Xiao-Qiu Shao

Risk factors for post-stroke seizures: a systematic review and meta-analysis.

PURPOSE To perform a systematic review and meta-analysis to identify risk factors associated with early seizure (ES) or late seizure (LS) onset in adults following stroke. DATA SOURCES Electronic databases (MEDLINE and EMBASE), archives of stroke or epilepsy patients, and bibliographies of relevant articles, which were written in English. STUDY SELECTION We included studies published since 1990 that reported the stroke and seizure outcomes of adult patients during follow-up. We independently performed title, abstract and full-text screening and resolved disagreements through discussion. DATA EXTRACTION Two authors performed the data extraction. We recorded all possible risk factors predictive of seizure onset. DATA SYNTHESIS We used odds ratios (ORs) or the mean difference (MD) to compare the pooled rates of seizure onset between the exposed group and the non-exposed group. All meta-analyses were performed with Review Manager Software. RESULTS Intracerebral hemorrhage (OR=1.88, 95% CI=1.43-2.47), cerebral infarction with hemorrhagic transformation (OR=3.28, 95% CI=2.09-5.16), stroke severity (OR=3.10, 95% CI=2.00-4.81, p<0.01, I(2)=0%; MD=3.98, 95% CI=1.06-6.90, p<0.01), and alcoholism (OR=1.70, 95% CI=1.23-2.34, p<0.01) were associated with a significantly greater probability of ES occurrence. There were significant effects of cortical involvement (OR=2.50, 95% CI=1.93-3.23) and stroke severity (MD=5.72, 95% CI=4.23-7.22, p<0.01, I(2)=0) on LS onset. However, there was no significant difference in the probability of single LS episode between patients with intracerebral hemorrhage and infarction stroke (OR=1.20, 95% CI=0.92-1.55). CONCLUSIONS Evidence suggests that cortical involvement, stroke subtypes and stroke severity are significant predictors of seizure onset following stroke. However, we did not find a significant difference in the rate of onset of single LS episodes between patients with intracerebral hemorrhage and cerebral infarction.

Temporal lobe epilepsy with amygdala enlargement: a subtype of temporal lobe epilepsy

BackgroundSome recent studies suggest that some imaging-negative temporal lobe epilepsy (TLE) had significant amygdala enlargement (AE). Contradictory data were also reported in previous studies regarding the association between AE and TLE. The present study was to investigate the clinical characters of a group of TLE with AE and compare the amygdala volume of the same patient before and after antiepileptic drugs treatment by a larger sample size.MethodsThis study recruited 33 mesial TLE patients with AE and 35 healthy volunteers. The clinical history, seizure semiology, electroencephalogram (EEG), fluorodeoxyglucose-positron emission tomography (FDG-PET) and amygdala volume were investigated. The amygdala volume were compared between ipsilateral and contralateral sides, TLE patients and 35 healthy controls, and patients at first and follow-up visit by 3.0 T MRI.ResultsAverage seizure onset age was 42.0 years (SD 14.3). All patients had complex partial seizures, fourteen had occasional generalized tonic-clonic seizures which often happened during sleep. Ninety percent patients suffered from anxiety or depression. Thirty percent patients had memory decline. Interictal epileptiform discharges appeared predominantly in the anterior or inferior temporal area ipsilateral to AE. Interictal FDG-PET showed regional glucose hypometabolism in the ipsilateral temporal lobe. No hippocampal sclerosis (HS) was suspected in all patients. 22 patients demonstrated good seizure control and significantly reduced volume of the enlarged amygdala after treatment (P < 0.01). The other 11 patients showed initial response to treatment, followed by a gradual increase in seizure frequency over time, and no volume change of the enlarged amygdala after treatment.ConclusionsTLE with AE probably represents a distinct nosological and probably less homogeneous syndrome which is most likely a subtype of TLE without ipsilateral HS. The chronic and long lasting inflammatory processes or focal cortical dysplasia could lead to amygdala enlargement possibly.

ASIC1a polymorphism is associated with temporal lobe epilepsy.

Recent in vitro and in vivo data show that acid-sensing ion channel 1a (ASIC1a) activation enhances neuronal excitability in the hippocampus and neocortex, indicating that ASIC1a might play a role in the generation and maintenance of epileptic seizures. The aim of this study was to investigate association of the ASIC1a gene with temporal lobe epilepsy (TLE) for the first time. Six tag single-nucleotide polymorphisms (SNPs) of the ASIC1a gene were selected and genotyped using polymerase chain reaction-restriction fragment length polymorphism in 560 TLE patients and 401 healthy controls. There was a significant allelic and genotypic association between rs844347:A>C and TLE compared with controls. The rs844347-A allele frequency was 88.1% in the patients and 83.0% in control subjects (OR=1.516, 95% CI 1.142-2.013, p=0.004). Furthermore, the haplotype analysis revealed a significant association with TLE. The results of this study demonstrate for the first time an association between an ASC1a variant allele and TLE in a Han Chinese population.

Limbic Encephalitis Associated with Anti-γ-aminobutyric Acid B Receptor Antibodies: A Case Series from China

Background:Autoimmune encephalitis associated with antibodies against &ggr;-aminobutyric acid B receptor (GABAB R) in patients with limbic encephalitis (LE) was first described in 2010. We present a series of Han Chinese patients for further clinical refinement. Methods:Serum and cerebrospinal fluid (CSF) samples from patients referred to the program of encephalitis and paraneoplastic syndrome of Peking Union Medical College Hospital were tested with indirect immunofluorescence. Clinical information of patients with anti-GABAB R antibody positivity was retrospectively reviewed, and descriptive statistical analysis was performed. Results:All eighteen anti-GABAB R antibody-positive cases had limbic syndromes, and electroencephalogram (EEG) or neuroimaging evidence fulfilled the diagnostic criteria of LE. Four patients had additional antibodies against Hu in serum and one had anti-N-methyl-d-aspartate receptor antibody in both sera and CSF. Seventeen (17/18) patients presented with new-onset refractory seizure or status epileptics. Twelve (12/18) patients had memory deficits, 11 (11/18) patients had personality change, 7 (7/18) patients had disturbance of consciousness, and 3 (3/18) patients showed cerebellar dysfunction. One patient with LE had progressive motor and sensory polyneuropathy. Lung cancer was detected in 6 (6/18) patients. Ten (10/18) patients showed abnormality in bilateral or unilateral mediotemporal region on magnetic resonance imaging. Ten (10/18) patients had temporal lobe epileptic activity with or without general slowing on EEG. Seventeen patients received immunotherapy and 15 of them showed neurological improvement. Four patients with lung cancer died within 1–12 months due to neoplastic complications. Conclusions:Our study demonstrates that most Han Chinese patients with anti-GABAB R antibody-associated LE have prominent refractory epilepsy and show neurological improvement on immunotherapy. Patients with underlying lung tumor have a relatively poor prognosis. Testing for anti-GABAB R antibodies is necessary for patients with possible LE or new-onset epilepsy with unknown etiology.

Association of apolipoprotein E polymorphisms with temporal lobe epilepsy in a Chinese Han population

Apolipoprotein E (ApoE) has been implicated as one of the susceptibility genes for temporal lobe epilepsy (TLE). Previous studies indicate that ApoE ɛ4 is associated with several disease-related traits including the increased risk of late posttraumatic seizures, earlier onset of TLE, refractory complex partial seizures, and postictal confusion. Contradictory data were also reported regarding the association between ApoE polymorphisms and TLE. The present study was designed to investigate whether ApoE ɛ4 is a risk factor for TLE and the above clinical variables, as well as to determine whether -491A/T polymorphism may independently alter the risk for TLE in a Chinese Han population. The ApoE and -491A/T polymorphisms were genotyped in 558 controls and 735 patients including 560 TLE patients using polymerase chain reaction-restriction fragment length polymorphism. A significant association was detected between prior trauma and the ApoE ɛ4 allele in TLE patients. However, no significant differences were observed in the genotype and haplotype distributions and allele frequencies of these two polymorphisms between cases and controls. Furthermore, there were no significant associations between these two polymorphisms and the other clinical variables examined. The study illustrates that the ApoE ɛ4 allele may be involved in the development of TLE in those patients with prior trauma in the Chinese Han population.

Status epilepticus-related etiology, incidence and mortality: A meta-analysis

Status epilepticus (SE) is a severe medical condition. To determine its epidemiology and outcome of SE, we performed a meta-analysis to investigate the etiology, incidence and mortality of SE. We searched PubMed and Embase between Jan 1, 2000, and Oct 31, 2016, with no regional restrictions, for observational studies of the etiology, incidence and mortality of SE. Forty-three studies were included in the meta-analysis. The pooled crude annual incidence rate, the pooled case fatality rate and the pooled crude annual mortality rate of SE were 12.6/100,000 (95% CI: 10.0-15.3), 14.9% (95% CI: 11.7-118.7) and 0.98/100,000 (95% CI: 0.74-1.22), respectively. Elderly subjects with SE had a higher case fatality rate (28.4% (95% CI: 17.7-42.3)) and crude annual incidence rate (27.1% (95% CI: 15.8-38.2)). The most important etiology-specific attributable fraction of patients with SE was acute symptomatic etiology (OR 0.411, 95% CI: 0.315-0.507). Age and economic income contributed to differences in SE incidence and short-term case fatality rate.

Prognostic factors for seizure outcome in patients with MRI-negative temporal lobe epilepsy: A meta-analysis and systematic review

PURPOSE To perform a systematic review and meta-analysis to identify predictors of postoperative seizure freedom in patients with magnetic resonance imaging (MRI)-negative temporal lobe epilepsy. METHOD Publications were screened from electronic databases (MEDLINE, EMBASE), epilepsy archives, and bibliographies of relevant articles that were written in English. We recorded all possible risk factors that might predict seizure outcome after surgery. We calculated odds ratio (OR) with corresponding 95% confidence intervals (95% CI) of predictors for postoperative seizure freedom. Heterogeneity was assessed with I(2). All meta-analyses were performed using Review Manager. RESULTS Epilepsy duration (OR=2.57, 95% CI=1.21-5.47, p<0.05, I(2)=1%) and ictal or interictal electroencephalographic anomalies precisely localized in the ipsilateral temporal lobe (OR=3.89, 95% CI=1.66-9.08, p<0.01, I(2)=0 and OR=3.38, 95% CI=1.57-7.25, p<0.05, I(2)=0, respectively) were significantly associated with a higher rate of seizure freedom after surgery. However, the positron emission tomography (PET) results were not predictive of postoperative seizure freedom (OR=2.11, 95% CI=0.95-4.65, p=0.06, I(2)=0). No significant difference in seizure freedom was observed between the positive and negative pathology groups (OR=1.36, 95% CI=0.70-2.63, p=0.36, I(2)=0). CONCLUSIONS A shorter epilepsy duration and scalp electroencephalogram (EEG) signals localized precisely in the temporal lobe predicted a better seizure outcome in patients with MRI-negative temporal lobe epilepsy.

Deep Brain Stimulation for Craniocervical Dystonia (Meige Syndrome): A Report of Four Patients and a Literature-Based Analysis of Its Treatment Effects.

The aim of this study was to report on four patients with craniocervical dystonia (CCD) treated with deep brain stimulation (DBS). In addition, we investigated the treatment efficacy and surgical outcome predictors by the review and analysis of previously published studies.

Hemispheric surgery for refractory epilepsy: a systematic review and meta-analysis with emphasis on seizure predictors and outcomes.

OBJECTIVE Conflicting conclusions have been reported regarding several factors that may predict seizure outcomes after hemispheric surgery for refractory epilepsy. The goal of this study was to identify the possible predictors of seizure outcome by pooling the rates of postoperative seizure freedom found in the published literature. METHODS A comprehensive literature search of PubMed, Embase, and the Cochrane Library identified English-language articles published since 1970 that describe seizure outcomes in patients who underwent hemispheric surgery for refractory epilepsy. Two reviewers independently assessed article eligibility and extracted the data. The authors pooled rates of seizure freedom from papers included in the study. Eight potential prognostic variables were identified and dichotomized for analyses. The authors also compared continuous variables within seizure-free and seizure-recurrent groups. Random- or fixed-effects models were used in the analyses depending on the presence or absence of heterogeneity. RESULTS The pooled seizure-free rate among the 1528 patients (from 56 studies) who underwent hemispheric surgery was 73%. Patients with an epilepsy etiology of developmental disorders, generalized seizures, nonlateralization on electroencephalography, and contralateral MRI abnormalities had reduced odds of being seizure-free after surgery. CONCLUSIONS Hemispheric surgery is an effective therapeutic modality for medically intractable epilepsy. This meta-analysis provides useful evidence-based information for the selection of candidates for hemispheric surgery, presurgical counseling, and explanation of seizure outcomes.

A polymorphism in CALHM1 is associated with temporal lobe epilepsy.

A recent study suggests that the P86L polymorphism (rs2986017) in the calcium homeostasis modulator 1 (CALHM1) gene interferes with calcium homeostasis and increases amyloid β (Aβ) levels. Moreover, in vitro and in vivo data show that both calcium homeostasis and high levels of Aβ play an important role in the induction and maintenance of epileptic seizures in hippocampus, indicating CALHM1 might play a potential role in pathophysiological pathways involved in temporal lobe epilepsy (TLE). The aim of this study was to investigate the genetic contribution of CALHM1 to TLE. Five single-nucleotide polymorphisms (SNPs) of CALHM1 were selected and genotyped using polymerase chain reaction restriction fragment length polymorphism in 560 patients with TLE and 401 healthy controls. We found a positive association between rs11191692 and TLE, but a negative result between rs2986017 and TLE. The rs11191692-A allele frequency was found in 32.4% of the patients and in 26.2% of control subjects (OR=1.35, 95% CI=1.10-1.65, uncorrected P=0.003, corrected P=0.015). Furthermore, the positive association between rs11191692 and TLE independent of apolipoprotein E ε4 was supported by five SNPs haplotype analysis. The results of this study provide the first evidence that the SNP rs11191692 in CALHM1 confers highly increased susceptibility to TLE.