SEARCH · PubMed Health

Results for “Essential Tremor”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

PubMedDate not supplied

Routine neurophysiologic tremor analysis as a diagnostic tool for essential tremor: a prospective study.

The objective of the current study was to investigate the diagnostic potential of the routine tremor neurophysiologic analysis for the diagnosis of essential tremor (ET) in patients with postural tremor syndrome. Three hundred consecutive outpatients attending for postural tremor were included. Accelerometry and surface electromyography was performed between 1 and 4 weeks after the first clinical visit. A final clinical diagnosis (mean follow-up period, 53 months) of the postural tremor syndrome was made by two neurologists blind to the neurophysiologic results. Six neurophysiologic criteria for the diagnosis of ET were applied to define the neurophysiologic examination as compatible or not compatible with ET (all criteria must be present): (1) rhythmic burst of postural tremor on EMG; (2) tremor frequency greater than or equal to 4 Hz; (3) absence of rest tremor or, if present, frequency 1.5 Hz lower than the postural tremor; (4) absence of tremor latency from rest to postural position; (5) changes of the dominant frequency peak less or equal to 1 Hz after the weight load test; and (6) no changes in tremor amplitude after mental concentration. The neurophysiologic criteria for ET showed a sensitivity of 97.7%, a specificity of 82.3%, a positive predictive value of 95.1%, a negative predictive value of 91.1%, and positive probability ratio of 5.5. The odds ratio was 198.43 (95% CI, 66.03 to 596.35). For the diagnosis of ET in patients with postural tremor, routine neurophysiologic tests have high diagnostic and predictive value that justifies its practice in movement disorders clinics.

Acceleration↗

PubMed2006

Jaw tremor: prevalence and clinical correlates in three essential tremor case samples.

The spectrum of involuntary movements seen in essential tremor (ET) is limited. Jaw tremor is one such movement. The prevalence and clinical correlates of jaw tremor have not been studied in detail. The objective of this study was to estimate the prevalence and examine the clinical correlates of jaw tremor in ET using ET cases from three distinct settings (population, tertiary-referral center, brain repository). All ET cases underwent a videotaped tremor examination in which tremors (including limb, head, voice, and jaw) were assessed. The prevalence [95% confidence interval (CI)] of jaw tremor was lowest in the population sample (7.5%; 3.9%-14.2%), intermediate in the tertiary-referral center (10.1%; 6.8%-14.7%), and highest in the brain repository (18.0%; 12.3%-25.5%; P = 0.03). Jaw tremor was associated with older age (P < 0.001), more severe action tremor of the arms (P < 0.001), and presence of head and voice tremor (P < 0.001). Jaw tremor was present in 4/14 (28.6%) ET cases with consistent rest tremor vs. 15/193 (7.8%) cases without rest tremor (odds ratio = 4.8; 95% CI = 1.3-7.0; P = 0.009). The prevalence of jaw tremor was 7.5% to 18.0% and was dependent on the mode of ascertainment, being least prevalent in a population-based sample. ET cases with jaw tremor had a more clinically severe and more topographically widespread disorder. The association in our study between jaw tremor and rest tremor, along with the published observation that jaw tremor can occur in Parkinson's disease (PD), raises the question whether jaw tremor in ET is a marker for subsequent conversion to PD.

Age Factors↗

PubMed1992

Effect of stereotactic thalamic lesion on essential tremor.

The cause of essential (low-frequency) tremor is unknown and its relation to physiological (high-frequency) tremor is unclear. We assessed essential tremor in one patient before and after a stereotactic thalamic lesion. The procedure changed the size of the tremor in the right hand but not in the left. Persistence of a low-frequency component suggested that essential tremor was an additional feature superimposed on physiological tremor in this patient. The focus of essential tremor seems to be an autonomous central generator that is independent of physiological tremor mechanisms.

Adult↗

PubMed1990

Preliminary report: activation of the cerebellum in essential tremor.

Several images of cerebral blood flow were recorded during inhalation of carbon-15-labelled carbon dioxide by positron emission tomography in four patients with essential tremor and four normal controls. Unilateral involuntary postural tremor in essential tremor patients was associated with blood flow significantly greater than that at rest in the contralateral sensorimotor cortex, both lateral premotor regions, and both cerebellar hemispheres. Of these regions, only the cerebellum was not activated in normal controls holding a posture without tremor or in essential tremor patients undergoing passive wrist movement. The increased flow in the cerebellum therefore seems to represent neural activity involved in tremor generation. It is proposed that essential tremor is due to oscillation within cerebello-olivary pathways, relayed by way of the thalamus and motor cortex to the spinal cord.

Administration, Inhalation↗

PubMed1987

Comparative studies on the effects of beta-adrenergic blockers in essential tremor.

To establish the criteria for the selection of a beta-adrenergic blocking agent (beta-blockers) suitable for the long-term treatment of tremor, 20 patients with essential tremor were treated with five different types of beta-blockers. All beta-blockers were effective for essential tremor, but their efficacy differed. The weaker the intrinsic sympathomimetic activity (ISA) and the more marked the membrane stabilizing activity (MSA), the more marked was the anti-tremor effect. Propranolol, which showed the strongest anti-tremor effect, had no ISA, but its long-term administration induced symptoms of heart failure, such as pretibial oedema, in most cases. In most of these cases, when propranolol was replaced by indenolol, which showed a very slight ISA, the pretibial oedema subsided and well-controlled tremor was maintained over a long period. With regard to efficacy and usefulness, it was thought that the beta-blockers with a very slight ISA and a marked MSA, such as indenolol, was most suitable for the long-term treatment of essential tremor.

Adrenergic beta-Antagonists↗

PubMed1997

Mapping of a familial essential tremor gene, FET1, to chromosome 3q13.

Essential tremor (ET), the most common movement disorder in humans, appears to be inherited as an autosomal dominant trait in many families. The familial form is called familial essential tremor (FET), which seems similar to sporadic essential tremor. ET is a cause of substantial disability, particularly in the elderly. The prevalence of Parkinson's disease and dystonia may be increased in families with ET, but other movement disorders are seldom encountered in these families. Here we report the results of a genome-wide scan for FET genes in 16 Icelandic families with 75 affected individuals, in whom FET was apparently inherited as a dominant trait. The scan, which was performed with a 10-cM framework map, revealed one locus on chromosome 3q13 to which FET mapped with a genome-wide significance when the data were analysed either parametrically, assuming an autosomal dominant model (lod score = 3.71), or non-parametrically (NPL Z score = 4.70, p < 6.4 x 10(-6).

Chromosome Mapping↗

PubMed2005

Essential tremor associated with focal nonnigral Lewy bodies: a clinicopathologic study.

BACKGROUND: Essential tremor is one of the most common neurological diseases. Its links with Parkinson disease (PD) are often debated. There have been few published postmortem studies. OBJECTIVE: To study our first case of essential tremor through the recently established Essential Tremor Centralized Brain Repository. DESIGN: Report of a case of a patient with a diagnosis of severe essential tremor for 46 years who exhibited no signs of parkinsonism. RESULTS: On postmortem examination, gross brain sections showed no abnormalities. Results of microscopic examination of hematoxylin-eosin-stained sections revealed that the locus coeruleus contained multiple Lewy bodies (LBs), although none were found in the substantia nigra, dorsal vagal nuclei, thalamus, substantia innominata, inferior olivary nucleus, or cerebellum. Immunochemical staining using antibodies directed against alpha-synuclein confirmed the presence of many LBs in the locus ceruleus and showed rare LBs in the substantia innominata and dorsal vagal nuclei. There were no LBs in the substantia nigra. CONCLUSIONS: Our patient had a very focal presence of LBs in the locus ceruleus, an anatomically restricted form of LB disease. This study provides support for the link between essential tremor and LB disease and raises the question as to what proportion of patients with essential tremor might have unusual forms of LB disease.

Aged↗

PubMed1984

Adrenergic beta-receptor sensitivity in essential tremor.

Adrenergic beta-receptor sensitivity of six male patients with essential tremor and six age-matched normal controls was assessed by measuring the response in the heart rate and postural tremor to incremental injections of the adrenergic beta-agonist isoprenaline. The relative increase in heart rate and tremor in essential tremor patients did not differ from that in normal controls. It is concluded that no major abnormality is likely to exist in the peripheral adrenergic beta-receptor sensitivity in essential tremor.

Adult↗

PubMed2001

Clinical and genetic study of essential tremor in the Italian population.

Essential tremor (ET) is one of the most common movement disorders. The pathogenesis is as yet unknown, although a genetic cause has long been recognised. Clinical and molecular evidence suggested that the ET gene contains a CAG expanded region. We examined a cohort of 240 Italian ET patients, classified as familial (193 cases) and sporadic (47 cases). The clinical manifestations of ET patients confirmed that the disorder is characterised by a large phenotypic variability. Repeat expansion detection (RED) approach did not demonstrate large CAG expansions. Six families were genotyped with 12 microsatellites markers of 2p and 3q regions and analysed according to parametrical methods. Lod scores values obtained in these families excluded the association of ET with 2p and 3q loci. Our findings confirm the presence of genetic heterogeneity and suggest that at least a third locus is involved in the pathogenesis of familial essential tremor.

Adolescent↗

PubMed1989

Homolateral disappearance of essential tremor after cerebellar stroke.

The case of a patient with essential tremor in whom tremor disappeared on the right side after a homolateral cerebellar infarct is reported. The pathophysiology of essential tremor remains unknown. Vascular and surgical lesions of dentorubrothalamic pathway have been reported to improve various kinds of tremor including essential tremor. In this patient, a lesion of this pathway related to the cerebellar infarct probably explains the homolateral cessation of essential tremor.

Aged↗

PubMed1984

Metoprolol and alpha-hydroxymetoprolol concentrations and reduction in essential tremor.

The relationship between reductions in essential tremor and concentrations of metoprolol and alpha-hydroxymetoprolol was examined in five patients with essential tremor after treatment with 0, 25, 50, and 75 mg metoprolol twice daily for 7 to 10 days. Serum concentrations of metoprolol and alpha-hydroxymetoprolol were measured simultaneous to serial accelerometry measurements of tremor over 8-hr periods. There was a relationship between degree of tremor reduction and steady-state metoprolol concentration. Time course of the drug and metabolite concentration correlated better with the time course of effect than with the time course of metoprolol concentration alone. Data suggest that the alpha-hydroxymetabolite of metoprolol may contribute to the reduction in essential tremor.

Adolescent↗

PubMed2006

Oxcarbazepine use in essential tremor.

OBJECTIVE: To report the novel finding of a significant improvement in essential tremor symptoms with oxcarbazepine in a patient with a suboptimal response to propranolol. CASE SUMMARY: A 40-year-old woman with a history of substance abuse complicated by essential tremor and neuropathic pain was admitted to our addictions unit with altered mental state due to escalating use of alprazolam. Alprazolam had been prescribed several months prior to admission for treatment of anxiety. The doses had risen to 5-10 mg/day during that period. Apparently, her essential tremor had responded inadequately to propranolol, but had responded well to alprazolam. She was started on a sedative/hypnotic withdrawal protocol, but did not require treatment with phenobarbital. She subsequently rated her tremor as "moderately severe." On discontinuation of the withdrawal protocol, oxcarbazepine 450 mg twice daily was initiated to treat her neuropathic pain, and the tremor improved, with a clinically significant reduction in tremor and a decreased pain score. DISCUSSION: Essential tremor is a common neurologic disorder with uncertain pathophysiology. Practice guidelines advocate the use of propranolol or primidone as first-line agents to treat essential tremor. Unfortunately, primidone has abuse potential and propranolol has variable pharmacokinetics; these characteristics limit their effectiveness in treating tremor. Our patient experienced a significant and sustained improvement in her tremor following the initiation of oxcarbazepine. To our knowledge, as of September 2, 2006, this is the first report of the use of oxcarbazepine in essential tremor. While the exact therapeutic action remains unclear, oxcarbazepine offers significant advantages compared with current first-line agents, including its good tolerability profile, the extended half-life of its metabolite, and lack of abuse potential. CONCLUSIONS: We report a case of essential tremor responding to oxcarbazepine. This drug offers several potential advantages over current first-line agents. Further research is warranted to test the robustness of this preliminary finding.

Adult↗

PubMed1999

Deep brain stimulation of the ventral intermediate nucleus of the thalamus for control of tremors in Parkinson's disease and essential tremor.

The beneficial effects of ventral intermediate nucleus (VIM) stimulation were evaluated in 20 patients with tremor refractory to medical therapy. Thalamic stimulation is a non-ablative procedure which has the advantage of a reversible, non-destructive lesion. Eleven patients [7 with Parkinson's disease (PD) and 4 with essential tremor (ET)] received unilateral VIM implantation, while 9 patients had staged bilateral VIM implantation (4 with PD, 5 with ET). PD patients showed a significant improvement in contralateral arm and leg rest tremor and ipsilateral leg rest tremor (p < 0.02) at a mean follow-up period of 16.2 +/- 7.0 months. Patients with PD did not demonstrate any significant decrease in medication use at follow-up. ET patients demonstrated significant improvement in postural and action tremor in the contralateral arm (p < 0.001), but no significant improvement in the contralateral leg tremor at follow-up. Significant improvements were also seen in ET patients in the Clinical Rating Scale for Tremor (p < 0.001) with respect to several activities of daily living at a mean follow-up of 14.9 +/- 8. 1 months. Deep brain stimulation is a safe and effective treatment for severe tremor refractory to medications. It is a highly effective, reversible, adaptable, and predictable procedure which avoids the complication of cognitive deficit seen in patients with bilateral thalamotomies.

Aged↗

PubMed2000

Surgical treatment of essential tremor.

Surgical treatment for essential tremor (ET) has been used since the early 1950s. Initially, different areas were targeted for tremor control. However, the optimal target was eventually determined to be the ventralis intermedius (VIM) nucleus of the thalamus. Thalamotomy improves contralateral tremor in more than 90% of patients. Long-term studies of thalamotomy indicate that the benefits continue in most patients. Persistent morbidity associated with thalamotomy, which occurs in less than 10% of patients, includes dysarthria, dysequilibrium, weakness, and cognitive impairment. Bilateral thalamotomy is associated with substantial morbidity and is usually avoided. Studies demonstrate that chronic stimulation of the VIM is safe and effective for tremor. Adverse effects of chronic stimulation include paresthesia, dysarthria, dysequilibrium, and localized pain. In many patients, bilateral thalamic stimulation is performed without a substantial increase in morbidity. ET patients with disabling medication-resistant tremor are reasonable candidates for these stereotactic procedures.

Essential Tremor↗

PubMed1999

A randomized placebo-controlled comparative trial of gabapentin and propranolol in essential tremor.

BACKGROUND: New medication is needed to treat essential tremor. Preliminary evidence suggests that gabapentin may be effective in the treatment of this disorder. OBJECTIVE: To study the effects of gabapentin in a comparative, double-blind, crossover, placebo-controlled trial of patients who have essential tremor. PATIENTS AND METHODS: 16 patients with essential tremor (6 with a new onset and 10 with a 2-week washout period of previous treatment with propranolol hydrochloride) received gabapentin (Neurontin), 400 mg 3 times daily; propranolol hydrochloride, 40 mg 3 times daily; and placebo for 15 days with a 1-week washout period between treatments. MAJOR OUTCOME MEASURES: Major outcome evaluations consisted of a Tremor Clinical Rating Scale, accelerometric recordings, and a self-reported disability scale obtained before drug intake on study days 1 and 15 of each treatment period. In addition, the initial (day 1) and superimposed (day 15) drug effects were studied before and 2, 4, 6, and 8 hours after drug intake. RESULTS: At day 15, both gabapentin and propranolol demonstrated significant and comparable efficacy in reducing tremor from baseline in all tremor measures. The initial drug effects evaluated through accelerometry revealed no significant changes with the use of a placebo, but gabapentin and propranolol use significantly reduced tremor power. CONCLUSION: Gabapentin may be useful for the treatment of essential tremor.

Acetates↗

PubMed1985

Association between essential tremor and Parkinson's disease.

To examine a possible relationship of essential tremor to Parkinson's disease (PD), 130 patients with essential tremor were studied. Twenty-five patients had both essential tremor and PD. These 25 patients were matched for age and duration of PD symptoms with 25 patients who had idiopathic PD. Bradykinesia, postural instability, and gait difficulty were more severe in the patients with idiopathic PD. Degree of tremor, rigidity, and functional disability did not differ in the two groups. The prevalence of PD in the population with essential tremor was 24 times greater than expected. This study suggests that some patients with essential tremor have a genetically increased risk for PD.

Adolescent↗

PubMed2007

A double-blind placebo-controlled trial of zonisamide (zonegran) in the treatment of essential tremor.

Medical therapy for essential tremor (ET), a common movement disorder, is often inadequate. We performed a double-blind placebo-controlled randomized trial to evaluate the efficacy and tolerability of zonisamide (ZNS), an antiepileptic agent, in treating ET. Twenty patients (mean age, 60 +/- 15 years) with ET were randomized to receive ZNS or placebo. ZNS was initiated at a dosage of 100 mg/day and escalated to 200 mg/day at day 14. Patients were evaluated by accelerometry and the Fahn-Tolosa-Marin (FTM) rating scale at baseline and days 14 and 28, as well as the Clinical Global Impression (CGI-C) scale at day 28. At endpoint, subjects assigned to ZNS were taking a mean dosage of 160 +/- 50 mg/day. There were no significant improvements in the FTM total score or its subsections. Tremor amplitude as assessed by accelerometry significantly improved in the ZNS group compared to the placebo group at endpoint relative to baseline (-0.50 +/- 0.72 vs. 0.30 +/- 0.79 m/s(2); P = 0.03). On the CGI-C, 60% (n = 6) of patients in the ZNS group felt that their tremor was unchanged, while the remaining patients felt that their tremor was "minimally improved." Thirty percent (n = 3) of patients taking ZNS discontinued the study due to side effects (fatigue, headache, paresthesias) while taking 100 mg per day. ZNS did not provide significant improvements in clinical rating scales at study endpoint compared to placebo and was only modestly well tolerated. ZNS was effective in reducing tremor amplitude as measured by accelerometry.

Anticonvulsants↗

PubMed2005

Factor structure of motor signs in essential tremor.

Motor signs in essential tremor (ET) are varied. Patients may have limb tremors, including postural, kinetic (e.g. writing, pouring), and rest tremors, head tremor, voice tremor, or chin tremor. Factor analysis allows one to determine whether these signs fall into a smaller number of discrete domains. Such an analysis has not been performed on a group of ET cases. ET cases (n = 168) were recruited from the Neurological Institute of New York and a videotaped examination was performed. A factor analysis was performed on 17 motor items. Four distinct factors emerged, explaining 68.7% of the total variance. These were factor I (action tremor in the dominant arm), factor II (action tremor in the nondominant arm), factor III (tremor at rest) and factor IV (chin tremor, head tremor, and voice tremor). The demonstration of these four factors will be of potential use for pathological and genetic studies as well as interventional studies, as will be discussed.

Aged↗