Jee Hyun Kim

Regional Cerebral Hyperperfusion with Ictal Dystonic Posturing: Ictal–Interictal SPECT Subtraction

Summary:  Purpose: Ictal–interictal single‐photon emission computed tomography (SPECT) subtraction was performed to find brain structures related to ictal dystonic posturing (DP) in patients with temporal lobe epilepsy (TLE).

Association of restless legs syndrome variants in Korean patients with restless legs syndrome.

STUDY OBJECTIVES Recent genome-wide association studies (GWAS) for Caucasians identified several allelic variants associated with increased risk of developing restless legs syndrome (RLS), also known as Willis-Ekbom disease. Although the pathogenic mechanisms of RLS are not entirely understood, it is becoming increasingly evident that many diseases such as RLS can be attributed to an epistasis. The study objectives were to evaluate whether the associations of RLS with all loci determined in previous GWAS for Caucasians can be replicated significantly for the Korean population and to elucidate whether an epistasis plays a role in the pathogenesis of RLS. DESIGN SETTING AND PARTICIPANTS DNA from 320 patients with RLS and 320 age- and sex-matched controls were genotyped for variants in the RLS loci. MEASUREMENTS AND RESULTS A significant association was found for rs3923809 and rs9296249 in BTBD9 (P < 0.0001 and P = 0.001, respectively); the odds ratio (OR) for rs3923809 was 1.61 (P < 0.0001) to 1.88 (P < 0.0001) and the OR for rs9296249 was 1.44 (P = 0.001) to 1.73 (P = 0.002), according to the model of inheritance. The OR for the interaction between rs3923809 in BTBD9 and rs4626664 in PTPRD was 2.05 (P < 0.0001) in the additive model, 1.80 (P = 0.002) in the dominant model and 2.47 (P = 0.004) in the recessive model. There was no significant association between genotypes of all tested single nucleotide polymorphisms and the mean value of serum iron parameters. CONCLUSIONS Our results suggest that the role of BTBD9 in the pathogenesis of restless legs syndrome is more universal across populations than previously reported and more efforts should be focused on the role of epistasis in the genetic architecture of restless legs syndrome.

The Effect of Ropinirole on the Quality of Life in Patients with Restless Legs Syndrome in Korea: An 8-Week, Multicenter, Prospective Study

Background and Purpose Dopamine agonists are first-line drugs for treating the symptoms of restless legs syndrome (RLS). However, few studies have investigated the effect of dopamine agonists on the quality of life (QoL) in RLS patients. We conducted a study to determine whether ropinirole exerts positive effects on the QoL in RLS patients and to analyze the underlying factors. Methods Primary RLS patients from eight medical centers were recruited in the study. They were evaluated in the baseline phase using various questionnaires including the Korean versions of the International Restless Legs Scale (K-IRLS), RLS QoL questionnaire (K-RLSQoL), and the Short Form 36 Health Survey (SF-36). After taking ropinirole for 8 weeks the same questionnaires were again completed as a re-evaluation. We analyzed the statistical difference using a paired t-test, a Pearsons correlation, and a stepwise multiple regression in order to identify the factors associated with the QoL change. Results A total of 107 subjects, including 65 (60.7%) females, completed this study. They were aged 51.68±14.80 years (mean±SD) and had a symptom duration of 8.8±9.0 months. After treatment with ropinirole, there were significant improvements on the K-RLSQoL, SF-36, and K-IRLS. The Pearsons correlation analysis showed that the improvement of QoL in RLS patients was significantly correlated with the severity of RLS (r=0.236, p<0.014) at baseline. Conclusions The results from this study suggest that treatment with ropinirole can improve the QoL in RLS patients. The improvement in the QoL is more related with the improvement of RLS symptoms.

Prevalence of Self-Perceived Snoring and Apnea and Their Association with Daytime Sleepiness in Korean High School Students

Background and Purpose There has been no nationwide population-based study of the prevalence of self-perceived snoring/apnea in Korean adolescents. The purpose of this study was to estimate prevalence of self-perceived snoring/apnea in Korean high-school students and to evaluate their association with daytime sleepiness. Methods An online survey was used to investigate 12,672 students at 75 high schools across the 15 nationwide districts of South Korea. The variables were obtained using a self-reported questionnaire. The students answered questions about self-perceived snoring/apnea during the past 30 days. Daytime sleepiness was measured using a validated Korean version of the Epworth Sleepiness Scale, which was modified for adolescents. Covariates were the sex, school grade, frequency of self-perceived snoring/apnea, body mass index, sleep duration during a school day, and subjective perception of sleep duration. Results The prevalence of self-perceived snoring/apnea was 22.8% (26.4% for males vs. 18.8% for females, p<0.001) and 9.2% (10.5% for males vs. 7.7% for females, p<0.001). Obesity was significantly associated with self-perceived snoring [odds ratio (OR)=2.18, 95% confidence interval (CI)=1.94–2.46] and apnea (OR=1.57, 95% CI=1.33–1.86). Multivariate analysis showed that any frequency of self-perceived snoring/apnea was significantly associated with excessive daytime sleepiness (EDS). The OR of EDS increased significantly with the frequency of snoring and apnea. Female, sleep duration of <5 hours during a school day, and subjective perceptions of insufficient and considerable sleep durations were also significantly associated with EDS. Conclusions The prevalence of self-perceived snoring/apnea was significantly higher in students who were male and obese. Students with self-perceived snoring/apnea exhibited more significant EDS and an increased risk of EDS as the frequency of snoring and apnea increased.

PF4.5 Altered Cortical Excitability in Patients with Charcot-Marie-Tooth Disease Combined with Restless Legs Syndrome

Background: Restless leg syndrome (RLS) was reported to be prevalent in patients with Charcot-Marie-Tooth disease (CMT), a hereditary motor and sensory neuropathy. We measured indices of transcranial magnetic stimulation (TMS) to investigate cortical and subcortical physiologic changes in CMT patients combined with RLS. Methods: Total 155 patients with genetically confirmed CMT (mean 35.6 year old, 75 male and 80 females) were evaluated, and 16 patients (10.3%) were confirmed to have definite RLS. Of these, 9 patients combined with CMT and RLS (mean 40.7 year old) were enrolled for this study compared with 14 ageand gender-matched control subjects (mean 40.1 year old). Genetic types of CMT patients were CMT1A (4/9), CMT2A (2/9), CMT1 (1/9), CMTX (1/9), and HSP27 (1/9). TMS was carried out to measure resting motor threshold (RMT), motor evoked potential (MEP) amplitudes and cortical silent periods (CSP), intracortical inhibition (ICI) and facilitation (ICF), and F-waves in the first dorsal interosseus (FDI) and the tibialis anterior (TA) muscles. Results: In patient group, RMT increased in TA muscles (p = 0.004), and MEP amplitudes decreased in FDI muscles at 120% (p = 0.017), 130% (p = 0.014), and 140% RMT (p = 0.003). CSP was shortened in FDI at 120% (p = 0.044), 130% (p = 0.006), and 140% RMT (p = 0.005), and in TA muscles at 110% (p = 0.004), 120% (p = 0.005), 130% RMT (p = 0.032), compared with the control group. ICI was not different, but ICF was exaggerated in FDI muscles of the patient group (p = 0.020). There was no difference in the latency of F-waves between the two groups. Conclusions: Our results suggest that the activity of the inhibitory interneurons decreased and the interaction between excitatory cortical pathways increased in the motor cortex of CMT patients combined with RLS. TMS is useful for investigating pathologic changes in cortical motor function, the intracortical circuits and the cortical/subcortical motor pathways in these patients. PF4.6 Effects of Pretreatment with Low-Frequency Repetitive Transcranial Magnetic Stimulation on Expressions of Hippocampus GAD65 and NMDAR1 in Rats with Pilocarpine-Induced Seizures