Diagnosis Of Essential Tremor Research Articles

Patient-reported Needs, Non-motor Symptoms, and Quality of Life in Essential Tremor and Parkinson's Disease.

BackgroundNon-motor symptoms, quality of life, service needs, and barriers to care of individuals with movement disorders are not well explored. This study assessed these domains within a sample of individuals with essential tremor (ET) and Parkinson's disease (PD).MethodsA survey exploring symptoms, needs, and barriers to care was disseminated to a convenience sample (N = 96) of individuals with a primary diagnosis of ET (N = 19) or PD (N = 77).ResultsSimilarities in overall quality of life and impact on daily functioning were found across individuals with ET and PD. Noteworthy differences included endorsement of different types of service needs and utilization patterns and fewer non-motor symptoms reported among those with ET (M = 6.1, SD = 2.4) than those with PD (M = 10.4, SD = 3.4). Non-motor symptoms significantly impacted movement disorder-related quality of life for both diagnostic groups, but this relationship was stronger for individuals with ET, t(12) = 3.69, p = 0.003, β = 0.73 than with PD, t(56) = 4.00, p<0.001, β = 0.47. Individuals with ET also reported higher rates of stigma (31.6% vs. 7.8%) and greater impact of non-motor symptoms on emotional well-being, R2 = 0.37, F(1, 13) = 7.17, p = 0.020.DiscussionThis is the first study to describe and compare the needs, barriers to care, and impact on quality of life of two distinct movement disorder groups. Our results support the recent efforts of the field to identify interventions to address the non-motor symptoms of movement disorders and indicate need for greater appreciation of the specific differences in symptoms and quality of life experienced across movement disorder diagnoses.

Patient-reported Needs, Non-motor Symptoms, and Quality of Life in Essential Tremor and Parkinson’s Disease

<strong>Background:</strong> Non-motor symptoms, quality of life, service needs, and barriers to care of individuals with movement disorders are not well explored. This study assessed these domains within a sample of individuals with essential tremor (ET) and Parkinson’s disease (PD). <strong>Methods:</strong> A survey exploring symptoms, needs, and barriers to care was disseminated to a convenience sample (<em>N</em>=96) of individuals with a primary diagnosis of ET (<em>N</em>=19) or PD (<em>N</em>=77). <strong>Results:</strong> Similarities in overall quality of life and impact on daily functioning were found across individuals with ET and PD. Noteworthy differences included endorsement of different types of service needs and utilization patterns and fewer non-motor symptoms reported among those with ET (M=6.1, SD=2.4) than those with PD (<em>M</em>=10.4, SD=3.4). Non-motor symptoms significantly impacted movement disorder-related quality of life for both diagnostic groups, but this relationship was stronger for individuals with ET, <em>t</em>(12)=3.69, <em>p</em>=0.003, <em>β</em>=0.73 than with PD, <em>t</em>(56)=4.00, <em>p</em>&lt;0.001, <em>β</em>=0.47. Individuals with ET also reported higher rates of stigma (31.6% vs. 7.8%) and greater impact of non-motor symptoms on emotional well-being, <em>R</em>²=0.37, <em>F</em>(1, 13)=7.17, <em>p</em>=0.020. <strong>Discussion:</strong> This is the first study to describe and compare the needs, barriers to care, and impact on quality of life of two distinct movement disorder groups. Our results support the recent efforts of the field to identify interventions to address the non-motor symptoms of movement disorders and indicate need for greater appreciation of the specific differences in symptoms and quality of life experienced across movement disorder diagnoses.

Intracranial Tumors in Parkinson’s Disease and Essential Tremor

Introduction: Several studies suggest that brain tumors occur more frequently in Parkinson’s disease (PD) than in the general population. Meanwhile data regarding the association of brain tumors and essential tremor (ET), the most common movement disorder, are scarce. Aim: Analysis of prevalence of intracranial tumors (ICT) in a clinical setting of ET versus PD patients. Material and Methods: We analyzed the medical records of 532 ET patients (179 males), aged 69 ± 8.9 years (32-91), with disease duration of 5.9 ± 6.6 years (1-50) and 323 PD patients (173 males), aged 68.4 ± 9.1 years (40-86), with disease duration of 5.1 ± 4.2 years (1-23), hospitalized for a 7-year period at the First clinic of Neurology, “Sveta Marina” University Hospital, Varna, Bulgaria. Results: We found 4 ICT (1.2%) (meningioma, osteoma, cavernoma and metastases) in the PD group, all of them discovered after the diagnosis of PD. In the ET group there were 16 ICT (3.0%), 12 of them discovered after the diagnosis of ET (7 meningiomas, 5 lipomas and 1 osteoma). Two pituitary adenomas, 1 meningioma and 1 glioma were diagnosed before ET symptoms. Conclusion: The prevalence of ICT in ET, compared with PD, is statistically insignificant. Our results might be due to the specific patient cohorts. Other reason may be the prevalence of females in the ET group, because it is known that meningiomas occur more frequently in women. Further investigation is needed to define more accurately the association between ICT, PD and ET in larger population settings.

Clinical classification of borderline cases in the family study of essential tremor: an analysis of phenotypic features.

BackgroundIn genetic research on essential tremor (ET), certain individuals may be particularly challenging to categorize diagnostically.MethodsIn the Family Study of Essential Tremor (>200 enrollees), 28 participants with borderline clinical findings who did not meet strict criteria for ET were assigned final diagnoses of ET. We scrutinized the clinical features of these cases and the sensitivity/specificity of certain features that best separated them from 19 unaffected individuals.ResultsBorderline ET cases differed from unaffected individuals in eight features: total tremor score, at least one kinetic tremor rating ≥1.5, at least one kinetic tremor rating ≥1.5 in the dominant arm, tremor rating during spiral drawing ≥1.5, higher spiral axis score, head tremor, complaint of tremor, and comment on tremor by others. The combination of at least one kinetic tremor rating ≥1.5 in the dominant arm and the presence of at least three of the remaining seven features predicted the clinician-assigned diagnosis in 88.6% of borderline ET vs. unaffected individuals (sensitivity 84.6%, specificity 94.4%).DiscussionIn a family study, a small number of clinical features characterized borderline ET, and a particular combination of these separated the majority of these borderline cases from normals. These analyses may help researchers minimize diagnostic misclassification.

Inter-Rater Agreement in the Clinical Diagnosis of Essential Tremor: Data from the NEDICES-2 Pilot Study.

BackgroundOur aim was to assess the diagnostic agreement among the neurologists in the Neurological Disorders in Central Spain 2 (NEDICES-2) study; these neurologists were assigning diagnoses of essential tremor (ET) vs. no ET.MethodsClinical histories and standardized video-taped neurological examinations of 26 individuals (11 ET, seven Parkinson’s disease, three diagnostically unclear, four normal, one with a tremor disorder other than ET) were provided to seven consultant neurologists, six neurology residents, and five neurology research fellows (18 neurologists total). For each of the 26 individuals, neurologists were asked to assign a diagnosis of “ET” or “no ET” using diagnostic criteria proposed by the Movement Disorders Society (MDS). Inter-rater agreement was assessed both with percent concordance and non-weighted κ statistics.ResultsOverall κ was 0.61 (substantial agreement), with no differences between consultant neurologists (κ = 0.60), neurology residents (κ = 0.61), and neurology research fellows (κ = 0.66) in subgroup analyses. Subanalyses of agreement only among those 15 subjects with a previous diagnosis of ET (11 patients) and those with a previous diagnosis of being normal (four individuals) showed an overall κ of 0.51 (moderate agreement).DiscussionIn a population-based epidemiological study, substantial agreement was demonstrated for the diagnosis of ET among neurologists of different levels of expertise. However, agreement was lower than that previously reported using the Washington Heights–Inwood Genetic Study of Essential Tremor criteria, and a head-to-head comparison is needed to assess which is the tool of choice in epidemiological research in ET.

Inter-Rater Agreement in the Clinical Diagnosis of Essential Tremor: Data from the NEDICES-2 Pilot Study

Inter-Rater Agreement in the Clinical Diagnosis of Essential Tremor: Data from the NEDICES-2 Pilot Study

A Comparative Kinematic Analysis of Cyclical Bending in Patients With Early Stages of Parkinson’s Disease and in Patients With Essential Tremor

Early stage Parkinson's disease (PD) shares certain symptoms with essential tremor (ET), which makes it difficult to differentiate between the two. We analyzed cyclical body bends to find kinematic parameters that are capable of differentiating among PD, ET and normal control (NC) subjects. A linear discriminant analysis of the joint angles showed a reliable distinction between NC and the two groups of patients, while differentiating reasonably well between PD and ET. PD patients showed difficulty performing hip segment rotation around the vertical axis, whereas ET patients demonstrated enlarged torso sway in the frontal plane. These findings suggest that kinematic parameters of body movement in the standing position are sensitive enough to serve as subclinical marks in the early diagnosis of PD and ET.

Dexterity Training Improves Manual Precision in Patients Affected by Essential Tremor

ObjectiveTo evaluate the effect of a short-term dexterity-training program on muscle tremor and the performance of hand precision tasks in patients with essential tremor (ET). DesignThree testing sessions: baseline, after 4 weeks without any interventions (control), and after 4 weeks of dexterity-training carried out 3 times per week. SettingBiomechanics research laboratory. ParticipantsPatients (N=8) with a diagnosis of ET. InterventionTraining program consisted of 12 dexterity training sessions where each session comprised 4 tasks involving both goal-directed manual movements and hand postural exercises. Main Outcome MeasuresTesting included an ET-specific quality of life questionnaire and postural and kinetic tremor assessments. Each training session was scored to evaluate the performance. ResultsAfter training, improvements were observed in the performance of the 2 goal-directed tasks (P<.01); however, postural and kinetic tremor did not change. ConclusionsThis study suggests that dexterity training could be effective in increasing fine manual control during goal-directed movements, which are known to be the most compromised in this pathology. The absence of a decrease in tremor severity highlights the necessity for developing this novel training technique further, perhaps over a longer period of time. This study could provide guidelines for the prescription of self-directed and personalized home-based exercises and will offer clinicians a treatment that might be used as an adjuvant or an alternative to the classical pharmacotherapy.

Mini Review: linkages between essential tremor and Parkinson’s disease?

Essential tremor (ET) and Parkinson’s disease (PD) are two of the most common movement disorders. Tremors are the primary symptoms of ET and of some PD patients, the two are often mistaken for each other. Especially since there are no available differentiate tests for the tremor of ET or PD, the early diagnoses mainly based on clinical assessments of medical symptoms, family and medication history, and examination by physicians. There is increasing evidence suggesting an association between ET and PD, such as a similar tremor frequency, overlapping resting tremors (a typical PD tremor), postural tremors (mainly in ET patients) in both ET and PD patients, and many ET patients develop PD later in life. Although it is difficult to make a differential diagnosis of ET and tremor-dominant PD based on clinical assessment, recent developments of objective measurements, such as brain imaging, neuropathology, and genetic analysis, has opened a helpful window for distinguishing ET from PD. In this mini review, we included literatures of ET and PD studies and discussed various advanced methods for differential diagnosis between ET and PD such as neuroimaging, genetic markers, tremor intensity and frequency, and drug-responses.

Prevalence of essential tremor in urban Lagos, Nigeria: a door-to-door community-based study

BackgroundEssential tremor (ET) is one of the commonest movement disorders though the prevalence varies globally. There is paucity of data on ET prevalence in sub-Saharan Africa. The study aimed to determine the prevalence of ET in a Nigerian community.MethodsThis door-to-door survey was conducted in two stages. In Stage 1, 3000 randomly selected residents of an urban centre in Lagos, Nigeria, were screened using a questionnaire to detect symptoms of movement disorder. 234 participants who responded positively regarding presence of tremors were rescreened using an ET-specific questionnaire, a face-to-face interview and neurological examination. Diagnosis of ET was based on the Movement Disorders Society (MDS) consensus diagnostic criteria for ET.ResultsOf the 3000 participants, forty responded positively to the ET screening questionnaire, of which 36 (19 females and 17 males) had a final diagnosis of ET, giving a crude prevalence of 12 per 1000 (95% CI = 8.1- 15.9). Gender specific prevalence was 10.3 /1000 in males and 14.3/1000 in females. Age specific prevalence increased with advancing age in both sexes. Age adjusted prevalence (WHO New world population) was 23.8 per 1000.ConclusionsWe documented a high prevalence of ET in this study, with typical increasing prevalence with advancing age as previously reported in other populations.

Cerebellar Pathology of a Dual Clinical Diagnosis: Patients with Essential Tremor and Dystonia

<strong>Background:</strong> Clinical studies have implicated the cerebellum in the pathogenesis of essential tremor (ET), and recent postmortem studies have identified structural changes in the ET cerebellum. While the basal ganglia have traditionally been implicated in dystonia, cerebellar involvement has been suggested as well, and a recent study showed Purkinje cell (PC) loss. We conducted a detailed postmortem examination of the brain in four individuals with clinical diagnoses of ET and dystonia, and hypothesized that pathological changes in the cerebellum would be greater in these four ET cases than in published ET cases without dystonia. <strong>Methods:</strong> After a complete neuropathological assessment, a standard parasagittal neocerebellar tissue block was harvested in each brain. One 7-μm thick section was stained with luxol fast blue/hematoxylin and eosin, and one section with the Bielschowsky method. We quantified PCs, torpedoes, heterotopic PCs, PC dendritic swellings, and basket cell changes. <strong>Results:</strong> Two ET+dystonia cases had more microscopic changes in the cerebellum than published ET cases; the other two cases had similar changes to published ET cases. <strong>Discussion:</strong> This is the first report that uses human autopsy tissue to study patients with both ET and dystonia. The findings were heterogeneous. Additional studies, with larger samples, are needed.

Cerebellar pathology of a dual clinical diagnosis: patients with essential tremor and dystonia.

Clinical studies have implicated the cerebellum in the pathogenesis of essential tremor (ET), and recent postmortem studies have identified structural changes in the ET cerebellum. While the basal ganglia have traditionally been implicated in dystonia, cerebellar involvement has been suggested as well, and a recent study showed Purkinje cell (PC) loss. We conducted a detailed postmortem examination of the brain in four individuals with clinical diagnoses of ET and dystonia, and hypothesized that pathological changes in the cerebellum would be greater in these four ET cases than in published ET cases without dystonia. After a complete neuropathological assessment, a standard parasagittal neocerebellar tissue block was harvested in each brain. One 7-µm thick section was stained with luxol fast blue/hematoxylin and eosin, and one section with the Bielschowsky method. We quantified PCs, torpedoes, heterotopic PCs, PC dendritic swellings, and basket cell changes. Two ET+dystonia cases had more microscopic changes in the cerebellum than published ET cases; the other two cases had similar changes to published ET cases. This is the first report that uses human autopsy tissue to study patients with both ET and dystonia. The findings were heterogeneous. Additional studies, with larger samples, are needed.

Genetic variants of α‐synuclein are not associated with essential tremor

Given the overlap between Parkinson's disease and essential tremor, we examined genetic variants in α-synuclein (SNCA) as risk determinants for essential tremor. Samples from 661 essential tremor subjects and 1316 control subjects from 4 participating North American sites were included in this study. Parkinson's disease samples (n = 427) were compared against controls. Twenty variants were selected for association analysis within the SNCA locus. Individual logistic regression analyses against essential tremor diagnosis were run for each variant and then combined using meta-analysis. Our results do not show a significant association between variants in the SNCA locus and risk of essential tremor, whereas the established association of SNCA variants with Parkinson's disease risk was observed. Whereas genetic factors are likely to play a large role in essential tremor pathogenesis, our results do not support a role for common SNCA genetic variants in risk for essential tremor.

Combined measures of movement and force variability distinguish Parkinson’s disease from essential tremor

Objective To examine whether behavioral and electrophysiological measures of motor performance accurately differentiate Parkinson’s disease (PD) and essential tremor (ET). Methods Twenty-four patients (12 PD; 12 ET) performed isometric force, ballistic movements, and tremor tasks. Receiver operating characteristic (ROC) analyses were conducted on all dependent measures that were significantly different between the two patient groups. Results Patients with PD were more impaired on measures of movement deceleration than ET. Patients with ET were more impaired on measures of force variability than PD. ROC analyses revealed that sensitivity and specificity were excellent when combining measures during the isometric force task (torque rise time and force variability; 92% sensitivity and 92% specificity; AUC = 0.97). When combining measures across the force and movement tasks, the ROC analysis revealed improved sensitivity and specificity (force variability and peak deceleration; 92% sensitivity and 100% specificity; AUC = 0.99). Conclusions Combining measures of force variability and movement deceleration accurately differentiate patients with PD from those with ET with high sensitivity and specificity. Significance If validated in a larger sample, these measures can serve as markers to confirm the diagnosis of PD or ET and thus, enhance decision making for appropriate treatments for patients with these respective diseases.

Inflammatory myopathy in a patient with postural and kinetik tremor

Essential tremor (ET) is a common neurological disease of unknown etiopathogenesis, possibly neurodegenerative, characterized by kinetic tremor at the arms. Here we reported the case of an HCV-positive patient with inflammatory myopathy, who did not develop typical neuromuscular signs or symptoms during at least 7years of hyperCKemia, in whom kinetic tremor of the arms was the prominent clinical feature, suggesting a possible diagnosis of ET. After 3months of treatment with corticosteroids/methotrexate, creatine kinase (CK) levels were nearly normal and the tremor was remarkably improved. To our knowledge, similar cases have not been previously reported. Postural tremor can be present in muscular diseases, but only very rarely tremor has been reported as a major clinical feature. Because inflammatory myopathies are potentially treatable conditions it is very important to consider this diagnosis. Our case suggests that in patients with isolated postural and kinetic tremor routine laboratory assays should include CK blood screening.

123I]FP‐CIT (DaTscan) SPECT Brain Imaging in Patients with Suspected Parkinsonian Syndromes

To review [(123)I]FP-CIT (Ioflupane I 123, DaTscan) SPECT imaging and its role in clinical practice. [(123)I]FP-CIT is a radiopharmaceutical that binds reversibly to striatal presynaptic dopamine transporters. We review the two principal multicenter clinical trials of [(123)I]FP-CIT SPECT imaging and provide additional, previously unreported information. Study 1 was a trial of [(123)I]FP-CIT SPECT in patients with early suspected parkinsonism that compared baseline scans to the consensus clinical diagnosis established 3 years later. Study 2 was a trial of [(123)I]FP-CIT SPECT in patients with established diagnoses of parkinsonian syndrome (PS) or essential tremor (ET). In Study 1, positive percent agreement (abnormal baseline scan and clinical diagnosis of PS at 36 months [n = 71]) was 78-79%. Negative percent agreement (normal baseline scan and a clinical diagnosis of non-PS at 36 months [n = 28]) was 97%. In study 2, positive percent agreement (abnormal scan and a clinical diagnosis of PS [n = 158]) was 92-97%. Negative percent agreement (normal scan and a clinical diagnosis of ET [n = 27]) was 74-96%. [(123)I]FP-CIT SPECT brain imaging is used to assist in the evaluation of adult patients with suspected PS and may help differentiate ET from PS as an adjunct to other diagnostic evaluations.

Prevalence of Essential Tremor in Araihazar, Bangladesh: A Population-Based Study

Background: Essential tremor (ET) is one of the most common neurological diseases. Few prevalence studies have been conducted in South Asia, and none in Bangladesh, one of the most populated countries in the world. We estimated the prevalence of ET in a population-based study in Araihazar, Bangladesh. Methods: As part of an in-person evaluation in a health outcomes study, each study participant produced 2 handwriting samples, from which ET diagnoses were assigned by 2 independent movement disorder neurologists. Results: The crude prevalence of ET (age ≧18 years) was 19/1,229 [1.5%, 95% confidence interval (CI) = 1.0–2.4], and was similar in men and women. The crude prevalence was 2.5% in participants aged ≧40 years and was one half that (1.3%) among younger participants (<40 years), although the difference did not reach statistical significance (p = 0.18). The age-adjusted prevalence (United States 2000 census) was 2.0% (95% CI = 1.2–2.8). Conclusion: The crude prevalence of ET in Araihazar, Bangladesh, was 1.5%. There is 1 other population-based study in a developing country (Turkey) which, like ours, did not restrict enrollment to middle-aged or elderly individuals and did not rely on screening questionnaires; the crude prevalence in the 2 studies is very similar.

Pharmacological Management of Essential Tremor

Essential tremor (ET) is a common movement disorder with clinical features that manifest with both motor (tremor and balance disorders) and non-motor (such as mild cognitive deficits and hearing loss) symptoms. The diagnosis of ET is based on the presence of an action tremor of greater severity than enhanced physiological tremor, without other identifiable causes. Patients with ET experience a decrease in the performance of their motor skills and social activities, and a decline in their quality of life. The pathophysiology of ET is still not clear. Pharmacotherapy for ET is indicated if the disease interferes with the patient's quality of life. Propranolol, a nonselective β-adrenergic receptor antagonist, and primidone, an antiepileptic, remain the standard treatments for ET. However, studies show that several other agents, including topiramate, gabapentin and zonisamide, might also be beneficial. Local injections of botulinum toxins and surgical interventions such as thalamic deep brain stimulation play a role as alternative options when pharmacological treatment is not satisfactory. Several new agents including 1-octanol, pregabalin and sodium oxybate are currently under investigation.

Clustering of dystonia in some pedigrees with autosomal dominant essential tremor suggests the existence of a distinct subtype of essential tremor

BackgroundThere is an ongoing debate whether essential tremor (ET) represents a monosymptomatic disorder or other neurologic symptoms are compatible with the diagnosis of ET. Many patients with clinically definite ET develop dystonia. It remains unknown whether tremor associated with dystonia represent a subtype of ET. We hypothesized that ET with dystonia represents a distinct subtype of ET.MethodsWe studied patients diagnosed with familial ET and dystonia. We included only those patients whose first-degree relatives met diagnostic criteria for ET or dystonia with tremor. This cohort was ascertained for the presence of focal, segmental, multifocal, hemidystonia or generalized dystonia, and ET.ResultsWe included 463 patients from 97 kindreds with autosomal dominant mode of inheritance (AD), defined by the vertical transmission of the disease. ET was the predominant phenotype in every ascertained family and each was phenotypically classified as AD ET. "Pure" ET was present in 365 individuals. Focal or segmental dystonia was present in 98 of the 463 patients; 87 of the 98 patients had ET associated with dystonia, one had dystonic tremor and ten had isolated dystonia. The age of onset and tremor severity did not differ between patients with "pure" ET and ET associated with dystonia. We did not observe a random distribution of dystonia in AD ET pedigrees and all patients with dystonia associated with ET were clustered in 28% of all included pedigrees (27/97, p < 0.001).ConclusionsOur results suggest that familial ET associated with dystonia may represent a distinct subtype of ET.

Familial associations of Alzheimer disease and essential tremor with Parkinson disease

We constructed a cohort of first-degree relatives of participants in a population-based case-control study of Parkinson disease (PD) and compared the occurrence of Alzheimer disease (AD) and essential tremor (ET) in relatives of PD cases and controls. We relied on proband interviews to assess family history in 372 probands with incident PD confirmed by a movement disorder specialist and 404 controls from three rural California counties. Overall, for the 2980 first-degree relatives of PD cases, the risk of AD was not increased compared with the 2981 relatives of controls. But relatives of younger onset PD cases (<or=60 years of age) were three times more likely to have received an AD diagnosis [hazard ratios (HR): 2.86; 95%CI: 1.44, 5.71]. Our data also suggest that some relatives of PD probands might be at a slightly increased risk of receiving an ET diagnosis, especially relatives of tremor dominant cases (HR: 1.69; 95%CI 0.99, 2.88), younger onset cases (HR: 2.03; 95%CI 0.93, 4.44), and male relatives (HR: 2.31; 95%CI 1.13, 4.73). In addition, fathers of cases were almost 15 years younger than fathers of controls when diagnosed with ET. Results were stable in sensitivity analyses. Our study suggests a familial susceptibility to AD amongst first-degree relatives of younger onset PD cases.