Ya-nan Chen

Bio: Ya-nan Chen is an academic researcher from Chinese PLA General Hospital. The author has contributed to research in topics: Migraine & Headaches. The author has an hindex of 3, co-authored 4 publications receiving 50 citations.

High prevalence of headaches in patients with epilepsy

Abstract: To examine the association between headaches and epilepsy. Consecutive adult epileptic patients who went to the outpatient clinic of the Epilepsy Center of PLA General Hospital between February 01, 2012, and May 10, 2013, were recruited into this study. A total of 1109 patients with epilepsy completed a questionnaire regarding headaches. Overall, 60.1% of the patients (male: 57.2%; female: 63.8%) reported headaches within the last year. The age-weighted prevalence of interictal migraine was 11.7% (male 8.9%, female 15.3%), which is higher than that reported in a large population-based study (8.5%, male 5.4%, female 11.6%) using the same screening questions. The prevalence of postictal headaches was 34.1% (males 32.7%, females 35.2%), and the presence of preictal headaches was 4.5% (males 4.3%, females 5.2%). The prevalence of headache yesterday in the general population was 4.8% (male 3.0%, female 6.6%). Thus, the prevalence of headaches, including migraine, is higher in epileptic patients in China. The high prevalence of postictal headaches confirms the frequent triggering of a headache by a seizure. A much lower frequency of preictal headaches, a condition in which the real triggering effect of the headache on the seizure might be difficult to prove.

Long-term Effectiveness of Antiepileptic Drug Monotherapy in Partial Epileptic Patients: A 7-year Study in an Epilepsy Center in China

Abstract: Background: It is important to choose an appropriate antiepileptic drug (AED) to manage partial epilepsy.Traditional AEDs, such as carbamazepine (CBZ) and valproate (VPA), have been proven to have good therapeutic effects.However, in recent years, a variety of new AEDs have increasingly been used as first-line treatments for partial epilepsy.As the studies regarding the effectiveness of new drugs and comparisons between new AEDs and traditional AEDs are few, it is determined that these are areas in need of further research.Accordingly, this study investigated the long-term effectiveness of six AEDs used as monotherapy in patients with partial epilepsy.Methods: This is a retrospective, long-term observational study.Patients with partial epilepsy who received monotherapy with one of six AEDs, namely, CBZ, VPA, topiramate (TPM), oxcarbazepine (OXC), lamotrigine (LTG), or levetiracetam (LEV), were identified and followed up from May 2007 to October 2014, and time to first seizure after treatment, 12-month remission rate, retention rate, reasons for treatment discontinuation, and adverse effects were evaluated.Results: A total of 789 patients were enrolled.The median time of follow-up was 56.95 months.CBZ exhibited the best time to first seizure, with a median time to first seizure of 36.06 months (95％ confidential interval: 30.64-44.07).CBZ exhibited the highest 12-month remission rate (85.55％), which was significantly higher than those of TPM (69.38％, P =0.006), LTG (70.79％, P =0.001), LEV (72.54％,P =0.005), and VPA (73.33％, P =0.002).CBZ, OXC, and LEV had the best retention rate, followed by LTG, TPM, and VPA.Overall,adverse effects occurred in 45.87％ of patients, and the most common adverse effects were memory problems (8.09％), rashes (7.76％),abnormal hepatic function (6.24％), and drowsiness (6.24％).Conclusion: This study demonstrated that CBZ, OXC, and LEV are relatively effective in managing focal epilepsy as measured by time to first seizure, 12-month remission rate, and retention rate.

High prevalence of headaches in patients with

Abstract: Background: To examine the association between headaches and epilepsy. Methods: Consecutive adult epileptic patients who went to the outpatient clinic of the Epilepsy Center of PLA General Hospital between February 01, 2012, and May 10, 2013, were recruited into this study. A total of 1109 patients with epilepsy completed a questionnaire regarding headaches. Results: Overall, 60.1% of the patients (male: 57.2%; female: 63.8%) reported headaches within the last year. The age-weighted prevalence of interictal migraine was 11.7% (male 8.9%, female 15.3%), which is higher than that reported in a large population-based study (8.5%, male 5.4%, female 11.6%) using the same screening questions. The prevalence of postictal headaches was 34.1% (males 32.7%, females 35.2%), and the presence of preictal headaches was 4.5% (males 4.3%, females 5.2%). The prevalence of headache yesterday in the general population was 4.8% (male 3.0%, female 6.6%). Thus, the prevalence of headaches, including migraine, is higher in epileptic patients in China. Conclusions: The high prevalence of postictal headaches confirms the frequent triggering of a headache by a seizure. A much lower frequency of preictal headaches, a condition in which the real triggering effect of the headache on the seizure might be difficult to prove.

Serotonergic Modulation as Effective Treatment for Dravet Syndrome in a Zebrafish Mutant Model

Abstract: Dravet syndrome (DS) is a severe epilepsy syndrome that starts within the first year of life. In a clinical study, add-on treatment with fenfluramine, a potent 5-hydroxytryptamine (5-HT) releaser activating multiple 5-HT receptor subtypes, made 70% of DS children seizure free. Others and we recently confirmed the efficacy of fenfluramine as an antiepileptiform compound in zebrafish models of DS. By using a large set of subtype selective agonists, in this study we examined which 5-HT receptor subtypes can be targeted to trigger antiseizure effects in homozygous scn1Lab–/– mutant zebrafish larvae that recapitulate DS well. We also provide evidence that zebrafish larvae express the orthologues of all human 5-HT receptor subtypes. Using an automated larval locomotor behavior assay, we were able to show that selective 5-HT1D-, 5-HT1E-, 5-HT2A-, 5-HT2C-, and 5-HT7-agonists significantly decreased epileptiform activity in the mutant zebrafish at 7 days post fertilization (dpf). By measuring local field potential...

Headache in epilepsy: prevalence and clinical features

Abstract: Headache and epilepsy are two relatively common neurological disorders and their relationship is still a matter of debate. Our aim was to estimate the prevalence and clinical features of inter-ictal (inter-IH) and peri-ictal headache (peri-IH) in patients with epilepsy. All patients aged ≥ 17 years referring to our tertiary Epilepsy Centre were consecutively recruited from March to May 2011 and from March to July 2012. They underwent a semi-structured interview including the International Classification Headache Disorders (ICHD-II) criteria to diagnose the lifetime occurrence of headache.χ2-test, t-test and Mann–Whitney test were used to compare clinical variables in patients with and without inter-IH and peri-IH. Out of 388 enrolled patients 48.5 % had inter-IH: migraine in 26.3 %, tension-type headache (TTH) in 19.1 %, other primary headaches in 3.1 %. Peri-IH was observed in 23.7 %: pre-ictally in 6.7 %, ictally in 0.8 % and post-ictally in 19.1 %. Comparing patients with inter-ictal migraine (102), inter-ictal TTH (74) and without inter-IH (200), we found that pre-ictal headache (pre-IH) was significantly represented only in migraineurs (OR 3.54, 95 % CI 1.88-6.66, P < 0.001). Post-ictal headache (post-IH) was significantly associated with both migraineurs (OR 2.60, 95 % CI 1.85-3.64, P < 0.001) and TTH patients (OR 2.05, 95 % CI 1.41-2.98, P < 0.001). Moreover, post-IH was significantly associated with antiepileptic polytherapy (P < 0.001), high seizure frequency (P = 0.002) and tonic-clonic seizures (P = 0.043). Migraine was the most represented type of headache in patients with epilepsy. Migraineurs are more prone to develop pre-IH, while patients with any inter-IH (migraine or TTH) are predisposed to manifest a post-IH after seizures.

Pathophysiological Bases of Comorbidity in Migraine.

Abstract: Despite that it is commonly accepted that migraine is a disorder of the nervous system with a prominent genetic basis, it is comorbid with a plethora of medical conditions. Several studies have found bidirectional comorbidity between migraine and different disorders including neurological, psychiatric, cardio- and cerebrovascular, gastrointestinal, metaboloendocrine, and immunological conditions. Each of these has its own genetic load and shares some common characteristics with migraine. The bidirectional mechanisms that are likely to underlie this extensive comorbidity between migraine and other diseases are manifold. Comorbid pathologies can induce and promote thalamocortical network dysexcitability, multi-organ transient or persistent pro-inflammatory state, and disproportionate energetic needs in a variable combination, which in turn may be causative mechanisms of the activation of an ample defensive system with includes the trigeminovascular system in conjunction with the neuroendocrine hypothalamic system. This strategy is designed to maintain brain homeostasis by regulating homeostatic needs, such as normal subcortico-cortical excitability, energy balance, osmoregulation, and emotional response. In this light, the treatment of migraine should always involves a multidisciplinary approach, aimed at identifying and, if necessary, eliminating possible risk and comorbidity factors.

Hippocampal orexin receptors inactivation reduces PTZ induced seizures of male rats.

Abstract: Introduction Orexin has been shown to be involved in a number of physiological and behavioral processes including, feeding and metabolism, reward, nociception, and anxiety. Furthermore, orexin can cause increased neuronal excitability that gives rise to epileptic activity. The distribution of orexin receptor expression in the hippocampus, suggests a possible importance of orexin in the control of seizures in the temporal lobe epilepsy. Therefore, in this study, the effect of hippocampal orexin 1 and 2 receptors on seizure and glutamate and GABA (gamma-aminobutyric acid) contents was explored. Materials and methods Orexin 1 receptor (OX 1 R) antagonist (SB) and OX 2 R antagonist (TCS) were administrated bilaterally through separate cannulae into both hippocampi. Behavioral convulsions were provoked by intravenous pentylenetetrazol (PTZ) application model. The amount of total hippocampal glutamate and GABA contents was then measured by a biochemical method. Results SB (50 nmol) infusion reduced seizure stage, duration and decreased glutamate while GABA content was increased. SB (200 nmol) also reduced seizure stage, duration and glutamate content, without change of GABA content. TCS (20 nmol) infusion reduced seizure stage and duration without concomitant change in glutamate and GABA contents. Further, TCS (40 nmol) did neither affect the seizure nor the GABA, while decreased glutamate content. Co-administration of SB (50 nmol) with TCS (40 nmol) and also SB (200 nmol) with TCS (40 nmol) reduced seizure stage, duration and glutamate, but increased GABA content. Conclusion It is concluded that OX 1 R and OX 2 R antagonists reduce convulsive intensity, partially through alterations of hippocampal glutamate and GABA contents.

High prevalence of headaches in patients with epilepsy

Abstract: To examine the association between headaches and epilepsy. Consecutive adult epileptic patients who went to the outpatient clinic of the Epilepsy Center of PLA General Hospital between February 01, 2012, and May 10, 2013, were recruited into this study. A total of 1109 patients with epilepsy completed a questionnaire regarding headaches. Overall, 60.1% of the patients (male: 57.2%; female: 63.8%) reported headaches within the last year. The age-weighted prevalence of interictal migraine was 11.7% (male 8.9%, female 15.3%), which is higher than that reported in a large population-based study (8.5%, male 5.4%, female 11.6%) using the same screening questions. The prevalence of postictal headaches was 34.1% (males 32.7%, females 35.2%), and the presence of preictal headaches was 4.5% (males 4.3%, females 5.2%). The prevalence of headache yesterday in the general population was 4.8% (male 3.0%, female 6.6%). Thus, the prevalence of headaches, including migraine, is higher in epileptic patients in China. The high prevalence of postictal headaches confirms the frequent triggering of a headache by a seizure. A much lower frequency of preictal headaches, a condition in which the real triggering effect of the headache on the seizure might be difficult to prove.