Ataxia in Essential Tremor: Describing the Differences Between Disease Process and Treatment Effect

Essential Tremor Clinical Trial

— ATAX  

Official title:

Ataxia in Essential Tremor: Describing the Differences Between Disease Process and Treatment Effect (ATAX)

Clinical Trial Details — Status: Terminated

Administrative data

• NCT number: NCT03769961
• Other study ID #: 18608
• Status: Terminated
• Start date: December 1, 2018
• Est. completion date: September 14, 2020

Study information

• Verified date: September 2020
• Source: Oregon Health and Science University
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The proposed study aims to characterize ataxia occurring in essential tremor and essential tremor with DBS.

Description:

Objectives: In recent years, there has been a growing amount of evidence tying Essential Tremor (ET) to cerebellar dysfunction. This has been clinically observed, demonstrated through specific gait measures of ataxia (often involving tandem gait), and confirmed through Positron emission tomography (PET) imaging. Deep Brain stimulation for ET has become a widely utilized therapeutic intervention for patients, and the bilateral thalamic ventralis intermedius (VIM) is most commonly implanted. However, it has been noted that in some patients gait ataxia significantly worsens post-op. This initially was thought to be a result of disease progression, but recent studies have in fact shown that this is a DBS related phenomenon.

Methods: Participants will have two visits to either the Portland VA or Oregon Health & Science University (OHSU). At each visit, several assessments of balance, tremor, gait and balance, and DBS settings will be made. The gait and balance assessments will be performed by a unblinded and a blinded rater.

Recruitment information / eligibility

• Status: Terminated
• Enrollment: 6
• Est. completion date: September 14, 2020
• Est. primary completion date: September 14, 2020
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 80 Years

Eligibility

Inclusion Criteria:

• Essential Tremor diagnosis at least 3 years duration

• Absence of other neurological signes (such as dystonia, ataxia, or Parkinsonism)

• Patients must be able to walk 2 minutes unassisted.

• Patients must be able to understand and consent to be in the study.

Exclusion Criteria:

• Patients who have had changes in DBS settings within the last 3 months.

• Patients who have had no initial improvement or response to DBS.

• ET medication changes in the last month.

• Actively abusing alcohol.

• A neurologic diagnosis other than ET that in the investigator's opinion could affect gait and/or balance.

• Atypical tremor disorder including by not limited to tremor due to multiple sclerosis, medication-induced tremor, Parkinson's disease, or parkinsonian syndrome.

• Dementia

Related Conditions & MeSH terms

• Ataxia
• Cerebellar Ataxia
• Cerebellar Diseases
• Deep Brain Stimulation
• Essential Tremor
• Tremor

Intervention

Other:
• No intervention
No interventions - Observational study

Locations

Country	Name	City	State
United States	Oregon Health & Science University	Portland	Oregon
United States	VA Portland Health Care System	Portland	Oregon

Sponsors (2)

Lead Sponsor	Collaborator
Oregon Health and Science University	Portland VA Medical Center

Country where clinical trial is conducted

United States, 

References & Publications (4)

Fasano A, Herzog J, Raethjen J, Rose FE, Muthuraman M, Volkmann J, Falk D, Elble R, Deuschl G. Gait ataxia in essential tremor is differentially modulated by thalamic stimulation. Brain. 2010 Dec;133(Pt 12):3635-48. doi: 10.1093/brain/awq267. Epub 2010 Oc — View Citation

Kronenbuerger M, Konczak J, Ziegler W, Buderath P, Frank B, Coenen VA, Kiening K, Reinacher P, Noth J, Timmann D. Balance and motor speech impairment in essential tremor. Cerebellum. 2009 Sep;8(3):389-98. doi: 10.1007/s12311-009-0111-y. Epub 2009 May 19. — View Citation

Nazzaro JM, Lyons KE, Pahwa R. Deep brain stimulation for essential tremor. Handb Clin Neurol. 2013;116:155-66. doi: 10.1016/B978-0-444-53497-2.00013-9. — View Citation

Ramirez-Zamora A, Boggs H, Pilitsis JG. Reduction in DBS frequency improves balance difficulties after thalamic DBS for essential tremor. J Neurol Sci. 2016 Aug 15;367:122-7. doi: 10.1016/j.jns.2016.06.001. Epub 2016 Jun 2. Review. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Ataxia Differences between DBS and no DBS	Compare the Scale of the Assessment and Rating of Ataxia (SARA) total score between DBS and no DBS participants with essential tremor. This 8-item scale rates gait (0-8 points), stance (0-6 points), sitting (0-4 points), speech disturbance (0-6 points), finger chase (0-4 points), nose-finger test (0-4 points), fast alternating hand movements (0-4 points), and heel-shin slide (0-4 points). Motor activists of the four extremities (items 5-8) assessments are performed bilaterally, mean values to obtain a total score. Cumulative score ranges from 0 (no ataxia) to 40 (most severe ataxia).	Visit 2 (after DBS has been turned off for 3-10 days)
Secondary	Balance Confidence	The Activities-Specific Balance Confidence Scale (ABC) is a subjective measure of confidence in performing various ambulatory activities without falling or experiencing a sense of unsteadiness. The ABC scale is a 16-item self-report measure in which participants rate their balance confidence on a 0-100 scale (0 = 0 no confidence, 100 = 100 complete confidence). Overall score is calculated by adding item scores and dividing by the total number of items.	Visit 2 (after DBS has been turned off for 3-10 days)