbach's α coefficient for the C-PHQ-9 was 0.860. The ROC analysis showed an area under the curve (AUC) of 0.888 (95% confidence interval [CI] = 0.838-0.927). At a cutoff score of >6, the C-PHQ-9 had a sensitivity of 82.86%, a specificity of 84.27%, a positive predictive value of 50.9%, and a negative predictive value of 96.2%. The C-PHQ-2 at a cutoff score of >1 resulted in the greatest balance of sensitivity and specificity (77.14% and 75.28%, respectively).

CONCLUSION

Our findings support a high reliability and validity for the C-PHQ-9 as a screening tool for the detection of current major depression in Chinese patients with epilepsy.

Analysis of risk factors for antiepileptic drug-induced adverse psychotropic effects in Chinese outpatients with epilepsy

Antiepileptic drugs (AEDs) have adverse psychotropic effects (APEs). To explore the risk factors for AED-induced APEs, we compared Chinese outpatients with epilepsy with and without AED-induced APEs. We reviewed the medical data of outpatients with epilepsy enrolled in the Epilepsy Long-term Follow Up Registry Study (ELFURS) between January 1, 2003 and December 31, 2015. Data on demographics, comorbidities, variables related to epilepsy, AED use, and APEs were collected. APEs were determined by experienced epileptologists based on the definition of "adverse drug reaction (ADR)" proposed by the World Health Organization (WHO) in 1972, and the causality relationship between APEs and suspected medications was assessed based on the WHO-UMC scale. APEs included effects on memory, sleep, behavior, mood, psychotic symptoms, and others in this study. We divided the study population into patients with and without AED-induced APEs and then compared the differences between the two groups using univariate and multivariate methods. A total of 3074 eligible patients were included in this study (1001 patients with AED-induced APEs and 2073 patients without AED-induced APEs). Of all APEs, the effects on memory and sleep were most pronounced. The results show that the female sex (odds ratio [OR] 1.242, 95% confidence interval [CI] 1.055-1.463), psychotic disorder comorbidities (OR 1.815, 95% CI 1.159-2.841), polytherapy with AEDs (OR 1.400, 95% CI 1.061-1.847), and the duration of epilepsy (OR 1.010, 95% CI 1.000-1.020) are significant nondrug risk factors for AED-induced APEs. Recognizing risk factors for APEs may help determine optimal treatment strategies for epilepsy.

Comparative Long-Term Effectiveness of a Monotherapy with Five Antiepileptic Drugs for Focal Epilepsy in Adult Patients: A Prospective Cohort Study

Objective

To evaluate and compare long-term effectiveness of five antiepileptic drugs (AEDs) for monotherapy of adult patients with focal epilepsy in routine clinical practice.

Methods

Adult patients with focal epilepsy, who were prescribed with carbamazepine (CBZ), valproate (VPA), lamotrigine (LTG), topiramate (TPM), or oxcarbazepine (OXC) as monotherapy, during the period from January 2004 to June 2012 registered in Wenzhou Epilepsy Follow Up Registry Database (WEFURD), were included in the study. Prospective long-term follow-up was conducted until June 2013. The endpoints were time to treatment failure, time to seizure remission, and time to first seizure.

Results

This study included 654 patients: CBZ (n=125), VPA (n=151), LTG (n=135), TPM (n=76), and OXC (n=167). The retention rates of CBZ, VPA, LTG, TPM, and OXC at the third year were 36.1%, 32.4%, 57.6%, 37.9%, and 41.8%, respectively. For time to treatment failure, LTG was significantly better than CBZ and VPA (LTG vs. CBZ, hazard ratio, [HR] 0.80 [95% confidence interval: 0.67-0.96], LTG vs. VPA, 0.53 [0.37-0.74]); TPM was worse than LTG (TPM vs. LTG, 1.77 [1.15-2.74]), and OXC was better than VPA (0.86 [0.78-0.96]). After initial target doses, the seizure remission rates of CBZ, VPA, LTG, TPM, and OXC were 63.0%, 77.0%, 83.6%, 67.9%, and 75.3%, respectively. LTG was significantly better than CBZ (1.44 [1.15-1.82]) and OXC (LTG vs. OXC, 0.76 [0.63-0.93]); OXC was less effective than LTG in preventing the first seizure (1.20 [1.02-1.40]).

Conclusion

LTG was the best, OXC was better than VPA only, while VPA was the worst. The others were equivalent for comparisons between five AEDs regarding the long-term treatment outcomes of monotherapy for adult patients with focal epilepsy in a clinical practice. For selecting AEDs for these patients among the first-line drugs, LTG is an appropriate first choice; others are reservation in the first-line but VPA is not.

Fast, non-competitive and reversible inhibition of NMDA-activated currents by 2-BFI confers neuroprotection

Excessive activation of the N-methyl-D-aspartic acid (NMDA) type glutamate receptors (NMDARs) causes excitotoxicity, a process important in stroke-induced neuronal death. Drugs that inhibit NMDA receptor-mediated [Ca(2+)]i influx are potential leads for development to treat excitotoxicity-induced brain damage. Our previous studies showed that 2-(2-benzofu-ranyl)-2-imidazoline (2-BFI), an immidazoline receptor ligand, dose-dependently protects rodent brains from cerebral ischemia injury. However, the molecular mechanisms remain unclear. In this study, we found that 2-BFI transiently and reversibly inhibits NMDA, but not AMPA currents, in a dose-dependent manner in cultured rat cortical neurons. The mechanism of 2-BFI inhibition of NMDAR is through a noncompetitive fashion with a faster on (Kon = 2.19±0.33×10(-9) M(-1) sec(-1)) and off rate (Koff = 0.67±0.02 sec(-1)) than those of memantine, a gold standard for therapeutic inhibition NMDAR-induced excitotoxicity. 2-BFI also transiently and reversibly blocked NMDA receptor-mediated calcium entry to cultured neurons and provided long-term neuroprotection against NMDA toxicity in vitro. Collectively, these studies demonstrated a potential mechanism of 2-BFI-mediated neuroprotection and indicated that 2-BFI is an excellent candidate for repositioning as a drug for stroke treatment.

Neurovascular protection conferred by 2-BFI treatment during rat cerebral ischemia

Stroke is caused by vascular dysfunction and currently there are no effective therapeutics to stroke induced brain damage. In contrast to an intense emphasis on neuroprotection, relatively few studies have addressed means of vascular protection in cerebral ischemia. Here we discovered that the ligand to immidazolin receptor, 2-BFI, not only provided potent neuroprotection during middle cerebral artery occlusion in rat, which confirmed our previous reports, but also protected the integrity of the cerebral vasculature. Treatment with 2-BFI twice daily after the occlusion of the middle cerebral artery for 14 d significantly improved the neurological deficits, reduced brain infarction, and importantly, protected the cerebral vasculature as evidenced by the increased expression of an endothelial marker, von Willebrand factor, and better preservation of the cerebral vasculature, as viewed under a confocal microscope on rat brain perfused with FITC-labeled dextran. These results indicated that 2-BFI contributes to protection of neurovasculature. Understanding the molecular mechanisms could eventually lead to development of more effective therapies for stroke.

Eslicarbazepine acetate add-on for drug-resistant partial epilepsy

BACKGROUND

The majority of people with epilepsy will have a good prognosis, but up to 30% of patients will continue to have seizures despite several regimens of antiepileptic drugs. In this review we summarized the current evidence regarding eslicarbazepine acetate (ESL) when used as an add-on treatment for drug-resistant partial epilepsy.

OBJECTIVES

To evaluate the efficacy and tolerability of ESL when used as an add-on treatment for people with drug-resistant partial epilepsy.

SEARCH METHODS

We searched the Cochrane Epilepsy Group Specialized Register (3 November 2011), The Cochrane Central Register of Controlled Trials (CENTRAL issue 4 of 4, The Cochrane Library 2011), and MEDLINE (1948 to October week 4, 2011). There were no language restrictions. We reviewed the reference lists of retrieved studies to search for additional reports of relevant studies. We also contacted the manufacturers of ESL and experts in the field for information about any unpublished or ongoing studies.

SELECTION CRITERIA

Randomized placebo controlled double-blind add-on trials of ESL in people with drug-resistant partial epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and extracted data. Outcomes investigated included 50% or greater reduction in seizure frequency; seizure freedom; treatment withdrawal; adverse effects; and drug interactions. Primary analyses were by intention to treat. The dose response relationship was evaluated in regression models.

MAIN RESULTS

Four trials (1146 participants) were included; all studies were funded by BIAL. The overall relative risk (RR) with 95% confidence interval (CIs) for 50% or greater reduction in seizure frequency outcome was 1.86 (95% CI 1.46 to 2.36). Dose regression analysis showed evidence that ESL reduced seizure frequency with an increase in efficacy with increasing doses of ESL. ESL was significantly associated with seizure freedom (RR 3.04, 95% CI 1.44 to 6.42). Participants seemed more likely (albeit not significantly) to have ESL withdrawn for adverse effects (RR 2.26, 95% CI 0.98 to 5.21) but not for any reason (RR 1.07, 95% CI 0.73 to 1.57). The following adverse effects were significantly associated with ESL: dizziness (RR 3.09, 99% CI 1.76 to 5.43); nausea (RR 3.06, 99% CI 1.07 to 8.74); and diplopia (RR 3.73, 99% CI 1.19 to 11.64).

AUTHORS' CONCLUSIONS

Eslicarbazepine acetate reduces seizure frequency when used as an add-on treatment for people with drug-resistant partial epilepsy. The trials included in this review were of short-term duration and focused on adults.

Absence of the adenosine A2A receptor confers pulmonary arterial hypertension and increased pulmonary vascular remodeling in mice

BACKGROUND

Pulmonary arterial hypertension (PAH) is characterized by sustained elevation of pulmonary vascular resistance resulting from endothelial and smooth muscle cell dysfunction and collagen deposition in pulmonary vascular walls. In this study, we investigated the role of the adenosine A(2A) receptor (A(2A)R) in the development of PAH by determining the effect of genetic inactivation of A(2A)Rs on pulmonary vascular remodeling in mice.

METHODS AND RESULTS

We characterized hemodynamic, histological and ultrastructural changes in pulmonary vascular remodeling in A(2A)R knockout (KO) mice compared with their wild-type (WT) littermates after exposure to normoxia and hypoxic conditions. After exposure to normoxia, compared to WT mice, A(2A)R KO mice displayed: (1) increased right ventricular systolic pressures and an elevated ratio of the right ventricle over left ventricle plus septum (Fulton index), (2) increased wall area and thickness as well as enhanced smooth muscle actin immunoreactivity in pulmonary resistance vessels, (3) increased proliferating cell nuclear antigen-positive cells in pulmonary resistance vessels and (4) increased smooth muscle cells hypertrophy and collagen deposition in the adventitia of pulmonary arteriole walls as revealed by electron microscope. By contrast, histological analysis revealed no features of hypertensive nephropathy in A(2A)R KO mice and there was no significant difference in systemic blood pressure, and left ventricular masses among the 3 genotypes. Furthermore, following chronic exposure to hypoxia, A(2A)R KO mice exhibited exacerbated elevation in right ventricular systolic pressure, hypertrophy of pulmonary resistance vessels and increased cell proliferation in pulmonary resistance vessels, compared to WT littermates. Thus, genetic inactivation of A(2A)Rs selectively produced PAH and associated increased smooth muscle proliferation and collagen deposition.

CONCLUSIONS

Extracellular adenosine acting at A(2A)Rs represents an important regulatory mechanism to control the development of PAH and pulmonary vascular remodeling.

Neonatal endotoxin exposure suppresses experimental autoimmune encephalomyelitis through regulating the immune cells responsivity in the central nervous system of adult rats

Early-life exposure to bacterial endotoxin (lipopolysaccharide, LPS) affects the susceptibility to a variety of systemic organic inflammation in adulthood. To determine the long-term effects of neonatal LPS exposure on inflammatory responses in the central nervous system (CNS) in adulthood, we examined the effects on the development of experimental autoimmune encephalomyelitis (EAE) in adult rats as well as the potential regulatory immune mechanisms involved. The results showed that neonatal LPS exposure significantly reduced the morbidity (p<0.01) and severity (p<0.05) of EAE in adult rats, and decreased inflammatory cell infiltration and demyelination in the CNS compared with neonatal saline controls (p<0.05). Neonatal LPS-treated animals showed reduced activation of microglia and astrocytes, as detected by immunocytochemistry, accompanied by down-regulation of the pro-inflammatory cytokines interleukin-17 and interferon-gamma but up-regulation of anti-inflammatory cytokine interleukin-10 in the CNS (p<0.05). At the same time, cerebrum mRNA levels of the transcription factors T-bet and RORgammat were lower in neonatal LPS-compared with saline- treated animals (p<0.05) accompanied with increased STAT-6 and Foxp3 levels in the neonatal LPS-treated group (p<0.05). These findings suggest that early-life exposure to LPS could provide an important neuroprotective effect on the development of EAE in adult rats due to modulation of inflammatory responses in the CNS.

bFGF expression mediated by a hypoxia-regulated adenoviral vector protects PC12 cell death induced by serum deprivation

Basic fibroblast growth factor (bFGF) is a known neuroprotectant against a number of brain injury conditions such as cerebral ischemia. However, bFGF also regulates a plethora of brain developmental processes and functions as a strong mitogen. Therefore, unregulated long-term expression of bFGF in brain may potentially be tumorigenic, limiting its utility in brain therapy. Here, we report the successful construction of an adenoviral vector (Ad-5HRE-bFGF) expressing bFGF under the regulation of five hypoxia-responsive elements (5HRE) and a minimal cytomegalovirus promoter (CMVmp). Following hypoxia treatment in a hypoxic chamber with less than 1% of oxygen, Ad-5HRE-bFGF induced a significant and time-dependent expression of bFGF protein and the fluorescent tag, humanized GFP (hrGFP) protein, in infected PC12 cells. In contrast, normoxia treatment evoked extremely low level of bFGF and hrGFP expression, demonstrating that the 5HRE-CMVmp cassette was effective in regulating the expression of bFGF gene in response to hypoxia. More importantly, bFGF expressed by the Ad-5HRE-bFGF viral vector under the regulation of hypoxia was significantly neuroprotective against PC12 cell death evoked by serum deprivation. Taken together, these studies demonstrated the feasibility to express bFGF in a hypoxia-regulated fashion to provide neuroprotection. The Ad-5HRE-bFGF can be further developed as an effective tool to provide neuroprotection against hypoxia-induced brain diseases, such as cerebral ischemia.

Attenuation of ischemia-induced rat brain injury by 2-(-2-benzofuranyl)-2-imidazoline, a high selectivity ligand for imidazoline I(2) receptors

OBJECTIVE

The aim of this study was to determine whether 2-(2-benzofuranyl)-2-imidazoline, an imidazoline I(2) receptor ligand, could protect against cell death from brain injury and improve the functional outcome after focal cerebral ischemia in rats.

METHODS

Transient focal ischemia was induced by suture occlusion of the middle cerebral artery. Rats were intraperitoneally treated with a vehicle, 2-(2-benzofuranyl)-2-imidazoline or idazoxan immediately after focal ischemia. Infarct volume was assessed by 2,3,5-triphenyltrazolium chloride staining and neurobehavioral deficits were monitored. The volume of cell death in the penumbra after ischemia was determined by immunostaining using anti-cleaved caspase-3 antibody and terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL).

RESULTS

Both 2-(2-benzofuranyl)-2-imidazoline and idazoxan significantly improved the neurological score compared with the vehicle at 24 hours after focal ischemia. Treatment with 2-(2-benzofuranyl)-2-imidazoline or idazoxan also significantly reduced infarct volume and the number of both caspase-3- and TUNEL-positive cells in the penumbra compared with vehicle-treated rats (p<0.01 and p<0.05, respectively).

CONCLUSION

The results suggest the neuroprotective role of 2-(2-benzofuranyl)-2-imidazoline and idazoxan in focal cerebral ischemia, and may therefore represent useful targets for developing new treatments for stroke.

Neuroprotective effects of receptor imidazoline 2 and its endogenous ligand agmatine

Receptor imidazoline 2 (I₂) is one of the imidazoline receptors with high affinity for [³H]-idazoxan. Receptor I₂, being classified into I(₂A) and I(₂B) subtypes, is mainly localized to the outer membrane of mitochondria in liver, kidney and brain. Receptor I₂, displaying high similarity of sequence with monoamine oxidase-B (MAO-B), is structurally related to MAO-B, but the I₂ imidazoline binding site (I₂BS) with ligand is distinct from the catalytic site of MAO-B. Agmatine is the endogenous ligand of receptor I₂. Accumulating evidence have revealed that the activation of receptors I₂ may produce neuroprotective effects by increasing expression of glial fibrillary acidic protein (GFAP) in astrocytes, inhibiting activity of MAO, reducing calcium overload in cells. Agmatine exerts neuroprotection against ischemia-hypoxia, injury, glutamate-induced neurotoxicity by activating imidazoline receptors, blocking N-methyl-D-aspartate (NMDA) receptor, inhibiting all isoforms of nitric oxide synthase (NOS), and selectively blocking the voltage-gated calcium channels (VGCC). It would be expected that agmatine is one of the potential neuroprotective agents.

[Epidemiological investigation on an outbreak of angiostrongyliasis cantonensis in Wenzhou]

OBJECTIVE

To find out the cause and transmission factors of an outbreak of eosinophilic meningoradiculitis in Wenzhou City during October to November in 1997.

METHODS

In addition to a retrospective cohort study on 182 persons who had dined at a same restaurant of the city, etiological and immunoserological investigations were conducted.

RESULTS

Among 105 cases who had eaten the undercooked Ampullaria gigas in that restaurant, 47 cases were infected, the incidence rate was 44.8%; whereas none of the persons who did not eat the under-cooked Ampullaria gigas in that restaurant got the infection, the difference between the two groups being significant(P < 0.001). The incidence rate of the cases who had eaten 4 and more pieces of the undercooked Ampullaria gigas was 86.2%(25/29), while that of those who had eaten less than 4 pieces was 28.9%(22/76), the difference between the two being very significant (chi 2 = 27.83, P < 0.001, RR = 2.98). The third stage larvae of the Angiostrongylus cantonensis were found out from Ampullaria gigas living in the same locality, and the adult worms of Angiostrongylus contonensis were found out from the rats living in the locality else. The positive rate of serum anti-Angiostrongylus cantonensis antibody in the patients was 84.0%.

CONCLUSION

On the basis of the clinical, epidemiological, immunoserological and etiological investigations, an outbreak of the angiostrongyliasis cantonensis caused by eating undercooked Ampullaria gigas was confirmed.

[Relationship between levamisole and encephalitis syndrome]

The results of a cohort study of 92,346 labour population for probing the relationship between levamisole (LMS) and encephalitis syndrome was reported. There were five patients suffering from the disease in an exposed group (E) of 10,911 people within two months after taking LMS as an anthelmintic for mass treatment, the incidence of the disease is 4.58/10,000. The nonexposed population was divided into two control groups the first group (N1) includes 37,990 people living in the mass treatment villages and the other group (N2) consists of 43,445 people living in the adjoining villages without mass treatment. None in the two control groups suffered from the syndrome or any other encephalitis-like disease within the same period. Statistical tests for the differences between E and either N1 or N2 separately is highly significant. (between E and N1: P = 0.000553, P < 0.001; between E and N2: P = 0.000325, P < 0.001). The overall attributable risk (AR) is 45.8/100,000 and that for female is 93.8/100,000. However, the difference between the incidence rates of the disease in female and male is not statistically significant (P > 0.025). It is shown that LMS is obviously the causative factor of the disease.

[Clinical features of delayed polyneuropathy induced by acute methamidophos toxicosis in 74 cases]

A series of 74 cases of delayed polyneuropathy induced by acute middle to serious toxicosis with Methamidophos is analysed. It consists of 49 males and 25 females aged 12 to 45 years, mean age 22.6 years. The clinical features is similar to those of acute polyneuritis in common. The determination of nerve conduction velocity and electromyography show denervation lesions. The recovery cause is from 0.5 to 2 years. The proposal of the five requirements for diagnosis is listed. It is regarded that the pathogenesis of methamidophos-induced delayed polyneuropathy is the toxic effect produced by the "aging" of the phosphoryl-enzyme complex caused by the phosphorylation of a protein neurotoxic esterase (NTE) in the nervous system, and also is the autoimmuno disorder induced by the "aging" of the NTE being probably an immunological basis.