Objective: In this study, we describe the alcohol response in our familial essential tremor cohort by employing the Knudsen-Lorenz-Deuschl test for alcohol responsivity outside its original research group for the first time.

Background: Essential tremor (ET) is the most common movement disorder in adults and is considered to be a highly heritable disorder: the proportion of patients with a positive family history ranges from 20% to 90%. A reduction of the tremor amplitude after alcohol consumption is reported in approximately half of the patients and, therefore, alcohol sensitivity is supportive for essential tremor diagnosis.

Method: We recruited families with at least three trembling family members and reconfirmed all ET diagnoses. During the in-hospital alcohol responsivity test tremor was measured using Archimedes spirals at three time points: before alcohol consumption (T0), one hour after alcohol intake (T1), and the next morning (T2). Two raters independently scored these spirals according to the Bain-Findley spirography scale, the average of the two ratings was calculated as the Archimedes Spiral Rating (ASR) for each time point.

Results: Twenty-four participants (8 probands, 16 relatives), belonging to 9 families completed the study protocol. The ASR at T0 (3.5) and at T2 (4.0) were both significantly higher than the ASR at T1 (2.5) (both p<0.001). 18/24 participants had an initial ASR ≥ 3 at T0, permitting objective assessment of alcohol responsiveness with the Knudsen-Lorenz-Deuschl test. In 12/18 participants (67%), a difference in ASR between T0 and T1(dASR) ≥ 2 implies an improvement of tremor after consuming alcohol. 66,7% of the alcohol responders and 33,3% of the non-responders self-reported alcohol responsiveness before the test. There was no correlation between the dASR and self-assessment using the VAS-scale by participants. In only one family the three participating family members all showed a dASR ≥ 2, suggesting this is an alcohol-responding family.

Conclusion: Here, the first familial essential tremor cohort is presented where alcohol responsivity was objectively assessed. We confirmed that the Knudsen-Lorenz-Deuschl alcohol responsivity test is useful in determining objective alcohol responsivity, which, in this study, correlated weakly with subjective self-assessment. In the future, a larger population is needed to establish whether familial aggregation of alcohol responsivity occurs in essential tremor patients.

« Back to 2023 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/testing-for-alcohol-responsivity-in-familial-essential-tremor/