Unaffected first-degree relatives of essential tremor cases have more imbalance than age-matched control subjects

Endophenotypes are measurable clinical characteristics that may be present in individuals with increased risk for disease (e.g., unaffected family members). Endophenotypes are useful; they may clarify diagnosis in genetic studies and foster the development of animal models. In recent years, problems...

Full description

Saved in:
Bibliographic Details
Published in:Parkinsonism & related disorders 2018-07, Vol.52, p.24-29
Main Authors: Louis, Elan D., Meyers, James H., Cristal, Ashley D., Hickman, Ruby, Factor-Litvak, Pam
Format: Article
Language:English
Subjects:
Balance
Endophenotype
Epidemiology
Essential tremor
Gait
Genetics
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Endophenotypes are measurable clinical characteristics that may be present in individuals with increased risk for disease (e.g., unaffected family members). Endophenotypes are useful; they may clarify diagnosis in genetic studies and foster the development of animal models. In recent years, problems with balance and mild gait ataxia have been associated with essential tremor (ET). We compared gait and balance of first-degree relatives of ET cases (FD-ET) to that of age-matched controls (Co). One-hundred-ninety FD-ET and 68 Co, none of whom reported tremor or were diagnosed with ET, underwent a standardized assessment of gait and balance. FD-ET reported more near-falls in the past year (p = 0.015) and lower balance confidence according to the Activities of Balance Confidence (ABC-6) Scale (p = 0.03). The specific ABC-6 items for which FD-ET reported lower balance confidence than Co were being bumped into by people while walking (p = 0.006) and walking outside on icy sidewalks (p = 0.007). On videotaped neurological examination, FD-ET were able to stand in the tandem position for fewer seconds than were Co (p = 0.048). The differences between FD-ET and Co, although statistically significant, were clinically mild. FD-ET reported more near-falls in the past year and a reduction in balance confidence; additionally, ability to maintain tandem stance was impaired compared to Co. These data suggest a more pervasive abnormality of cerebellar dysfunction than previously conceived, extending beyond ET cases themselves and manifesting in mild form in their unaffected family members. •We studied gait and balance in unaffected first-degree relatives of ET cases.•Unaffected first-degree relatives of ET cases reported more near-falls than controls.•They also reported a reduction in balance confidence.•Their ability to maintain tandem stance was impaired compared to controls.•Mild cerebellar dysfunction extends beyond ET cases to their unaffected relatives.
ISSN:1353-8020
1873-5126
DOI:10.1016/j.parkreldis.2018.03.011