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Korchounov A, Tabatadze T, Spivak D, Rössy W, Krasnianski M. WITHDRAWN: MS related employment and disease modifying treatment in the German working population: 1994-2009. NeuroRehabilitation 2014:A43L74274U8V3018. [PMID: 24401825 DOI: 10.3233/nre-131031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Ahead of Print article withdrawn by publisher.
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Affiliation(s)
- A Korchounov
- Clinic of Neurology, Marienhospital Kevelaer, Kevelaer, Germany
| | - T Tabatadze
- Clinic of Neurology, Marienhospital Kevelaer, Kevelaer, Germany
| | - D Spivak
- Medical Center at Marienhospital Buer, Gelsenkirchen, Germany
| | - W Rössy
- Clinic of Neurology, Bad Schönborn, Germany
| | - M Krasnianski
- Clinic of Neurology, Marienhospital Kevelaer, Kevelaer, Germany Department of Neurology, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
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Winter Y, Epifanova-Bertschi N, Korchounov A. Development of screening batteries for neuropsychiatric comorbidity in elderly. J Neurosci Rural Pract 2013; 4:S9-S10. [PMID: 24174809 PMCID: PMC3808071 DOI: 10.4103/0976-3147.116424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
| | | | - Alexei Korchounov
- Department of Neurology, Clinic of Neurology, Marien hospital, Kevelaer, Germany
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Winter Y, Epifanova-Bertschi N, Sankowski R, Zhukova TV, Oertel WH, Dodel R, Korchounov A. Health-related quality of life and its determinants in the urban Russian population with major depressive disorder: a cross-sectional study. Int J Psychiatry Med 2012; 43:35-49. [PMID: 22641929 DOI: 10.2190/pm.43.1.c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Depressive disorders pose a major challenge to healthcare in the countries of the former Soviet Union. The objective of the current study was to evaluate health-related quality of life (HrQoL) and its determinants in outpatients with major depressive disorder in an urban Russian population. METHODS We consecutively recruited 100 urban Russian outpatients with major depression and 100 non-depressed controls who were matched for age and sex. The severity of their depression was assessed using the Hamilton Depression Rating Scale (HDRS). HrQoL was evaluated using the EuroQol (the EQ-5D and the visual analogue scale, EQ VAS). Independent determinants of HrQoL were identified using multiple regression analysis. RESULTS The mean EQ VAS score was 43.0 +/- 27.4 in patients with depression compared to 81.4 +/- 14.7 in the controls (p < 0.01). Out of the domains of the EQ-5D, "anxiety/depression," "usual activities," and "self-care" were the most impaired. Independent determinants of reduced HrQoL were: severity of depression according to the HDRS; violent suicide attempts; suicide attempts in the past; and drug addiction. CONCLUSIONS HrQoL is considerably reduced in Russians with major depression. The disease-specific patterns of HrQoL impairment and the independent determinants of HrQoL identified in our study could be addressed in focused healthcare programs and clinical trials. Comorbid drug addiction as a determinant of HrQoL should receive greater attention in the management of depressive disorders in urban Russian populations.
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Winter Y, Epifanova-Bertschi N, Korchounov A. Commentary. J Neurosci Rural Pract 2012. [DOI: 10.1055/s-0039-1697094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Affiliation(s)
- Yaroslav Winter
- Departments of Neurology, Philipps-University, Marburg, Germany
| | | | - Alexei Korchounov
- Departments of Neurology, Clinic of Neurology, Marienhospital Kevelaer, Germany
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Korchounov A, Tabatadze T, Spivak D, Rössy W. Epilepsy-related employment prevalence and retirement incidence in the German working population: 1994-2009. Epilepsy Behav 2012; 23:162-7. [PMID: 22236573 DOI: 10.1016/j.yebeh.2011.09.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 09/07/2011] [Accepted: 09/10/2011] [Indexed: 11/17/2022]
Abstract
Epilepsy-related employment prevalence and retirement incidence were investigated in the German working population from 1994 to 2009. The overall mean prevalence of employment of people with epilepsy was 5.1±0.2 per 1000 workers. The employment rate among people with epilepsy increased from 63.5% in 1994 to 65.9% in 2000 (0.4% annually) and then more steeply from 66.8% in 2001 to 76.9% in 2009 (1.4% annually). A prominent increase in rate of employment of people with epilepsy since 2001 was temporarily associated with approval of leviteracetam in 2000 (P<0.001, OR=8.3, CI=6.45-10.12). The overall mean employment rate of people with epilepsy was lower than that of the general population (68.5% vs 90.1%, P<0.001). The overall mean incidence of epilepsy-related retirement (RI) during the study was 4.6±1.6/1000, similar to the RI for people with other illnesses (5.1±0.8/1000), and the risk of retiring because of epilepsy was not higher than that for other illnesses over the entire study period (P=0.52, OR=1.11, CI=0.86-1.43). The RI among workers with epilepsy, however, sharply declined from 8.3/1000 in 1994 to 2.9/1000 in 2000 (-65%, < 0.001), followed by a slight increase and stabilization at 3.9/1000 workers between 2001 and 2009. The decline in RI among people with epilepsy was temporarily associated with legislation of the Law on Support of Employment in 1996 (P=0.032, OR=2.15, CI=1.17-2.89) and approval of lamotrigine in 1993 (P=0.024, OR=2.64, CI=2.17-3.88). These patterns suggest that drug treatment and legislative laws may have led to increased employment and reduced retirement rates for people with epilepsy.
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Affiliation(s)
- A Korchounov
- Clinic of Neurology, Marienhospital Kevelaer, Basilika Strasse 55, Kevelaer, Germany.
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Winter Y, Dodel R, Korchounov A, Grond M, Oertel WH, Back T. Clinical and pharmacological properties of new oral anticoagulants for the prevention of cerebral thromboembolism: Factor Xa and thrombin inhibitors. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/wjns.2012.21002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Winter Y, Epifanova-Bertschi N, Korchounov A. Commentary. J Neurosci Rural Pract 2012; 3:214-5. [PMID: 23308035 PMCID: PMC3410006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Affiliation(s)
- Yaroslav Winter
- Department of Neurology, Philipps-University, Marburg, Germany,Address for correspondence: Dr. Yaroslav Winter, Department of Neurology, Philipps-University Marburg, Baldingerstrasse, 35043 Marburg, Germany. E-mail:
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Abstract
Long-term potentiation (LTP) of synaptic efficacy is considered a fundamental mechanism of learning and memory. At the cellular level a large body of evidence demonstrated that the major neuromodulatory neurotransmitters dopamine (DA), norepinephrine (NE), and acetylcholine (ACh) influence LTP magnitude. Noninvasive brain stimulation protocols provide the opportunity to study LTP-like plasticity at the systems level of human cortex. Here we applied paired associative stimulation (PAS) to induce LTP-like plasticity in the primary motor cortex of eight healthy subjects. In a double-blind, randomized, placebo-controlled, crossover design, the acute effects of a single oral dose of the neuromodulatory drugs cabergoline (DA agonist), haloperidol (DA antagonist), methylphenidate (indirect NE agonist), prazosine (NE antagonist), tacrine (ACh agonist), and biperiden (ACh antagonist) on PAS-induced LTP-like plasticity were examined. The antagonists haloperidol, prazosine, and biperiden depressed significantly the PAS-induced LTP-like plasticity observed under placebo, whereas the agonists cabergoline, methylphenidate, and tacrine had no effect. Findings demonstrate that antagonists in major neuromodulatory neurotransmitter systems suppress LTP-like plasticity at the systems level of human cortex, in accord with evidence of their modulating action of LTP at the cellular level. This provides further supportive evidence for the known detrimental effects of these drugs on LTP-dependent mechanisms such as learning and memory.
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Affiliation(s)
- Alexei Korchounov
- Department of Neurology, Goethe-University Frankfurt, Frankfurt, Germany
| | - Ulf Ziemann
- Department of Neurology, Goethe-University Frankfurt, Frankfurt, Germany,Department of Neurology, Goethe-University, Schleusenweg 2-16, D-60528 Frankfurt am Main, Germany, Tel: +49 69 6301 5739, Fax: +49 69 6301 4498, E-mail:
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Winter Y, Korchounov A, Zhukova TV, Bertschi NE. Depression in elderly patients with Alzheimer dementia or vascular dementia and its influence on their quality of life. J Neurosci Rural Pract 2011; 2:27-32. [PMID: 21716831 PMCID: PMC3122998 DOI: 10.4103/0976-3147.80087] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Background: Alzheimer dementia (AD) and vascular dementia (VD) are the most common causes of dementia in the elderly. Depression is an important co-morbid disorder in these diseases, which is often challenging to recognize. We investigated the prevalence of depression in patients with AD and VD and estimated the influence of depression on the health-related quality of life (HrQoL) in these patients. Materials and Methods: We evaluated prevalence of depression in consecutively recruited patients with AD or VD (n= 98). Depression was diagnosed according to criteria of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) and scored using the Geriatric Depression Scale. The EuroQol (EQ-5D and visual analogue scale) was applied to evaluate HrQoL. The severity of cognitive impairment was measured by the Mini-Mental State Examination (MMSE). Multiple regression analysis was used to identify factors predicting severity of depression. Results: The prevalence of depression in AD/VD was 87%. In comparison to the general population, HrQoL measured on the visual analogue scale was reduced by 54% in patients with AD/VD. In the dimension “anxiety/depression” of the EQ-5D, 81% of patients with AD/VD had moderate or severe problems. Depression showed significant association with reduced HrQoL (P<0.01). Independent predictors of more severe depression were older age, male gender, better MMSE scores and being not married. Conclusions: Depression is a prevalent psychiatric co-morbidity in patients with AD/VD, which is often under-diagnosed being masked by cognitive impairment. Depression is a predictor of reduced HrQoL in elder people with AD/VD. Therefore, they should be screened for presence of depressive symptoms and receive adequate antidepressant treatment.
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Affiliation(s)
- Yaroslav Winter
- Department of Neurology, Philipps-University, Marburg, Germany, Parkinson Department
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Korchounov A, Meyer MF, Krasnianski M. Postsynaptic nigrostriatal dopamine receptors and their role in movement regulation. J Neural Transm (Vienna) 2010; 117:1359-69. [PMID: 21076988 PMCID: PMC3000910 DOI: 10.1007/s00702-010-0454-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 07/22/2010] [Indexed: 12/30/2022]
Abstract
The article presents the hypothesis that nigrostriatal dopamine may regulate movement by modulation of tone and contraction in skeletal muscles through a concentration-dependent influence on the postsynaptic D1 and D2 receptors on the follow manner: nigrostriatal axons innervate both receptor types within the striatal locus somatotopically responsible for motor control in agonist/antagonist muscle pair around a given joint. D1 receptors interact with lower and D2 receptors with higher dopamine concentrations. Synaptic dopamine concentration increases immediately before movement starts. We hypothesize that increasing dopamine concentrations stimulate first the D1 receptors and reduce muscle tone in the antagonist muscle and than stimulate D2 receptors and induce contraction in the agonist muscle. The preceded muscle tone reduction in the antagonist muscle eases the efficient contraction of the agonist. Our hypothesis is applicable for an explanation of physiological movement regulation, different forms of movement pathology and therapeutic drug effects. Further, this hypothesis provides a theoretical basis for experimental investigation of dopaminergic motor control and development of new strategies for treatment of movement disorders.
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Affiliation(s)
- Alexei Korchounov
- Parkinson Department, Marienhospital Kevelaer, Basilikastr. 55, 47612 Kevelaer, Germany.
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Buhmann C, Klucken J, Korchounov A, Schwarz M, Vieregge P, Jost W. Wann sollten wir mit der medikamentösen Therapie beim Morbus Parkinson beginnen? Fortschr Neurol Psychiatr 2010; 78 Suppl 1:S31-3. [DOI: 10.1055/s-0029-1245169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Jost WH, Buhmann C, Fuchs G, Greulich W, Hummel S, Korchounov A, Müngersdorf M, Schwarz M, Spiegel-Meixensberger M. Initial experience with ropinirole PR (prolonged release). J Neurol 2008; 255 Suppl 5:60-3. [PMID: 18787884 DOI: 10.1007/s00415-008-5008-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ropinirole is a non-ergolinic dopamine agonist, which has been used for over 10 years for the treatment of Parkinson's disease. A new formulation (PR = prolonged release) has been developed, which allows the drug to be released slowly (continuously) so that it only has to be given once daily. Switching from the previous ropinirole immediate release ( ropinirole IR) to the prolonged release (ropinirole PR) formulation at the nearest equivalent total daily dose, can take place overnight and the acceptance and tolerability are good. The advantages are once-daily dosing, faster titration with good tolerability and more stable plasma levels. The new formulation is regarded as valuable addition to the currently available medications.
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Wüllner U, Buhmann C, Hilker R, Hummel S, Korchounov A, Müller T, Paulus W, Schwartz A. Therapie der Zukunft. Akt Neurol 2007. [DOI: 10.1055/s-2007-970940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Scherm E, Reuter I, Kaps M, Korchounov A, Oechsner M. Heißhunger, Zwangsstörungen und Medikation bei Patienten mit Morbus Parkinson. Akt Neurol 2007. [DOI: 10.1055/s-2007-987903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Nord T, Reuter I, Korchounov A, Oechsner M. Sturzereignisse bei Morbus Parkinson. Akt Neurol 2007. [DOI: 10.1055/s-2007-987660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Korchounov A, Kessler K, Reuter I. Determinants of autonomic dysfunction in idiopathic Parkinson's disease. Akt Neurol 2007. [DOI: 10.1055/s-2007-987645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
Ischemic cerebral stroke is the leading cause of long-term disability among adults in industrialized countries. One fundamental but still not sufficiently solved question is how to improve disability after stroke. Here, evidence will be reviewed on how pharmacological treatment modulates plasticity and learning in the intact human motor cortex. It will be argued that these data may be useful for advancing the concepts of pharmacotherapy for recovery after stroke.
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Affiliation(s)
- Ulf Ziemann
- Department of Neurology, J. W. Goethe-University Frankfurt, Frankfurt am Main, Germany.
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Korchounov A, Ilić TV, Ziemann U. TMS-assisted neurophysiological profiling of the dopamine receptor agonist cabergoline in human motor cortex. J Neural Transm (Vienna) 2006; 114:223-9. [PMID: 16868794 DOI: 10.1007/s00702-006-0523-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2006] [Accepted: 05/03/2006] [Indexed: 01/01/2023]
Abstract
Dopamine plays a broad role in motor control and practice-dependent plasticity. Here we tested, in eight healthy subjects, the effects of the dopamine receptor agonist cabergoline on motor cortical excitability because the state of motor cortex can strongly influence practice-dependent plasticity. Cabergoline enhances practice-dependent plasticity but the mechanisms are unknown. We used transcranial magnetic stimulation for testing of motor cortical excitability. A single dose of 2 mg of cabergoline increased short-interval intracortical inhibition, a measure of excitability of GABA-dependent inhibitory neural circuits, and decreased various excitatory measures (motor evoked potential amplitude and short-interval intracortical facilitation). Other measures of motor cortical (motor threshold, cortical silent period duration), spinal (peripheral silent period duration, F-wave) and neuromuscular excitability (maximum M-wave) remained unchanged. This shift in the balance from excitation to inhibition may assist, by improving the 'signal-to-noise ratio' in motor cortex, in the positive modulating effect of cabergoline on practice-dependent plasticity.
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Affiliation(s)
- A Korchounov
- Motor Cortex Laboratory, Department of Neurology, Johann Wolfgang Goethe-University of Frankfurt, Frankfurt am Main, Germany
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Korchounov A, Bogomazov G. Employment, medical absenteeism, and disability perception in Parkinson's disease: A pilot double-blind, randomized, placebo-controlled study of entacapone adjunctive therapy. Mov Disord 2006; 21:2220-4. [PMID: 17044084 DOI: 10.1002/mds.21123] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The objective of this study was to test the impact of entacapone (ENT) addition to levodopa with a decarboxylase inhibitor (LD) in full-time-employed patients with Parkinson's disease (PD), focusing on retirement rates, medical absenteeism, self-perception of disability, as well as motor assessments of parkinsonism, motor fluctuations, and dyskinesias. Thirty full-time-employed PD patients (disease onset before age 60 years) and on optimized monotherapy with LD exhibiting minor motor fluctuations or dyskinesias were entered into a 2-year randomized double-blind placebo-controlled study of ENT adjunctive therapy. The outcome measures were the number of full-time-employed patients at study end, cumulative days of medical absenteeism, patient-completed disability assessments, diary records, and the Unified Parkinson's Disease Rating Scale-based measures of motor fluctuations and dyskinesias. LD + ENT treatment was associated with a lower retirement rate (2 [17%] of 12 vs. 6 [50%] of 12; P = 0.12), lower absenteeism rate (21.5 vs. 43.5 days; P < 0.0001), improved self-perception of disability progression over 2 years (change score 1.0 vs. 4.5; P < 0.0001), and lower scores for both motor fluctuations and dyskinesia assessments compared to LD monotherapy. In this pilot study, LD with ENT adjunctive therapy positively influenced employment rate over 2 years; this effect was associated with reduced motor complications and patient perceptions of stabilized disability.
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Korchounov A, Kessler KR, Yakhno NN, Damulin IV, Schipper HI. Determinants of autonomic dysfunction in idiopathic Parkinson’s disease. J Neurol 2005; 252:1530-6. [PMID: 16362830 DOI: 10.1007/s00415-005-0909-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2004] [Revised: 02/07/2005] [Accepted: 02/09/2005] [Indexed: 11/29/2022]
Abstract
OBJECTIVES To determine demographic or disease-related factors that may influence the severity of autonomic dysfunction in idiopathic Parkinson's disease (IPD). METHODS 532 patients with IPD aged between 55 and 75 years were included. Severity of autonomic dysfunction was assessed using a 9-item autonomic dysfunction score (ADS). In addition, several demographic factors (e. g. age, gender, comorbidities) and disease- related (e. g. motor stage, disease duration, antiparkinsonian therapy) factors were recorded. A group of 67 age-matched healthy volunteers served as a control group. Demographic and clinical data of this cross-sectional survey were analyzed by a logistic stepwise regression model to determine independent predictors of autonomic dysfunction. RESULTS IPD patients showed significantly higher ADS values than controls, even in the youngest age groups and in mild disease stages. Hoehn & Yahr (H&Y) stage, disease duration, age at onset and various therapy combinations all showed significant correlations with ADS. However, stepwise logistic regression revealed that age (OR 10.71; CI 7.17-16.0) and arterial hypertension (OR 3.05; CI 1.66-5.58) were the only independent risk factors associated with autonomic dysfunction. Linear regression indicated that ADS increases with age in controls as well as in patients, but with a significantly steeper slope in the latter. CONCLUSIONS Autonomic dysfunction as an inherent feature of IPD is present already in early disease stages. According to a logistic regression model, the severity of autonomic dysfunction in IPD is primarily related to demographic but not to disease-related factors. This and the differences in predictors for motor versus autonomic decline may indicate at least partly independent neurodegenerative processes.
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Affiliation(s)
- Alexei Korchounov
- Parkinson Clinic Bad Nauheim, Franz-Groedel-Str. 6, 61231 Bad Nauheim, Germany.
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Korchounov A, Ilic TV, Schwinge T, Ziemann U. Modification of motor cortical excitability by an acetylcholinesterase inhibitor. Exp Brain Res 2005; 164:399-405. [PMID: 15991031 DOI: 10.1007/s00221-005-2326-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2004] [Accepted: 02/23/2005] [Indexed: 11/28/2022]
Abstract
Acetylcholine powerfully modulates the excitability of neocortical neurones and networks. This study applied focal transcranial magnetic stimulation (TMS) to eight healthy subjects to test the effects of a single oral dose of 40 mg tacrine, an acetylcholinesterase inhibitor, on motor cortical excitability. It was found that tacrine decreased short-interval intracortical inhibition, and increased intracortical facilitation and short-interval intracortical facilitation. Motor thresholds, motor evoked potential amplitude, cortical silent period (CSP) duration, and measures of spinal and neuromuscular excitability remained unchanged. The effects peaked at 2-6 h and fully reversed after 24 h. All effects can be explained by a reduction of motor cortical GABAergic inhibitory neurotransmission via activation of presynaptic muscarinic M2 receptors, but other more complex mechanisms may also have contributed and are discussed. The findings predict that acetylcholine has the potential to promote plasticity and learning in human motor cortex.
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Affiliation(s)
- Alexei Korchounov
- Motor Cortex Laboratory, Department of Neurology, Johann Wolfgang Goethe-University of Frankfurt, Schleusenweg 2-16, 60528, Frankfurt am Main, Germany
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Abstract
This is a report on a case series of five patients with psychosis in Parkinson's disease who were treated successfully with an intramuscular injection of ziprasidone (10-20 mg) for acute agitation. No deterioration of motor function or other clinically relevant side effects were seen.
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Korchounov A, Schipper HI, Preobrazhenskaya IS, Kessler KR, Yakhno NN. Differences in age at onset and familial aggregation between clinical types of idiopathic Parkinson's disease. Mov Disord 2004; 19:1059-64. [PMID: 15372596 DOI: 10.1002/mds.20061] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Idiopathic Parkinson's disease (PD) can be subdivided by its patterns of motor symptoms into tremor-dominant (TDT), akinetic-rigid (ART), and mixed type (MT). Our objective was to determine whether age at onset and family history are different in these three types. In total, 366 patients with PD were assigned in a standardized approach to one of the three subtypes. Age at onset and family history were obtained in all patients and all presumably affected family members were examined. Mean ages at disease onset were similar in all three groups, but distribution of age at onset was markedly different: monophasic in TDT with a peak around 60 years, biphasic in ART with two peaks, one in the middle of the sixth decade (earlier onset, ART-EO), another during the first half of the seventh decade (later onset, ART-LO), and increasing with age only in MT patients A positive family history was significantly associated only with TDT (odds ratio = 5.7) and ART-EO (odds ratio = 7.8), but not with MT or ART-LO patients. Segregation analysis suggested an autosomal recessive mode of transmission in ART-EO and an autosomal dominant mode of transmission in TDT.
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Affiliation(s)
- Alexei Korchounov
- Department of Neurology, J.W. Goethe University, Frankfurt/Main, Germany.
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Ziemann U, Benilow S, Alle H, Korchounov A, Meintzschel F, Krakow K. Pharmacological Modulation of Plasticity. KLIN NEUROPHYSIOL 2004. [DOI: 10.1055/s-2004-832241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Korchounov A, Kessler KR, Schipper HI. Differential effects of various treatment combinations on cardiovascular dysfunction in patients with Parkinson's disease. Acta Neurol Scand 2004; 109:45-51. [PMID: 14653849 DOI: 10.1034/j.1600-0404.2003.00172.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVES Patients with Parkinson's disease (PD) frequently suffer from cardiovascular dysfunction, which may be enhanced to various extents by different antiparkinsonian drugs. MATERIALS AND METHODS We analysed electrocardiogram (ECG) abnormalities, cardiovascular reflexes (CVR) and orthostatic hypotension (OH) in 148 patients with idiopathic PD assigned to five different combination therapies of levodopa (LD) plus either bromocriptine (BRO), ropinirole (ROP), selegiline (SEL), anticholinergic (ACH) or amantadine (AMA) or to LD monotherapy before and after a 1-week washout of the add-on drug. Patients were matched for age and disease severity (Hoehn and Yahr stage 2-3). Rater-blinded cardiovascular testing was performed at baseline, and following a 1-week washout period of the add-on drugs. RESULTS We found that the incidence of cardiovascular dysfunction was generally higher in patients receiving a combination therapy compared with patients on LD monotherapy. ECG abnormalities were found in 40-52% of patients in combination therapy, but in only 20% of the patients receiving LD monotherapy. After discontinuation of BRO and SEL, there were significant improvements in ECG, OH and CVR. After washout of ACH and AMA, a significant improvement was found only in the CVR score. AMA and ROP were the add-on drugs with the least adverse cardiovascular effects. CONCLUSION We conclude that pre-existing cardiovascular autonomic dysfunction should be investigated and taken into account when deciding which combination therapy to choose in the treatment of parkinsonian patients.
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Affiliation(s)
- A Korchounov
- Department of Neurology, J. W. Goethe-University, Frankfurt/Main, Germany.
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Korchounov A, Ilić TV, Ziemann U. The α2-adrenergic agonist guanfacine reduces excitability of human motor cortex through disfacilitation and increase of inhibition. Clin Neurophysiol 2003; 114:1834-40. [PMID: 14499745 DOI: 10.1016/s1388-2457(03)00192-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To test the acute effects of the alpha2-adrenoceptor agonist guanfacine (GFC) on motor excitability in intact humans. METHODS Eight healthy right-handed adults received a single oral dose of 2 mg of GFC. Motor cortex excitability was tested by focal transcranial magnetic stimulation of the hand area of the left motor cortex. Motor evoked potentials (MEP) were recorded from the right abductor pollicis brevis muscle. In addition, spinal and neuromuscular excitability were tested. All measures were obtained immediately before GFC intake (baseline), and 2, 6, and 24 h later. RESULTS GFC decreased the slope of the MEP intensity curve, increased paired-pulse short-interval intracortical inhibition, and decreased paired-pulse intracortical facilitation and I-wave facilitation. These effects were maximal at 2-6 h and returned to baseline at 24 h. Motor threshold, cortical silent period, and the measures of spinal (peripheral silent period, F waves) and neuromuscular excitability (maximum M wave) remained unaffected. CONCLUSIONS This is the first study on the effects of an anti-noradrenergic drug on human motor cortex excitability. GFC reduced cortical excitability by disfacilitation and increased inhibition. These findings support the idea that anti-noradrenergic drugs are detrimental for cortical plasticity and learning which are down-regulated by disfacilitation or increased inhibition.
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Affiliation(s)
- Alexei Korchounov
- Clinic of Neurology, Johann Wolfgang Goethe-University Frankfurt, Theodor-Stern-Kai 7, D-60590, Frankfurt, Germany
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Abstract
Animal experiments show that motor recovery after focal brain injury is accelerated by the indirect norepinephrine agonist methylphenidate (MPH). The underlying mechanisms are unknown, but an MPH-induced increase in cortical excitability has been advocated. Here, we tested the acute effects of a single oral dose of 40 mg MPH (Ritalin) on motor cortical excitability in eight healthy subjects using focal transcranial magnetic stimulation. MPH increased the slope of the motor evoked potentials (MEP) intensity curve in a hand muscle, reduced short-interval intracortical inhibition, and increased I-wave facilitation. MEP threshold, cortical silent period and measures of spinal and neuromuscular excitability remained unaffected. Findings support the idea that MPH promotes accelerated motor recovery after lesion through facilitation and disinhibition.
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Affiliation(s)
- Tihomir V Ilić
- Clinic of Neurology, J.W. Goethe-University Frankfurt, Theodor-Stern-Kai 7, D-60590 Frankfurt am Main, Germany
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Abstract
Monoamines are powerful modulators of cortical function. Serotonin has complex excitatory and inhibitory effects on animal cortex. Here, the effects of a single oral dose (100mg) of the selective serotonin re-uptake inhibitor sertraline on human motor cortex excitability were investigated in healthy subjects. Transcranial magnetic stimulation was used to test motor threshold, motor evoked potential intensity curve, cortical silent period, paired-pulse inhibition and facilitation and I-wave facilitation. Sertraline resulted in a steeper intensity curve and in depressed paired-pulse facilitation (PPF). All other measures and spinal and neuromuscular excitability remained unaffected. The steeper intensity curve points to an increased excitability of the cortico-spinal neurone, while the depressed PPF suggests an enhanced control of the cortico-spinal neurone by inhibitory interneurones. These features may improve the signal-to-noise ratio of output cells in human motor cortex.
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Affiliation(s)
- Tihomir V Ilic
- Department of Neurology, J.W. Goethe-University Frankfurt, Theodor-Stern-Kai 7, D-60590 Franfurt am Main, Germany
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