Association of cholesterol level with dopamine loss and motor deficits in Parkinson disease: A cross-sectional study.

BACKGROUND AND PURPOSE: Cholesterol is vital in neuronal function; however, the influence of cholesterol levels on parkinsonism is unclear. This study investigated the relationship between baseline total cholesterol (TC) levels, dopamine loss, and motor symptoms in drug-naïve Parkinson disease (PD). METHODS: This cross-sectional study enrolled 447 drug-naïve patients with PD who underwent dopamine transporter (DAT) imaging. Multivariate linear regression was used to investigate the effect of cholesterol levels on Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) total score and each subscore after adjusting for the covariates. An interaction analysis was performed to examine the interaction between TC levels and statin use on the UPDRS-III scores. RESULTS: No significant correlation was found between TC levels and DAT availability after adjusting for potential confounders. Multivariate linear regression showed that TC levels were significantly and negatively associated with the UPDRS-III total score (ß = -0.116, p = 0.013) and bradykinesia subscore (ß = -0.145, p = 0.011). Dichotomized analysis according to TC levels showed that TC levels were significantly associated with UPDRS-III total score, and rigidity, bradykinesia, and axial subscores only in the low TC group. There was an interaction effect between TC levels and statin use for the axial subscores (ß = -0.523, p = 0.025). Subgroup analysis showed that TC levels were significantly and negatively associated with the axial subscore in statin users; however, no association was found in statin nonusers. CONCLUSIONS: This study suggests that TC levels affect parkinsonian motor symptoms, especially in subjects with low cholesterol status, whereas the severity of axial motor symptoms is negatively associated with TC levels only in statin users.

Hyposmia may predict development of freezing of gait in Parkinson's disease.

To explore the effect of olfactory dysfunction on treatment of motor manifestations in Parkinson's disease (PD). The current longitudinal retrospective cohort study consecutively recruited 108 de novo PD patients. Of whom 29 were normosmia and 79 were hyposmia, respectively, which was determined by the Korean Version of Sniffin' Sticks Test II at the time of diagnosis. All the participants underwent serial clinical examinations including Unified Parkinson's Disease Rating Scale (UPDRS), Mini-Mental State Examination, and Montreal Cognitive Assessment. The normosmic group demonstrated a significantly greater reduction of the UPDRS III score (30.3 ± 5.9 to 21.9 ± 5.1) than that of the hyposmic group (34.5 ± 9.3 to 28.5 ± 8.1) from baseline to 1-year later (p, 0.003; Bonferroni correction for p < 0.0045). Of subdomains in UPDRS III, the axial domain revealed a remarkable decrease in the normosmic group. Further, the hyposmic group exhibited a higher development rate of freezing of gait (FOG) compared to the normosmic group (29/79 (36.7%) vs 2/29 (6.9%); p, 0.002) during 33.9 ± 7.7 months of the mean follow-up period. A Cox proportional hazards model demonstrated the hyposmia to be a significant risk factor for the future development of FOG (HR, 4.23; 95% CI 1.180-17.801; p, 0.05). Our data demonstrated the olfactory dysfunction to be a significant risk factor for the development of the FOG in PD. Hyposmic PD patients should be paid more careful attention to the occurrence of FOG in the clinical practice.

Behavioural and trait changes in parkinsonian patients with impulse control disorder after switching from dopamine agonist to levodopa therapy: results of REIN-PD trial.

OBJECTIVE: In this multicentre open-label trial, we compared behavioural and neuropsychiatric symptoms in Parkinson's disease (PD) patients with impulse control disorders (ICD) treated with dopamine agonists before and 12 weeks after substituting dopamine agonists with an equivalent dose of levodopa/carbidopa slow-release formulation. METHODS: Baseline characteristics of 50 PD patients with ICD were compared with those of 60 medicated and 40 drug-naive PD control groups. Neuropsychiatric trait changes in the PD-ICD group were investigated 12 weeks after the intervention. ICD behaviours were assessed via modified Minnesota Impulsive Disorders Interview (mMIDI), whereas parkinsonian severity and neuropsychiatric characters were systematically assessed with the Unified PD Rating Scale (UPDRS) and a predefined neuropsychological assessment battery. RESULTS: At baseline, ICD patients showed higher scores in the Neuropsychiatric Inventory and anxiety, anger and obsessive-compulsive traits compared with both PD control groups. In contrast, the three PD groups showed indifference in the impulsivity scales. At 12 weeks post intervention, ICD behaviours significantly improved (p<0.001, Δ modified MIDI score=‒5.27 ± 5.75) along with the UPDRS II daily activity scores (p=0.02, Δ=‒2.07 ± 4.53). Behavioural disinhibition tended to improve (p=0.06), although no significant changes were observed in the Neuropsychiatric Inventory and personality trait scores. Dopamine agonist withdrawal syndrome developed in 5.3% of the PD-ICD group. CONCLUSIONS: This study provides class IV evidence suggesting that switching from dopamine agonists to levodopa/carbidopa slow-release formulations alleviated ICD behaviours in PD patients leading to improvement in daily activities whereas neuropsychiatric traits associated with ICD persisted after the 12-week therapy. TRIAL REGISTRATION NUMBER: NCT01683253.

Neuropsychiatric Traits Associated with Refractory Impulse Control Disorder in Parkinson's Disease.

INTRODUCTION: Impulse control disorder (ICD) in Parkinson's disease (PD) is a critical nonmotor symptom with personality or neuropsychiatric traits contributing to ICD. OBJECTIVE: This study aimed to identify predictive traits for persistent or paradoxical aggravation of ICD after dopamine agonist substitution therapy for ICD in PD. METHODS: We conducted a case-control study using a database of a multicenter intervention trial for ICD in PD. The poor-outcome group was defined by showing paradoxical increases in ICD behaviors after the substitution of dopamine agonists with levodopa. We analyzed the pre-intervention personality traits associated with the poor outcome and also evaluated the risk traits for refractory ICD using a receiver-operating characteristic (ROC) curve analysis. RESULTS: The poor-outcome group showed higher levels of anger expression (p =0.007) and obsessive-compulsive traits (p =0.009) compared with the good-outcome group at the pre-intervention state. In the ROC curve analysis, the Obsessive-Compulsive Inventory showed the highest area under the curve with 80.0% sensitivity and 74.3% specificity in discriminating against the poor-outcome group. CONCLUSIONS: Our results suggest that assessment of obsessive compulsiveness may be useful for predicting the refractoriness of ICD behaviors in planning an interventional treatment for ICD in PD.

Validation of the Korean Version of the Scales for Outcomes in Parkinson's Disease-Sleep.

BACKGROUND: Sleep problems commonly occur in patients with Parkinson's disease (PD), and are associated with a lower quality of life. The aim of the current study was to translate the English version of the Scales for Outcomes in Parkinson's Disease-Sleep (SCOPA-S) into the Korean version of SCOPA-S (K-SCOPA-S), and to evaluate its reliability and validity for use by Korean-speaking patients with PD. METHODS: In total, 136 patients with PD from 27 movement disorder centres of university-affiliated hospitals in Korea were enrolled in this study. They were assessed using SCOPA, Hoehn and Yahr Scale (HYS), Unified Parkinson's Disease Rating Scale (UPDRS), Parkinson's Disease Sleep Scale 2nd version (PDSS-2), Non-motor Symptoms Scale (NMSS), Montgomery Asberg Depression Scale (MADS), 39-item Parkinson's Disease Questionnaire (PDQ39), Neurogenic Orthostatic Hypotension Questionnaire (NOHQ), and Rapid Eye Movement Sleep Behaviour Disorder Questionnaire (RBDQ). The test-retest reliability was assessed over a time interval of 10-14 days. RESULTS: The internal consistency (Cronbach's α-coefficients) of K-SCOPA-S was 0.88 for nighttime sleep (NS) and 0.75 for daytime sleepiness (DS). Test-retest reliability was 0.88 and 0.85 for the NS and DS, respectively. There was a moderate correlation between the NS sub-score and PDSS-2 total score. The NS and DS sub-scores of K-SCOPA-S were correlated with motor scale such as HYS, and non-motor scales such as UPDRS I, UPDRS II, MADS, NMSS, PDQ39, and NOHQ while the DS sub-score was with RBDQ. CONCLUSION: The K-SCOPA-S exhibited good reliability and validity for the assessment of sleep problems in the Korean patients with PD.

Differential effects of cholesterol levels on cognition according to body mass index in Parkinson's disease.

BACKGROUND: Cholesterol is an essential component of the neuronal cell membrane and is crucial for neuronal function; however, the role of cholesterol levels in Parkinson's disease (PD) is debatable. This study investigated the complex relationship between total cholesterol (TC) levels, body mass index (BMI), and cognition in patients with PD. METHODS: This study included 321 drug-naïve patients with PD who underwent dopamine transporter (DAT) imaging and baseline neuropsychological tests. Multivariate linear regression and Cox regression models were used to investigate the effect of TC levels on the composite score of each cognitive domain and dementia conversion after adjusting for covariates, respectively. Interaction analyses were performed to examine the interaction effect between TC levels and BMI on baseline cognition and dementia conversion. RESULTS: TC levels and cognition showed no significant relationship after adjusting for potential confounders. A significant interaction effect between TC levels and BMI was observed in frontal/executive function and dementia conversion. Further analyses showed that TC levels were positively associated with frontal/executive function in the under-/normal weight group (ß = 0.205, p = 0.013), whereas a negative relationship existed between TC levels and frontal/executive function in the obese group (ß = - 0.213, p = 0.017). Cox regression analyses also showed the differential effects of TC levels on dementia conversion according to BMI (under-/normal weight group: hazard ratio [HR] = 0.550, p = 0.013; obese group: HR = 2.085, p = 0.014). CONCLUSIONS: This study suggests a cross-over interaction between TC levels and BMI on cognitive symptoms in PD.

Opicapone to Treat Early Wearing-off in Parkinson's Disease Patients: The Korean ADOPTION Trial.

BACKGROUND: Increasing levodopa (L-dopa)/dopa decarboxylase inhibitor (DDCI) daily dose or adding a catechol-O-methyltransferase (COMT) inhibitor to levodopa/DDCI therapy are strategies used to manage wearing-off symptoms in Parkinson's disease (PD) patients. OBJECTIVES: To evaluate the COMT inhibitor opicapone versus an additional dose of levodopa to treat early wearing-off in PD patients. METHODS: ADOPTION was a randomized, parallel-group, open-label, Phase 4 study conducted in Korea. At baseline, eligible patients were randomized (1:1) to opicapone 50 mg (n = 87) or L-dopa 100 mg (n = 81) (added to current L-dopa/DDCI therapy) for 4 weeks. The main efficacy endpoint was change from baseline to end of study in absolute off time. Other endpoints included changes in on time, in Movement Disorder Society-Unified Parkinson's Disease Rating Scale and 8-item PD Questionnaire scores, and the Clinical and Patient Global Impression of Improvement/Change. RESULTS: The adjusted mean in absolute off time was significantly greater for opicapone 50 mg than for L-dopa 100 mg (-62.1 vs. -16.7 minutes; P = 0.0015). Opicapone-treated patients also reported a greater reduction in the percentage of off time (P = 0.0015), a greater increase in absolute on time (P = 0.0338) and a greater increase in the percentage of on time (P = 0.0015). There were no significant differences in other secondary endpoints. The L-dopa equivalent daily dose was significantly higher in the opicapone group (750.9 vs. 690.0 mg; P = 0.0247), when a 0.5 conversion factor is applied. CONCLUSIONS: Opicapone 50 mg was more effective than an additional 100 mg L-dopa dose at decreasing off time in patients with PD and early wearing-off.

Evaluating the validity and reliability of the Korean version of Scales for Outcomes in Parkinson's Disease-Cognition.

Objective: The Scales for Outcomes in Parkinson's Disease-Cognition (SCOPA-Cog) was developed to screen for cognition in PD. In this study, we aimed to evaluate the validity and reliability of the Korean version of the SCOPA-cog. Methods: We recruited 129 PD patients from 31 clinics with movement disorders in South Korea. The original version of the SCOPA-cognition was translated into Korean using the translation-retranslation method. The test-rest method with an intraclass correlation coefficient (ICC) and Cronbach's alpha coefficient were used to assess reliability. The Spearman's Rank correlation analysis with Montreal Cognitive Assessment-Korean version (MOCA-K) and Korean Mini-Mental State Examination (K-MMSE) were used to assess concurrent validity. Results: The Cronbach's alpha coefficient was 0.797, and the ICC was 0.887. Spearman's rank correlation analysis showed a significant correlation with the K-MMSE and MOCA-K scores (r = 0.546 and r = 0.683, respectively). Conclusions: Our results demonstrate that K-SCOPA-Cog exhibits good reliability and validity.

Carotid intima-media thickness in patients with carpal tunnel syndrome.

OBJECTIVES: We measured the carotid intima-media thickness, a surrogate marker of early atherosclerosis, in patients with carpal tunnel syndrome compared to a control group to evaluate the risk of atherosclerotic disease. METHODS: Between January 2011 and December 2011, female patients presenting to the outpatient neurology clinic for pain and paresthesia in the hands were screened for study enrollment. Patients 30 years or older were eligible for the study if they did not have a history of stroke or cardiovascular disease. RESULTS: During the study period, 111 patients (58 in the carpal tunnel syndrome group and 53 in the control group) were enrolled, with a mean age of 56 years (range, 32-79 years). There were no significant differences in baseline characteristics except maximum carotid intima-media thickness and body mass index. The maximum intima-media thickness was greater in the carpal tunnel syndrome group (mean ± SD, 1.05 ± 0.17 mm) than the control group (0.85 ± 0.22 mm; P < .0001). The body mass index was greater among the controls (P = .012). Simple linear regression analysis revealed that age (P < .0001), carpal tunnel syndrome (P < .0001), hypertension (P = .022), and systolic blood pressure (P = .034) were statistically significantly associated with increased intima-media thickness. Multiple linear regression analysis revealed that hypertension (P = .033), systolic blood pressure (P = .022), age (P < .0001), and carpal tunnel syndrome (P < .0001) were significantly associated with increased intima-media thickness, with carpal tunnel syndrome being the most influential factor (ß = 0.489). CONCLUSIONS: The maximum carotid intima-media thickness was significantly increased in patients with carpal tunnel syndrome compared to controls. Chronic inflammation beyond the traditional cardiovascular risk factors might be related to increased carotid intima-media thickness in patients with carpal tunnel syndrome.

Postural instability and cognitive dysfunction in early Parkinson's disease.

BACKGROUND: Postural instability is one of the most disabling features of Parkinson's disease, usually occurring in late and advanced stages. The aim of this study was to investigate the postural performance of early-stage de novo Parkinson's disease patients with no clinical postural instability using computerized dynamic posturography. We sought to understand the relationship between postural sway and disease severity and the relationship between postural instability quantitatively measured by computerized dynamic posturography and cognitive impairment in early-stage Parkinson's disease patients. METHOD: Thirty-one subjects with Parkinson's disease and 20 healthy controls were assessed by the computerized dynamic posturography protocol using the sensory organization test and the motor control test. A neuropsychological assessment was also administered. RESULTS: The mean equilibrium score for sensory organization test and the vestibular input ratio were significantly correlated with Hoehn-Yahr stage. No associations between motor latency for any motor control test condition and Hoehn-Yahr stage were found. The equilibrium score for sensory organization test correlated with the mini-mental status examination scores. There was a significant correlation between motor latency for large backward translation and mini-mental status examination scores. There were significant correlations between visual perception/construction/ memory of the neuropsychological battery test and the equilibrium score for sensory organization test and between verbal word learning test, controlled word association test and motor latency for large backward translation. CONCLUSION: These findings showed the postural instability present in early-stage (Hoehn-Yahr stage 2-2.5) Parkinson's disease. We also found a close relationship between postural instability and cognitive function in Parkinson's disease patients.

Carotid intima-media thickness in patients with idiopathic restless legs syndrome.

BACKGROUND: There have been no studies of carotid intima-media thickness (IMT) in idiopathic restless legs syndrome (iRLS) patients. The aims of this study were to evaluate the future risk of stroke in iRLS patients using computer software-assisted automated IMT measurement systems. METHODS: We measured the carotid IMT by high-resolution B-mode ultrasound with Intimascope software in 38 iRLS patients and 64 controls. RESULTS: The mean value of the maximum IMT in iRLS patients was significantly lower than that in controls (p < 0.05). In multiple linear regression analysis, younger age and the presence of iRLS remained statistically significant. Younger age or the presence of iRLS was highly correlated with a lower value of the maximum IMT (p < 0.001, p < 0.05). CONCLUSION: We suggest that iRLS patients may have a lower risk of progression of atherosclerosis.

Movement disorders associated with moyamoya disease: a report of 4 new cases and a review of literatures.

The aim of this study was to define the clinical characteristics of patients who developed movement disorders in association with moyamoya disease (MMD). Using PubMed and medical records of our hospital from 1985 to 2008, we searched for patients who developed movement disorders in association with MMD. This study included 38 patients described in previous studies and 4 patients found in the medical records. The onset of movement disorders was thought to be sudden. In 13 patients, the movement disorders were precipitated by hyperventilation or emotional stress. Twenty-seven of the 42 patients developed chorea, 4 patients developed dystonia, and 4 developed a mixture of both. The movement disorders of the remaining 7 patients were described as dyskinesia. A third of the 42 patients developed bilateral movement disorders, and their mean age was younger than that of those with unilateral movement disorders. In 37 of the 42 patients, brain imaging studies showed ischemic lesions, but the remaining 5 patients showed no parenchymal lesions. Cerebral perfusion studies showed hypoperfusion in the basal ganglia and in the cerebral cortical areas. Most patients improved whether they were treated or not. MMD must be included in the differential diagnosis of the sudden onset of dyskinesias, particularly chorea and focal dystonia. Even in patients with no parenchymal lesion in brain imaging studies, cerebral angiography and cerebral blood perfusion studies must be performed, if they develop a sudden onset or recurrent movement disorders preceded by emotional stress or hyperventilation.

Peripheral Neuropathy in de novo Patients with Parkinson's Disease.

PURPOSE: This study aimed to investigate the prevalence of peripheral neuropathy (PNP) and its related serum metabolites in de novo patients with Parkinson's disease (PD). PNP is a type of frequent comorbidity in PD. Although the administration of levodopa has been described as a presumptive risk factor in its development, few studies have explored its effect on unmedicated PD patients. MATERIALS AND METHODS: This study included 105 drug-naïve de novo PD patients. A standardized nerve conduction study (NCS) technique was used to evaluate motor or sensory neuropathy. We analyzed serologic tests including metabolic markers of vitamin B12, homocysteine (Hcy), and uric acid (UA). RESULTS: We found abnormal nerve conduction velocity findings in 24 out of 105 total patients. Among them, 20 patients showed a type of combined motor-sensory, while three were a type of pure sensory and one was a pure motor. Nine patients had carpal tunnel syndrome. PD with PNP group demonstrated higher serum levels of Hcy and UA compared to PD without PNP group. CONCLUSION: Our data demonstrated a potential role of Hcy and UA on PNP in de novo patients with PD. These results suggest the contribution of the inherent metabolic pathway in deterioration of the peripheral nervous system in PD.

Is an Isolated Weight-Holding Tremor a New Subtype of Isometric Tremor?

A weight-holding tremor is a rare type of hand tremor that occurs only when someone holds some weight. Here we report three cases of isolated weight-holding tremors, of which one patient was diagnosed with Parkinson's disease (PD) and the others as a variant of essential tremor (ET). A 68-year-old woman presented with a left-hand tremor that appeared only when she held objects with some weight. Her tremor was reminiscent of the re-emergent tremor of PD, and dopamine transporter imaging revealed reduced uptake at the right posterior putamen. A 21-year-old man and a 71-year-old woman also presented with similar weight-holding tremors. However, these tremors were not re-emergent, and no signs of parkinsonism were observed during follow-up. Although the underlying etiologies of these tremors differed, all three tremors worsened as the held weight increased. These tremors could be isolated isometric tremors, but further research is needed to clarify the nature of this rare tremor.

Validation of the Korean Version of the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale.

BACKGROUND AND PURPOSE: Impulse-control disorder is an important nonmotor symptom of Parkinson's disease (PD) that can lead to financial and social problems, and be related to a poor quality of life. A nationwide multicenter prospective study was performed with the aim of validating the Korean Version of the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale (K-QUIP-RS). METHODS: The K-QUIP-RS was constructed using forward and backward translation, and pretesting of the prefinal version. PD patients on stable medical condition were recruited from 27 movement-disorder clinics. Participants were assessed using the K-QUIP-RS and evaluated for parkinsonian motor and nonmotor statuses and for PD-related quality of life using a predefined evaluation battery. The test-retest reliability of the K-QUIP-RS was assessed over an interval of 10-14 days, and correlations between the KQUIP-RS and other clinical scales were analyzed. RESULTS: This study enrolled 136 patients. The internal consistency of the K-QUIP-RS was indicated by a Cronbach's α coefficient of 0.846, as was the test-retest reliability by a Guttman split-half coefficient of 0.808. The total K-QUIP-RS score was positively correlated with the scores for depression and motivation items on the Unified PD Rating Scale (UPDRS), Montgomery-Asberg Depression Scale, and Rapid-Eye-Movement Sleep-Behavior-Disorders Questionnaire. The total K-QUIP-RS score was also correlated with the scores on part II of the UPDRS and the PD Quality of Life-39 questionnaire, and the dopaminergic medication dose. CONCLUSIONS: The K-QUIP-RS appears to be a reliable assessment tool for impulse-control and related behavioral disturbances in the Korean PD population.

Subtypes of Sleep Disturbance in Parkinson's Disease Based on the Cross-Culturally Validated Korean Version of Parkinson's Disease Sleep Scale-2.

BACKGROUND AND PURPOSE: This study aimed to determine the clinimetric properties of the Korean version of Parkinson's Disease Sleep Scale-2 (K-PDSS-2) and whether distinct subtypes of sleep disturbance can be empirically identified in patients with Parkinson's disease (PD) using the cross-culturally validated K-PDSS-2. METHODS: The internal consistency, test-retest reliability, scale precision, and convergent validity of K-PDSS-2 were assessed in a nationwide, multicenter study of 122 patients with PD. Latent class analysis (LCA) was used to derive subgroups of patients who experienced similar patterns of sleep-related problems and nocturnal disabilities. RESULTS: The total K-PDSS-2 score was 11.67±9.87 (mean±standard deviation) at baseline and 12.61±11.17 at the retest. Cronbach's α coefficients of the total K-PDSS-2 scores at baseline and follow-up were 0.851 and 0.880, respectively. The intraclass correlation coefficients over the 2-week study period ranged from 0.672 to 0.848. The total K-PDSS-2 score was strongly correlated with health-related quality of life measures and other corresponding nonmotor scales. LCA revealed three distinct subtypes of sleep disturbance in the study patients: "less-troubled sleepers," "PD-related nocturnal difficulties," and "disturbed sleepers." CONCLUSIONS: K-PDSS-2 showed good clinimetric attributes in accordance with previous studies that employed the original version of the PDSS-2, therefore confirming the cross-cultural usefulness of the scale. This study has further documented the first application of an LCA approach for identifying subtypes of sleep disturbance in patients with PD.

Development of the Korean Academy of Medical Sciences Guideline for rating the impairment in the brain injured and brain diseased persons with motor dysfunction.

To develop an objective and scientific method to evaluate the brain injured and brain diseased persons with motor dysfunction, American Medical Association's Guides to the Evaluation of Permanent Impairment was used as an exemplar. After the motor dysfunction due to brain injury or brain disease was confirmed, active range of motion and muscle strength of affected extremities were measured. Also, the total function of extremities was evaluated through the assessment of activities of daily living, fine coordination of hand, balance and gait. Then, the total score of manual muscle test and functional assessment of impaired upper and lower extremity were added, respectively. Spasticity of upper and lower extremity was used as minus factors. Patients with movement disorder such as Parkinson's disease were assessed based on the degree of dysfunction in response to medication. We develop a new rating system based on the concept of total score.

Focal Task-Specific Lower Limb Dystonia Only When Walking Stairs: Is It a New Disease Entity?

Introduction: Focal task-specific dystonia in the lower limb or foot often occurs only during walking, running, hiking, or cycling. Several medications and botulinum toxin injection are effective in patients with this disorder. The objective of this study was to understand the spectrum of focal task-specific dystonia in the lower limb only when walking stairs and to compare other types of task-specific dystonia. Methods: All original articles and case reports were collected and reviewed using PubMed. In addition, all video clips of published cases were evaluated, and patients' clinical findings analyzed. The present study included 12 patients described in previous studies and five new Asian patients found in the medical records. Results: Most of the patients were women, and the onset age was 42 years. Ten patients were classified as the Kicking type, including three patients with the rKicking type, and six patients were considered as the Lifting type; however, only one patient was not included in any of the types. Symptoms in most of the patients did not improve with any medications or botulinum toxin injection. The symptoms of most patients did not change over a long time. Conclusion: Most patients showed the dystonic symptom when walking downstairs rather than upstairs. Psychogenic dystonia is a disease differentially diagnosed with this dystonia. Unlike other types of focal task-specific dystonia, the response to treatment was disappointing because most of the medications and botulinum toxin injection were not effective. The prognosis is completely different from that of other types of focal task-specific dystonia.

Trends in the Prevalence of Drug-Induced Parkinsonism in Korea.

PURPOSE: Discontinuation of offending drugs can prevent drug-induced parkinsonism (DIP) before it occurs and reverse or cure it afterwards. The aim of this study was to investigate the prevalence of DIP and the utilization of offending drugs through an analysis of representative nationwide claims data. MATERIALS AND METHODS: We selected DIP patients of ages ranging from 40 to 100 years old with the G21.1 code from the Korean National Service Health Insurance Claims database from 2009 to 2015. The annual standardized prevalence of DIP was explored from 2009 to 2015. Trends were estimated using the compound annual growth rate (CAGR) and the Cochran-Armitage test for DIP over the course of 6 years. Additionally, the utilization of offending drugs was analyzed. RESULTS: The annual prevalence of DIP was 4.09 per 100000 people in 2009 and 7.02 in 2015 (CAGR: 9.42%, p<0.001). Levosulpiride use before and after DIP diagnosis showed a clear trend for decreasing utilization (CAGR: -5.4%, -4.3% respectively), whereas the CAGR for itopride and metoclopramide increased by 12.7% and 6.4%, respectively. In 2015, approximately 46.6% (858/1840 persons) of DIP patients were prescribed offending drugs after DIP diagnosis. The most commonly prescribed causative drug after DIP diagnosis was levosulpiride. CONCLUSION: The prevalence of DIP has increased. To prevent or decrease DIP, we suggest that physicians reduce prescriptions of benzamide derivatives that have been most commonly used, and that attempts be made to find other alternative drugs. Additionally, the need for continuing education about offending drugs should be emphasized.